Research ArticleCentrifugation Storage and Filtration of OliveOil in an Oil Mill Effect on the Quality andContent of Minority Compounds

Alfonso M Vidal Sonia Alcala Antonia de Torres Manuel Moya and Francisco Espınola

Centre for Advanced Studies in Energy and Environment (CEAEMA) Agrifood Campus of International Excellence (ceiA3)Dept Chemical Environmental andMaterials Engineering University of Jaen Paraje Las Lagunillas Edif B-3 23071 Jaen Spain

Correspondence should be addressed to Alfonso M Vidal amvidalujaenes

Received 17 August 2018 Accepted 23 January 2019 Published 18 February 2019

Guest Editor Nabil Ben Youssef

Copyright copy 2019 AlfonsoM Vidal et alis is an open access article distributed under the Creative CommonsAttribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Centrifugation storage and ltration of olive oil were evaluated in an oil mill to determine their eect on the nal quality of virginolive oil e main functions of these processes are to clarify the olive oil by removing water solids and other possible suspendedparticles Although some changes were detected in the oil quality parameters after these processes all the samples were extra virginolive oil e phenolic and volatile compound content of the olive oil was inuenced by vertical centrifugation processingSignicantly vertical centrifugation led to a 53 reduction in ethanol content Oil storage before ltration resulted in a signicantincrease of around 30 in the peroxide index while the antioxidant capacity decreased by 78 Comparison of the results forltered and unltered oil samples revealed that the most signicant change was the reduction in the photosynthetic pigmentcontent with a decrease of around 50 in chlorophyll Due of all this the conditions applied in vertical centrifugation and thetime of storage of the olive oils should be further controlled enabling cleaning and decantation but avoiding the reduction of theantioxidant capacity and the content of phenolics compounds

1 Introduction

Virgin olive oil (VOO) is a fat known worldwide for itsbenecial properties for human health e consumption ofolive oil in the Mediterranean diet is associated with lowmortality from cardiovascular disease [1] Several healthbenets have been associated with certain antioxidantcompounds such as phenols [2] e health claims on ldquooliveoil polyphenolsrdquo by the EEC [3] refer to the impact ofbioactive phenolic compounds on the protection of bloodlipids against oxidative stress [4] High nutritional qualityarises from large amounts of unsaturated fatty acids in thecomposition of oil such as oleic acid and linolenic acid eproduction of VOO is solely carried out by physical andmechanical extraction processes Oil washing is a step of theprocess which is performed in a vertical centrifuge (VC)After obtaining the oil it is ltered to eliminate any solids inthe suspension

Washing represents an important source of oxidativereactions arising from the contact between water and oil [5]e distribution of phenolic compounds in the water and oilphases depends on their solubility in the phases [6] phenoliccompounds may thus be found in the wastewater andpomace Vertical centrifugation has a great eectiveness inclarifying the oil although this process reduces the con-centration of minor compounds in the extra virgin olive oil(EVOO) [7] e maximum oxygenation levels have beendetected after VC treatment e oxidation of olive oilduring its shelf-life is negatively aected by the concen-tration of dissolved oxygen [8]

Inert gases have been used for oil oxygenation pre-vention and found to signicantly extend the oil shelf-life[9] Other researchers have focused on the eect of the wateremployed in the VC and on the content of alkyl esters inolive oils [10] where the content of ethyl and methyl esterswere found to decrease with the use of water in the VC

HindawiJournal of Food QualityVolume 2019 Article ID 7381761 7 pageshttpsdoiorg10115520197381761

According to Gila et al [11] minimal water addition to theVC is the optimum option to improve the oil quality

-e content of certain compounds such as hydrox-ytyrosol tyrosol and the dialdehydic form of elenolic acidlinked to hydroxytyrosol underwent the most significantchanges [12] Other authors such as Masella et al [13] havedescribed slight variations in the concentrations of phenoliccompounds while comparing the composition of olive oilbefore and after the centrifugation process Generally adecrease in the content of these compounds is observed [14]that is by diffusion from the oil phase to the aqueous phaseMoreover the temperature of the added water was alsofound to influence the extraction process [15] Comparativetrials have also been performed on oil samples filtered usinga conventional filtration method instead of a VC [16]

-e turbidity of oil is caused by particles from planttissue in suspension and water droplets Such solids par-ticles and water can deteriorate the quality by promoting theoxidation and hydrolysis of olive oil [17] -e aim of fil-tration is eliminate these to increase oil shelf-life Severalchanges in the oil composition can occur during filtrationsuch as changes in the phenol and volatile compoundcontent or the color of the oil [18 19] Natural sedimentationis more favorable than filtration in delaying the oxidativedeterioration of oil nevertheless filtration provides a morestable sensory profile than do sedimentation and de-cantation [20]

Regarding filtration a laboratory-scale study has shownthat similar amounts of phenolic compounds are present infiltered and unfiltered EVOO [21] However another studythis time at pilot plant scale using filtration systems withinert gas flow (argon and nitrogen) and polypropylene filterbags showed that the content of most phenolic compoundsseemed to increase after filtration [22] Quantitative andqualitative changes especially on minor components weredetected which affected the EVOO quality [17] -e volatilecompound and sensory characteristics of EVOO can beinfluenced by oil filtration [23 24]

-e objective of this work was to determine the influenceof oil centrifugation storage and subsequent filtration onthe regulated quality parameters and the phenolic andvolatile compound contents of olive oil produced in a mill

2 Materials and Methods

21 RawMaterial Olive fruits (Olea europaea L) cv Picualwere harvested from irrigated land during the 2016ndash2017crop season in Mancha Real (Jaen Spain) and processedafter the harvest at a local olive oil mill A lot of approxi-mately 5000 kg of olives was used for the experimental trials-e maturity index (MI) or ripening degree was obtainedfollowing the method described by Espınola et al [25] -eSoxhlet method is used to analyse the oil content

22 Olive Oil Mill -e oil mill where the centrifugationstorage and filtration trials were carried out is located in theldquoCortijo Virgen de loss Milagrosrdquo Mancha Real (Spain) andhas a plant for the extraction of EVOO -e experiments

were performed with the mill working continuously-e VC(Pieralisi Jesi Italy) was operated at 6400 rpm-e optimumwater addition content was determined by the millworkersto be 5 Samples of oil pomace and paste were collected intriplicate at different times at approximately 20min in-tervals throughout the experiment -e extracted oil wasstored in a stainless-steel tank for 25 days -en the oil wasfiltered through a layer of hydrophilic cellulose acetate -efiltration was carried out continuously with an industrialfilter and three oil samples were collected at both the filterinlet and outlet All oil samples were stored in amber glassbottles filled with nitrogen and kept at minus18degC until furtheranalysis -e samples for the sensory analysis were sent to anexternal laboratory

23Analysis ofOliveOilQualityParameters -e free acidityperoxide index and extinction coefficients K232 and K270were determined according to the European Union standardmethod [26]

24 Analysis of Photosynthetic Pigments -e photosyntheticpigments composition was determined according to themethod of Mınguez-Mosquera et al [27] -e spectropho-tometer used was a Shimadzu (model UV-1800) -e ca-rotenoids and the chlorophylls were measured at awavelength of 470 nm and 670 nm respectively -e pig-ment concentration of the olive oils was expressed as mg ofpigment per kg of oil

25 Analysis of Volatile Compounds -e volatile com-pounds were quantified by following the method previouslydescribed by Vidal et al [28] -ey were analyzed byheadspace solid-phase microextraction (HS-SPME) and gaschromatography-flame ionization detection (GC-FID) -eSPME fiber is formed of CarboxenDVBpolydimethylsiloxaneand had 2 cm length and 5030 μm of film thickness It wasacquired from Supelco (Bellefonte PA USA) -e fiber hadbeen previously conditioned following the instructions ofthe manufacturer

GC-FID analysis was carried out on a gas chromato-graph model 7890B (Agilent Technologies CA USA) -ecapillary column used to the separation was a DB-WAXetr(Agilent Technologies USA) (30m of length 025 of mminternal diameter and 025 of μm coating) formed bypolyethylene glycol -e chromatographic peaks werequantified by the ldquoInternal Standardrdquo method -is methoduses internal and external standards A calibration curve wasmade with the relationship between the external and internalstandard (4-methyl-2-pentanol) -e purpose was to im-prove the quantification -e results are expressed as mg ofcompound per kg of olive oil

26 Analysis of Phenolic Compounds -e phenolic com-pounds present in the VOO were determined according tothe method of International Olive Council [29] A liquidchromatograph (Shimadzu Corp Kyoto Japan) was used-e column C18 BDS Hypersil (9ermo Scientific USA) was

2 Journal of Food Quality

employed in the chromatographic separation and its char-acteristics were 25 cm length 5 μm of particle size and46mm of internal diameter -e quantification was carriedout through the addition of syringic acid and tyrosol asinternal and external standard respectively -e analyticalstandards were used to identify the phenol compounds -eresults are showed as mg of tyrosol per kg of oil

27 Determination of the Antioxidant Potential -e anti-oxidant potential was determined according to the methoddescribed by Vidal et al [28] -e free radical 22-diphenyl-1-picrylhydrazyl (DPPH) was used to determine the anti-oxidant potential -e absorbance was measured at 515 nmof the sample and the DPPH solution Methanol was used assolvent and as the control -e absorbance obtained wasconverted into the DPPH concentration by interpolation ofthe calibration curve of absorbance versus DPPH concen-tration -e percentage of inhibition of DPPH radical wascalculated according to equation (1)

DPPHinhibition () [DPPH]0 minus[DPPH]sample

[DPPH]01113888 1113889 times 100

(1)

where [DPPH]0 and [DPPH]sample are the concentration ofthe control and sample respectively -e percentage ofinhibition DPPH was converted into the Trolox concen-tration using a calibration curve of the percentage of in-hibition versus the Trolox concentration -e antioxidantcapacity is expressed as micromol Trolox per kg of olive

28 SensoryAnalysis A panel formed by highly experiencedpeople carried out the quantitative descriptive sensoryanalysis of the EVOO -e method proposed by the In-ternational Olive Council described in the EEC Annex XII[26] was used -e determination was carried out in theAgri-food Laboratory of Granada (Granada Spain) -epositive attributes fruity bitter and pungent and thepossible presence of defects were determined

29 Statistical Analysis -e results were processed with theStatGraphics Centurion software version 17200 (Stat-point Technologies Inc Warrenton VA USA) -e meanvalues of the repeats and the Fisher significant least dif-ferences (Fisherrsquos LSD) for each response analyzed wasobtained

3 Results and Discussion

Olives were characterized by aMI of 174 and a content of oilof 2069 -is means that the skin of the olives had a greencolor with above less than 50 of purple -e percentage ofoil content is acceptable to extract considerable oil contentfor the early maturation stage at which the sample is found-e effects of vertical centrifugation storage and filtrationwere evaluated at industrial scale to obtain realistic resultsand thus be able to select the best parameters to produceEVOO Washing the oil in a VC resulted in some changes in

the quality parameters and composition Likewise somedifferences were observed between unfiltered and filteredsamples

31 Effect of Centrifugation on the EVOO Characteristics-e effect of oil centrifugation or washing was evaluated Forthis purpose the oil exiting the decanter and VC was an-alyzed -e results are provided in several tables qualityparameters and sensory characteristics (Table 1) volatilecompounds (Table 2) and phenolic compounds (Table 3)An analysis of the quality parameters was also conducted-e acidity was reduced by 202 after washing and theperoxide index increased by 99 -e K232 value experi-enced a slight drop of 42 after washing while K270 wasreduced by 79 -e photosynthetic pigment (chlorophyllsand carotenoids) content showed only a slight decrease aftervertical centrifugation of the olive oil -ese results aresimilar to those found in the literature [7] According to thequality parameters the olive oil category of every sampleremained EVOO as per the limits of the EEC [30] -e oliveoil category did not change after the washing process eventhough the quality parameters suffered some changes Fewvariations in the sensory characteristics were observed withjust a slight decrease in the bitterness and pungency after oilcentrifugation

-e results from the volatile compound analysis arepresented in Table 2 and are represented in Figure S1(A)After washing the total content of volatile compounds fromthe lipoxygenase (LOX) pathway experienced a reduction of90-ese results are consistent with those by Masella et al[13] All volatile compounds from the LOX pathway as wellas from other analyzed compounds exhibited a reduction intheir content after washing-is reduction is due to partitionphenomena between the oil and water phases [13] Of note isthe significant decrease of 533 in the ethanol contentwhich is produced by fermentation According to Alcalaet al [10] the use of water in the VC reduces the ethyl andmethyl ester content probably because some of the alcoholin the olive oil is extracted into water

-e phenolic compound content results are presentedin Table 3 and are represented in Figure S1(B) -e totalcontent of phenolic compounds mostly belonging to thegroup of secoiridoids decreased by 229 after washingthe oil Furthermore the antioxidant capacity decreasedby 270 during the oil washing process From an indi-vidual analysis of phenolic compounds hydroxytyrosolcinnamic acid and lignans did not undergo significantvariations during centrifugation In contrast tyrosolferulic acid p-coumaric acid vanillin secoiridoids andflavones had a decrease significant in their content duringcentrifugation -is reduction may be due to the transferof the hydrophilic phenols of the oil to the water and alsoto the increase of oxygen dissolved in the olive oil duringcentrifugation which can cause oxidation reactions on thephenolic compounds [6 13] -erefore the observeddecrease in the total content of this type of compounds inEVOO is due to the individual reduction in the amount ofeach compound

Journal of Food Quality 3

32 Effect of Storage of EVOO before Filtration Oil storagewas performed in a stainless-steel tank for 25days at roomtemperature A comparison was made between the oil samplesobtained on the day of oil elaboration and the samples collectedon the day of filtration to determine any changes in thecomposition which will in turn have an effect on the qualityparameters -e results are those compared between the col-umns called ldquocentrifuge exitbeginning of storagerdquo andldquounfilteredend of storagerdquo from Tables 1ndash3 -e most signif-icant changes were the increase in the peroxide index by 3166and an increase of 1496 for K232 similar to the results re-ported by Rodrigues et al [31] In contrast the other parametersdecreased after those 25days-emost significant changeswereobserved for the antioxidant capacity with a drop of 7771and a decrease of 5493 for the chlorophyll content and of4805 for the carotenoid content -ese results are similar tothose reported in the literature by Gutierrez and Fernandez[32] -e phenolic compound content decreased by 3353similar to the data reported by Gutierrez and Fernandez [32]and Kotsiou and Tasioula-Margari [33] A decrease in the

content of most phenolic compounds was also observed whichcould explain at least in part the loss of antioxidant capacity-is may be due to the loss of hydroxytyrosol and the decreaseof secoiridoid compounds since they are compounds with ahigh antioxidant capacity Making an individual analysis of thephenolic compounds during storage it is worth highlighting thetotal disappearance of hydroxytyrosol Furthermore thesecoiridoid compounds experiment a great decrease except p-HPEA-EA On the contrary tyrosol flavones and cinnamicacid have a slight increase in their content

In the sensory analysis only a slight decrease was ob-served similar to Gutierrez results [32]

33 Effect of Filtration on the EVOO Characteristics -eeffect of filtration on the characteristics of the olive oilsamples was evaluated For this purpose the characteristicsof filtered and unfiltered samples were compared -equality parameters sensory data and phenolic and volatilecompound content in the filtered and unfiltered oil samples are

Table 1 Quality parameters and sensory characteristics for the oil samples before and after vertical centrifugation storage and filtrationlowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredAcidity () 0186plusmn 0001a 0148plusmn 0001b 0122plusmn 0004c 0111plusmn 0002dPeroxide I (mEqmiddotO2kg) 307plusmn 007d 338plusmn 013c 445plusmn 003b 500plusmn 004aK232 133plusmn 008a 127plusmn 019a 146plusmn 003a 135plusmn 004aK270 013plusmn 001a 012plusmn 002ab 0106plusmn 0002bc 0096plusmn 0006cChlorophylls (mgkg) 3518plusmn 147a 3251plusmn 090a 2641plusmn 073b 1378plusmn 018cCarotenoids (mgkg) 1417plusmn 062a 1308plusmn 106ab 1224plusmn 032b 773plusmn 005cTotal HPLC phenols (mgkg) 43837plusmn 323a 33814plusmn 399b 22475plusmn 547c 22140plusmn 349cDPPH (micromolkg) 135983plusmn 1954a 99207plusmn 852b 22109plusmn 2156c 21371plusmn 1184cTotal LOX volatiles (mgkg) 982plusmn 026b 893plusmn 043b 1173plusmn 088a 1102plusmn 037aFruitiness 64plusmn 06a 60plusmn 03ab 58plusmn 01b 56plusmn 09bBitterness 35plusmn 03ab 36plusmn 03a 32plusmn 03bc 29plusmn 02cPungency 41plusmn 01a 43plusmn 02a 39plusmn 01ab 36plusmn 04blowastValues are expressed as meanplusmn SD (a b c d) indicate Fisherrsquos least significant differences (LSD) with statistically significant differences at 95 confidencelevel

Table 2 Individual content of volatile compounds before and after vertical centrifugation storage and filtration processes expressed inmgkglowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredLOX pathwayHexanal 042plusmn 001b 040plusmn 001b 056plusmn 002a 055plusmn 002aHexan-1-ol 038plusmn 002b 036plusmn 002b 064plusmn 006a 061plusmn 002a(E)-2-hexenal 325plusmn 003a 290plusmn 011b 327plusmn 022a 313plusmn 005ab(E)-2-hexen-1-ol 024plusmn 001b 023plusmn 002b 062plusmn 001a 065plusmn 002a(Z)-3-hexen-1-ol 180plusmn 004b 161plusmn 011b 233plusmn 021a 216plusmn 006a(Z)-3-hexenyl acetate 233plusmn 016b 225plusmn 010b 307plusmn 035a 244plusmn 008b1-penten-3-ol 028plusmn 000ab 023plusmn 003bc 021plusmn 0004c 032plusmn 007a1-penten-3-one 065plusmn 002c 056plusmn 004b 062plusmn 001b 071plusmn 002a(Z)-2-penten-1-ol 045plusmn 001a 039plusmn 004b 041plusmn 001ab 046plusmn 002a

Sugar fermentationEthanol 831plusmn 017a 388plusmn 009c 470plusmn 007c 627plusmn 018bAcetic acid 064plusmn 009b 053plusmn 007c 077plusmn 004a 055plusmn 001bc

Other compounds(E)-2-pentenal 028plusmn 001bc 025plusmn 003c 029plusmn 0004b 034plusmn 002aPentan-3-one 034plusmn 001b 031plusmn 002c 035plusmn 001b 041plusmn 001aNonanal 196plusmn 005c 175plusmn 012d 239plusmn 005b 263plusmn 012alowastValues are expressed as meanplusmn SD (a b c d) indicate Fisherrsquos least significant differences (LSD) with statistically significant differences at 95 confidencelevel

4 Journal of Food Quality

presented in Tables 1ndash3 After oil filtration slight but significantdifferences were observed-e acidity andK232 value decreasedslightly and the peroxide index increased by 122 In contrastthe photosynthetic pigment content was reduced during thefiltration process -e chlorophyll concentration decreased by478 in relation to the unfiltered oil and the carotenoidconcentration decreased by 368 -is means that the cel-lulose acetate filter collects a very important fraction of pho-tosynthetic pigments -ese results are consistent with thosereported by Gordillo et al [34] and Brkic Bubola et al [24]According to the quality parameters determined the olive oilcategory was still EVOO for all the samples as per the EEC [30]Although the quality parameters underwent some changes thecategory of the olive oil was not changed by the filtrationprocess-e antioxidant capacity was also similar in both cases

-e results of the volatile compounds are presented inTable 2 and are represented in Figure S2(A) -e volatilecompounds were analyzed separately to detect any differencesbetween the unfiltered and filtered samples Overall no majordifferences were observed between the two samples except forsome compounds (E)-2-Hexenal (Z)-3-hexenol and (Z)-3-hexenyl acetate were found in greater proportion in theunfiltered sample in contrast (Z)-2-pentenol 3-pentanoneand (E)-2-pentenal were detected in smaller proportion in theunfiltered sample -e amount of six-carbon-atom volatilecompounds decreased after filtration however the amount offive-carbon-atom volatile compounds increased after thefiltration process Although the observed differences areminor they still reveal a slight trend -ese results are similarto those previously reported in the literature by Bottino et al[23] and Brkic Bubola et al [24]

-e results obtained from the analysis of phenoliccompounds are shown in Table 3 and are represented inFigure S2(B) -e total amount of phenolic compounds wassimilar in both filtered and unfiltered samples Certain

similarities exist in both samples except for some particularcompounds Larger amounts of luteolin and p-coumaric acidwere detected in the unfiltered sample results similar tothose obtained by Bakhouche et al [19] that finds a re-duction of phenolic alcohols and flavones On the otherhand oleacin and 3 4-DHPEA-EA were found in smallerproportion in the unfiltered sample although they are notsignificant differences According to Gomez-Caravaca et al[35] the content of phenolic compounds slightly increasesafter the filtration process which may be due to the removalof water from the oil thus increasing the concentration ofdissolved substances in the oil

All other phenolic compounds presented no differencesin the filtered and unfiltered samples It should be noted thatthere are some investigations changing the filtering condi-tions such as that of Lozano-Sanchez et al [22] and findsome differences in the oils Also the type of filter used in thefiltration process can be affected the content of phenoliccompounds according to results obtained by Bakhoucheet al [19] and Gomez-Caravaca et al [35]

4 Conclusion

-e use of centrifugation storage (in order to decant) andfiltration in an industrial olive mill have the function of toclean and to clarify olive oils -e olive oil category was notchanged after the centrifugation storage and filtrationprocesses with slight changes in the fruitiness bitterness andpungency However centrifugation storage and filtrationproduced some significant changes found in the qualityparameters and minor composition

A relevant result was how the content of phenoliccompounds was affected by centrifugation A reduction inthe concentration of these compounds was observed afterthe vertical centrifugation process-is is probably the result

Table 3 Individual content of phenolic compounds before and after vertical centrifugation storage and filtration expressed in mgkglowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredPhenolic alcoholsHydroxytyrosol 624plusmn 010a 615plusmn 010a ndash ndashTyrosol 387plusmn 007a 234plusmn 015c 285plusmn 002b 288plusmn 003b

Phenolic acidsp-coumaric acid 304plusmn 015a 169plusmn 009c 274plusmn 001b 142plusmn 005dFerulic acid 736plusmn 016a 532plusmn 013b 077plusmn 003c 087plusmn 001cCinnamic acid 170plusmn 008a 164plusmn 005a 104plusmn 004b 088plusmn 029b

Secoiridoids34-DHPEA-EDA (oleacein) 14157plusmn 368a 9463plusmn 032b 2893plusmn 037c 2995plusmn 092c34-DHPEA-EA 10814plusmn 211a 8527plusmn 218b 2799plusmn 029c 2898plusmn 056cp-HPEA-EDA (oleocanthal) 7518plusmn 298a 6230plusmn 290b 3272plusmn 032c 3274plusmn 024cp-HPEA-EA 2198plusmn 238a 1780plusmn 149b 1845plusmn 017b 1861plusmn 037b

LignansPinoresinol + acetoxypinoresinol 1456plusmn 137a 1405plusmn 165a 1160plusmn 084b 1145plusmn 046b

FlavonesLuteolin 767plusmn 029b 750plusmn 048bc 975plusmn 056a 676plusmn 050cApigenin 524plusmn 048b 449plusmn 031c 737plusmn 013a 699plusmn 023a

OthersVainillin 185plusmn 003a 167plusmn 007b 152plusmn 004c 156plusmn 009clowastValues are expressed as meanplusmn SD (a b c d) indicate the Fisherrsquos least significant differences (LSD) with statistically significant differences at 95confidence level

Journal of Food Quality 5

of the transfer of hydrophilic phenols from the oil to thewater phase Centrifugation led to a 229 reduction in thetotal content of phenolic compounds Similarly the contentof volatile compounds from the LOX pathway exhibited adecrease after washing although the loss was just of 9 Itshould be noted that a significant decrease of 533 of theethanol compound content was observed after verticalcentrifugation of the olive oil

-e most relevant results from the oil samples stored for25 days before filtration were a significant increase in theperoxide index (around 30) and a 78 decrease in theantioxidant capacity A small number of differences weredetected after oil filtration with no differences in the sensorycharacteristics -e total amount of phenolic compoundsand volatile compounds from the LOX pathway was similarin both filtered and unfiltered samples furthermore theantioxidant capacity exhibited a similar trend to the phenoliccompound content On the contrary the photosyntheticpigment content decreased after the filtration process

From these results it is concluded that the water ad-dition in the vertical centrifugation and the time of storage ofolive oils should be reduced in order to avoid the decrease ofthe antioxidant capacity and phenolics compounds

Abbreviations

3 4-DHPEA-EA aldehyde and hydroxylic forms ofoleuropein aglycone

3 4-DHPEA-EDA(oleacein)

dialdehyde form of decarboxymethyloleuropein aglycone

DPPH 2 2-diphenyl-1-picrylhydrazylEVOO extra virgin olive oilLSD least significant differenceMI maturity indexMUFA monounsaturated fatty acidp-HPEA-EA aldehyde and hydroxylic forms of

ligstroside aglyconep-HPEA-EDA(oleocanthal)

dialdehyde form of decarboxymethylligstroside aglycone

VC vertical centrifugeVOO virgin olive oil

Data Availability

-e data used to support the findings of this study are in-cluded within the article

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-e authors are grateful to the Department of EconomyInnovation and Science of the Andalusian Regional Gov-ernment for the financial help provided through ResearchProject of Excellence PI11-AGR-7726 -e authors wouldalso like to acknowledge MONVA SL and all the staff atldquoCortijo Virgen de los Milagrosrdquo Mancha Real Jaen Spainfor their kindness and attention -e technical and human

support provided by CICT of Universidad de Jaen (UJAMINECO Junta de Andalucıa FEDER) is also gratefullyacknowledged

Supplementary Materials

Figure S1 Comparison of the volatile (A) and phenolic (B)compound content in oil before and after centrifugationData at the decanter exit and centrifuge exit -e error barsshow the standard deviation Figure S2 Comparison of thevolatile (A) and phenolic (B) compound content in un-filtered and filtered oil Data at the unfiltered and filteredoils -e error bars show the standard deviation (Supple-mentary Materials)

References

[1] M Covas ldquoOlive oil and the cardiovascular systemrdquo Phar-macological Research vol 55 no 3 pp 175ndash186 2007

[2] L Parkinson and S Cicerale ldquo-e health benefiting mecha-nisms of virgin olive oil phenolic compoundsrdquo Moleculesvol 21 no 12 p 1734 2016

[3] EEC European Commission Regulation 4322012 Establishinga List of Permitted Health Claims Made on Foods Other than9ose Referring to the Reduction of Disease Risk and toChildrenrsquos Development and Health Vol 136 EEC BrusselsBelgium 2012

[4] M Z Tsimidou and D Boskou ldquo-e health claim on ldquoolive oilpolyphenolsrdquo and the need for meaningful terminology andeffective analytical protocolsrdquo European Journal of LipidScience and Technology vol 117 no 8 pp 1091ndash1094 2015

[5] G Altieri F Genovese A Tauriello and G C Di RenzoldquoInnovative plant for the separation of high quality virginolive oil (VOO) at industrial scalerdquo Journal of Food Engi-neering vol 166 pp 325ndash334 2015

[6] P S Rodis V T Karathanos and A Mantzavinou ldquoParti-tioning of olive oil antioxidants between oil and water pha-sesrdquo Journal of Agricultural and Food Chemistry vol 50 no 3pp 596ndash601 2002

[7] L Guerrini O Luca Pantani and A Parenti ldquo-e impact ofvertical centrifugation on olive oil qualityrdquo Journal of FoodProcess Engineering vol 40 no 3 2017

[8] A Parenti P Spugnoli P Masella and L Calamai ldquoInfluenceof the extraction process on dissolved oxygen in olive oilrdquoEuropean Journal of Lipid Science and Technology vol 109no 12 pp 1180ndash1185 2007

[9] P Masella A Parenti P Spugnoli and L Calamai ldquoVerticalcentrifugation of virgin olive oil under inert gasrdquo EuropeanJournal of Lipid Science and Technology vol 114 no 9pp 1094ndash1096 2012

[10] S Alcala M T Ocantildea J R Cardenas et al ldquoAlkyl esterscontent and other quality parameters in oil mill a responsesurface methodology studyrdquo European Journal of Lipid Sci-ence and Technology vol 119 no 1 article 1600026 2017

[11] A Gila G Beltran M A Bejaoui M P Aguilera andA Jimenez ldquoHow clarification systems can affect virgin oliveoil composition and quality at industrial scalerdquo EuropeanJournal of Lipid Science and Technology vol 119 no 10 article1600479 2017

[12] J M Garcıa K Yousfi R Mateos M Olmo and A CertldquoReduction of oil bitterness by heating of olive (Olea euro-paea) fruitsrdquo Journal of Agricultural and Food Chemistryvol 49 no 9 pp 4231ndash4235 2001

6 Journal of Food Quality

employed in the chromatographic separation and its char-acteristics were 25 cm length 5 μm of particle size and46mm of internal diameter -e quantification was carriedout through the addition of syringic acid and tyrosol asinternal and external standard respectively -e analyticalstandards were used to identify the phenol compounds -eresults are showed as mg of tyrosol per kg of oil

27 Determination of the Antioxidant Potential -e anti-oxidant potential was determined according to the methoddescribed by Vidal et al [28] -e free radical 22-diphenyl-1-picrylhydrazyl (DPPH) was used to determine the anti-oxidant potential -e absorbance was measured at 515 nmof the sample and the DPPH solution Methanol was used assolvent and as the control -e absorbance obtained wasconverted into the DPPH concentration by interpolation ofthe calibration curve of absorbance versus DPPH concen-tration -e percentage of inhibition of DPPH radical wascalculated according to equation (1)

DPPHinhibition () [DPPH]0 minus[DPPH]sample

[DPPH]01113888 1113889 times 100

(1)

where [DPPH]0 and [DPPH]sample are the concentration ofthe control and sample respectively -e percentage ofinhibition DPPH was converted into the Trolox concen-tration using a calibration curve of the percentage of in-hibition versus the Trolox concentration -e antioxidantcapacity is expressed as micromol Trolox per kg of olive

28 SensoryAnalysis A panel formed by highly experiencedpeople carried out the quantitative descriptive sensoryanalysis of the EVOO -e method proposed by the In-ternational Olive Council described in the EEC Annex XII[26] was used -e determination was carried out in theAgri-food Laboratory of Granada (Granada Spain) -epositive attributes fruity bitter and pungent and thepossible presence of defects were determined

29 Statistical Analysis -e results were processed with theStatGraphics Centurion software version 17200 (Stat-point Technologies Inc Warrenton VA USA) -e meanvalues of the repeats and the Fisher significant least dif-ferences (Fisherrsquos LSD) for each response analyzed wasobtained

3 Results and Discussion

Olives were characterized by aMI of 174 and a content of oilof 2069 -is means that the skin of the olives had a greencolor with above less than 50 of purple -e percentage ofoil content is acceptable to extract considerable oil contentfor the early maturation stage at which the sample is found-e effects of vertical centrifugation storage and filtrationwere evaluated at industrial scale to obtain realistic resultsand thus be able to select the best parameters to produceEVOO Washing the oil in a VC resulted in some changes in

the quality parameters and composition Likewise somedifferences were observed between unfiltered and filteredsamples

31 Effect of Centrifugation on the EVOO Characteristics-e effect of oil centrifugation or washing was evaluated Forthis purpose the oil exiting the decanter and VC was an-alyzed -e results are provided in several tables qualityparameters and sensory characteristics (Table 1) volatilecompounds (Table 2) and phenolic compounds (Table 3)An analysis of the quality parameters was also conducted-e acidity was reduced by 202 after washing and theperoxide index increased by 99 -e K232 value experi-enced a slight drop of 42 after washing while K270 wasreduced by 79 -e photosynthetic pigment (chlorophyllsand carotenoids) content showed only a slight decrease aftervertical centrifugation of the olive oil -ese results aresimilar to those found in the literature [7] According to thequality parameters the olive oil category of every sampleremained EVOO as per the limits of the EEC [30] -e oliveoil category did not change after the washing process eventhough the quality parameters suffered some changes Fewvariations in the sensory characteristics were observed withjust a slight decrease in the bitterness and pungency after oilcentrifugation

-e results from the volatile compound analysis arepresented in Table 2 and are represented in Figure S1(A)After washing the total content of volatile compounds fromthe lipoxygenase (LOX) pathway experienced a reduction of90-ese results are consistent with those by Masella et al[13] All volatile compounds from the LOX pathway as wellas from other analyzed compounds exhibited a reduction intheir content after washing-is reduction is due to partitionphenomena between the oil and water phases [13] Of note isthe significant decrease of 533 in the ethanol contentwhich is produced by fermentation According to Alcalaet al [10] the use of water in the VC reduces the ethyl andmethyl ester content probably because some of the alcoholin the olive oil is extracted into water

-e phenolic compound content results are presentedin Table 3 and are represented in Figure S1(B) -e totalcontent of phenolic compounds mostly belonging to thegroup of secoiridoids decreased by 229 after washingthe oil Furthermore the antioxidant capacity decreasedby 270 during the oil washing process From an indi-vidual analysis of phenolic compounds hydroxytyrosolcinnamic acid and lignans did not undergo significantvariations during centrifugation In contrast tyrosolferulic acid p-coumaric acid vanillin secoiridoids andflavones had a decrease significant in their content duringcentrifugation -is reduction may be due to the transferof the hydrophilic phenols of the oil to the water and alsoto the increase of oxygen dissolved in the olive oil duringcentrifugation which can cause oxidation reactions on thephenolic compounds [6 13] -erefore the observeddecrease in the total content of this type of compounds inEVOO is due to the individual reduction in the amount ofeach compound

Journal of Food Quality 3

32 Effect of Storage of EVOO before Filtration Oil storagewas performed in a stainless-steel tank for 25days at roomtemperature A comparison was made between the oil samplesobtained on the day of oil elaboration and the samples collectedon the day of filtration to determine any changes in thecomposition which will in turn have an effect on the qualityparameters -e results are those compared between the col-umns called ldquocentrifuge exitbeginning of storagerdquo andldquounfilteredend of storagerdquo from Tables 1ndash3 -e most signif-icant changes were the increase in the peroxide index by 3166and an increase of 1496 for K232 similar to the results re-ported by Rodrigues et al [31] In contrast the other parametersdecreased after those 25days-emost significant changeswereobserved for the antioxidant capacity with a drop of 7771and a decrease of 5493 for the chlorophyll content and of4805 for the carotenoid content -ese results are similar tothose reported in the literature by Gutierrez and Fernandez[32] -e phenolic compound content decreased by 3353similar to the data reported by Gutierrez and Fernandez [32]and Kotsiou and Tasioula-Margari [33] A decrease in the

content of most phenolic compounds was also observed whichcould explain at least in part the loss of antioxidant capacity-is may be due to the loss of hydroxytyrosol and the decreaseof secoiridoid compounds since they are compounds with ahigh antioxidant capacity Making an individual analysis of thephenolic compounds during storage it is worth highlighting thetotal disappearance of hydroxytyrosol Furthermore thesecoiridoid compounds experiment a great decrease except p-HPEA-EA On the contrary tyrosol flavones and cinnamicacid have a slight increase in their content

In the sensory analysis only a slight decrease was ob-served similar to Gutierrez results [32]

33 Effect of Filtration on the EVOO Characteristics -eeffect of filtration on the characteristics of the olive oilsamples was evaluated For this purpose the characteristicsof filtered and unfiltered samples were compared -equality parameters sensory data and phenolic and volatilecompound content in the filtered and unfiltered oil samples are

Table 1 Quality parameters and sensory characteristics for the oil samples before and after vertical centrifugation storage and filtrationlowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredAcidity () 0186plusmn 0001a 0148plusmn 0001b 0122plusmn 0004c 0111plusmn 0002dPeroxide I (mEqmiddotO2kg) 307plusmn 007d 338plusmn 013c 445plusmn 003b 500plusmn 004aK232 133plusmn 008a 127plusmn 019a 146plusmn 003a 135plusmn 004aK270 013plusmn 001a 012plusmn 002ab 0106plusmn 0002bc 0096plusmn 0006cChlorophylls (mgkg) 3518plusmn 147a 3251plusmn 090a 2641plusmn 073b 1378plusmn 018cCarotenoids (mgkg) 1417plusmn 062a 1308plusmn 106ab 1224plusmn 032b 773plusmn 005cTotal HPLC phenols (mgkg) 43837plusmn 323a 33814plusmn 399b 22475plusmn 547c 22140plusmn 349cDPPH (micromolkg) 135983plusmn 1954a 99207plusmn 852b 22109plusmn 2156c 21371plusmn 1184cTotal LOX volatiles (mgkg) 982plusmn 026b 893plusmn 043b 1173plusmn 088a 1102plusmn 037aFruitiness 64plusmn 06a 60plusmn 03ab 58plusmn 01b 56plusmn 09bBitterness 35plusmn 03ab 36plusmn 03a 32plusmn 03bc 29plusmn 02cPungency 41plusmn 01a 43plusmn 02a 39plusmn 01ab 36plusmn 04blowastValues are expressed as meanplusmn SD (a b c d) indicate Fisherrsquos least significant differences (LSD) with statistically significant differences at 95 confidencelevel

Table 2 Individual content of volatile compounds before and after vertical centrifugation storage and filtration processes expressed inmgkglowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredLOX pathwayHexanal 042plusmn 001b 040plusmn 001b 056plusmn 002a 055plusmn 002aHexan-1-ol 038plusmn 002b 036plusmn 002b 064plusmn 006a 061plusmn 002a(E)-2-hexenal 325plusmn 003a 290plusmn 011b 327plusmn 022a 313plusmn 005ab(E)-2-hexen-1-ol 024plusmn 001b 023plusmn 002b 062plusmn 001a 065plusmn 002a(Z)-3-hexen-1-ol 180plusmn 004b 161plusmn 011b 233plusmn 021a 216plusmn 006a(Z)-3-hexenyl acetate 233plusmn 016b 225plusmn 010b 307plusmn 035a 244plusmn 008b1-penten-3-ol 028plusmn 000ab 023plusmn 003bc 021plusmn 0004c 032plusmn 007a1-penten-3-one 065plusmn 002c 056plusmn 004b 062plusmn 001b 071plusmn 002a(Z)-2-penten-1-ol 045plusmn 001a 039plusmn 004b 041plusmn 001ab 046plusmn 002a

Sugar fermentationEthanol 831plusmn 017a 388plusmn 009c 470plusmn 007c 627plusmn 018bAcetic acid 064plusmn 009b 053plusmn 007c 077plusmn 004a 055plusmn 001bc

Other compounds(E)-2-pentenal 028plusmn 001bc 025plusmn 003c 029plusmn 0004b 034plusmn 002aPentan-3-one 034plusmn 001b 031plusmn 002c 035plusmn 001b 041plusmn 001aNonanal 196plusmn 005c 175plusmn 012d 239plusmn 005b 263plusmn 012alowastValues are expressed as meanplusmn SD (a b c d) indicate Fisherrsquos least significant differences (LSD) with statistically significant differences at 95 confidencelevel

4 Journal of Food Quality

presented in Tables 1ndash3 After oil filtration slight but significantdifferences were observed-e acidity andK232 value decreasedslightly and the peroxide index increased by 122 In contrastthe photosynthetic pigment content was reduced during thefiltration process -e chlorophyll concentration decreased by478 in relation to the unfiltered oil and the carotenoidconcentration decreased by 368 -is means that the cel-lulose acetate filter collects a very important fraction of pho-tosynthetic pigments -ese results are consistent with thosereported by Gordillo et al [34] and Brkic Bubola et al [24]According to the quality parameters determined the olive oilcategory was still EVOO for all the samples as per the EEC [30]Although the quality parameters underwent some changes thecategory of the olive oil was not changed by the filtrationprocess-e antioxidant capacity was also similar in both cases

-e results of the volatile compounds are presented inTable 2 and are represented in Figure S2(A) -e volatilecompounds were analyzed separately to detect any differencesbetween the unfiltered and filtered samples Overall no majordifferences were observed between the two samples except forsome compounds (E)-2-Hexenal (Z)-3-hexenol and (Z)-3-hexenyl acetate were found in greater proportion in theunfiltered sample in contrast (Z)-2-pentenol 3-pentanoneand (E)-2-pentenal were detected in smaller proportion in theunfiltered sample -e amount of six-carbon-atom volatilecompounds decreased after filtration however the amount offive-carbon-atom volatile compounds increased after thefiltration process Although the observed differences areminor they still reveal a slight trend -ese results are similarto those previously reported in the literature by Bottino et al[23] and Brkic Bubola et al [24]

-e results obtained from the analysis of phenoliccompounds are shown in Table 3 and are represented inFigure S2(B) -e total amount of phenolic compounds wassimilar in both filtered and unfiltered samples Certain

similarities exist in both samples except for some particularcompounds Larger amounts of luteolin and p-coumaric acidwere detected in the unfiltered sample results similar tothose obtained by Bakhouche et al [19] that finds a re-duction of phenolic alcohols and flavones On the otherhand oleacin and 3 4-DHPEA-EA were found in smallerproportion in the unfiltered sample although they are notsignificant differences According to Gomez-Caravaca et al[35] the content of phenolic compounds slightly increasesafter the filtration process which may be due to the removalof water from the oil thus increasing the concentration ofdissolved substances in the oil

All other phenolic compounds presented no differencesin the filtered and unfiltered samples It should be noted thatthere are some investigations changing the filtering condi-tions such as that of Lozano-Sanchez et al [22] and findsome differences in the oils Also the type of filter used in thefiltration process can be affected the content of phenoliccompounds according to results obtained by Bakhoucheet al [19] and Gomez-Caravaca et al [35]

4 Conclusion

-e use of centrifugation storage (in order to decant) andfiltration in an industrial olive mill have the function of toclean and to clarify olive oils -e olive oil category was notchanged after the centrifugation storage and filtrationprocesses with slight changes in the fruitiness bitterness andpungency However centrifugation storage and filtrationproduced some significant changes found in the qualityparameters and minor composition

A relevant result was how the content of phenoliccompounds was affected by centrifugation A reduction inthe concentration of these compounds was observed afterthe vertical centrifugation process-is is probably the result

Table 3 Individual content of phenolic compounds before and after vertical centrifugation storage and filtration expressed in mgkglowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredPhenolic alcoholsHydroxytyrosol 624plusmn 010a 615plusmn 010a ndash ndashTyrosol 387plusmn 007a 234plusmn 015c 285plusmn 002b 288plusmn 003b

Phenolic acidsp-coumaric acid 304plusmn 015a 169plusmn 009c 274plusmn 001b 142plusmn 005dFerulic acid 736plusmn 016a 532plusmn 013b 077plusmn 003c 087plusmn 001cCinnamic acid 170plusmn 008a 164plusmn 005a 104plusmn 004b 088plusmn 029b

Secoiridoids34-DHPEA-EDA (oleacein) 14157plusmn 368a 9463plusmn 032b 2893plusmn 037c 2995plusmn 092c34-DHPEA-EA 10814plusmn 211a 8527plusmn 218b 2799plusmn 029c 2898plusmn 056cp-HPEA-EDA (oleocanthal) 7518plusmn 298a 6230plusmn 290b 3272plusmn 032c 3274plusmn 024cp-HPEA-EA 2198plusmn 238a 1780plusmn 149b 1845plusmn 017b 1861plusmn 037b

LignansPinoresinol + acetoxypinoresinol 1456plusmn 137a 1405plusmn 165a 1160plusmn 084b 1145plusmn 046b

FlavonesLuteolin 767plusmn 029b 750plusmn 048bc 975plusmn 056a 676plusmn 050cApigenin 524plusmn 048b 449plusmn 031c 737plusmn 013a 699plusmn 023a

OthersVainillin 185plusmn 003a 167plusmn 007b 152plusmn 004c 156plusmn 009clowastValues are expressed as meanplusmn SD (a b c d) indicate the Fisherrsquos least significant differences (LSD) with statistically significant differences at 95confidence level

Journal of Food Quality 5

of the transfer of hydrophilic phenols from the oil to thewater phase Centrifugation led to a 229 reduction in thetotal content of phenolic compounds Similarly the contentof volatile compounds from the LOX pathway exhibited adecrease after washing although the loss was just of 9 Itshould be noted that a significant decrease of 533 of theethanol compound content was observed after verticalcentrifugation of the olive oil

-e most relevant results from the oil samples stored for25 days before filtration were a significant increase in theperoxide index (around 30) and a 78 decrease in theantioxidant capacity A small number of differences weredetected after oil filtration with no differences in the sensorycharacteristics -e total amount of phenolic compoundsand volatile compounds from the LOX pathway was similarin both filtered and unfiltered samples furthermore theantioxidant capacity exhibited a similar trend to the phenoliccompound content On the contrary the photosyntheticpigment content decreased after the filtration process

From these results it is concluded that the water ad-dition in the vertical centrifugation and the time of storage ofolive oils should be reduced in order to avoid the decrease ofthe antioxidant capacity and phenolics compounds

Abbreviations

3 4-DHPEA-EA aldehyde and hydroxylic forms ofoleuropein aglycone

3 4-DHPEA-EDA(oleacein)

dialdehyde form of decarboxymethyloleuropein aglycone

DPPH 2 2-diphenyl-1-picrylhydrazylEVOO extra virgin olive oilLSD least significant differenceMI maturity indexMUFA monounsaturated fatty acidp-HPEA-EA aldehyde and hydroxylic forms of

ligstroside aglyconep-HPEA-EDA(oleocanthal)

dialdehyde form of decarboxymethylligstroside aglycone

VC vertical centrifugeVOO virgin olive oil

Data Availability

-e data used to support the findings of this study are in-cluded within the article

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-e authors are grateful to the Department of EconomyInnovation and Science of the Andalusian Regional Gov-ernment for the financial help provided through ResearchProject of Excellence PI11-AGR-7726 -e authors wouldalso like to acknowledge MONVA SL and all the staff atldquoCortijo Virgen de los Milagrosrdquo Mancha Real Jaen Spainfor their kindness and attention -e technical and human

support provided by CICT of Universidad de Jaen (UJAMINECO Junta de Andalucıa FEDER) is also gratefullyacknowledged

Supplementary Materials

Figure S1 Comparison of the volatile (A) and phenolic (B)compound content in oil before and after centrifugationData at the decanter exit and centrifuge exit -e error barsshow the standard deviation Figure S2 Comparison of thevolatile (A) and phenolic (B) compound content in un-filtered and filtered oil Data at the unfiltered and filteredoils -e error bars show the standard deviation (Supple-mentary Materials)

References

[1] M Covas ldquoOlive oil and the cardiovascular systemrdquo Phar-macological Research vol 55 no 3 pp 175ndash186 2007

[2] L Parkinson and S Cicerale ldquo-e health benefiting mecha-nisms of virgin olive oil phenolic compoundsrdquo Moleculesvol 21 no 12 p 1734 2016

[3] EEC European Commission Regulation 4322012 Establishinga List of Permitted Health Claims Made on Foods Other than9ose Referring to the Reduction of Disease Risk and toChildrenrsquos Development and Health Vol 136 EEC BrusselsBelgium 2012

[4] M Z Tsimidou and D Boskou ldquo-e health claim on ldquoolive oilpolyphenolsrdquo and the need for meaningful terminology andeffective analytical protocolsrdquo European Journal of LipidScience and Technology vol 117 no 8 pp 1091ndash1094 2015

[5] G Altieri F Genovese A Tauriello and G C Di RenzoldquoInnovative plant for the separation of high quality virginolive oil (VOO) at industrial scalerdquo Journal of Food Engi-neering vol 166 pp 325ndash334 2015

[6] P S Rodis V T Karathanos and A Mantzavinou ldquoParti-tioning of olive oil antioxidants between oil and water pha-sesrdquo Journal of Agricultural and Food Chemistry vol 50 no 3pp 596ndash601 2002

[7] L Guerrini O Luca Pantani and A Parenti ldquo-e impact ofvertical centrifugation on olive oil qualityrdquo Journal of FoodProcess Engineering vol 40 no 3 2017

[8] A Parenti P Spugnoli P Masella and L Calamai ldquoInfluenceof the extraction process on dissolved oxygen in olive oilrdquoEuropean Journal of Lipid Science and Technology vol 109no 12 pp 1180ndash1185 2007

[9] P Masella A Parenti P Spugnoli and L Calamai ldquoVerticalcentrifugation of virgin olive oil under inert gasrdquo EuropeanJournal of Lipid Science and Technology vol 114 no 9pp 1094ndash1096 2012

[10] S Alcala M T Ocantildea J R Cardenas et al ldquoAlkyl esterscontent and other quality parameters in oil mill a responsesurface methodology studyrdquo European Journal of Lipid Sci-ence and Technology vol 119 no 1 article 1600026 2017

[11] A Gila G Beltran M A Bejaoui M P Aguilera andA Jimenez ldquoHow clarification systems can affect virgin oliveoil composition and quality at industrial scalerdquo EuropeanJournal of Lipid Science and Technology vol 119 no 10 article1600479 2017

[12] J M Garcıa K Yousfi R Mateos M Olmo and A CertldquoReduction of oil bitterness by heating of olive (Olea euro-paea) fruitsrdquo Journal of Agricultural and Food Chemistryvol 49 no 9 pp 4231ndash4235 2001

6 Journal of Food Quality

32 Effect of Storage of EVOO before Filtration Oil storagewas performed in a stainless-steel tank for 25days at roomtemperature A comparison was made between the oil samplesobtained on the day of oil elaboration and the samples collectedon the day of filtration to determine any changes in thecomposition which will in turn have an effect on the qualityparameters -e results are those compared between the col-umns called ldquocentrifuge exitbeginning of storagerdquo andldquounfilteredend of storagerdquo from Tables 1ndash3 -e most signif-icant changes were the increase in the peroxide index by 3166and an increase of 1496 for K232 similar to the results re-ported by Rodrigues et al [31] In contrast the other parametersdecreased after those 25days-emost significant changeswereobserved for the antioxidant capacity with a drop of 7771and a decrease of 5493 for the chlorophyll content and of4805 for the carotenoid content -ese results are similar tothose reported in the literature by Gutierrez and Fernandez[32] -e phenolic compound content decreased by 3353similar to the data reported by Gutierrez and Fernandez [32]and Kotsiou and Tasioula-Margari [33] A decrease in the

content of most phenolic compounds was also observed whichcould explain at least in part the loss of antioxidant capacity-is may be due to the loss of hydroxytyrosol and the decreaseof secoiridoid compounds since they are compounds with ahigh antioxidant capacity Making an individual analysis of thephenolic compounds during storage it is worth highlighting thetotal disappearance of hydroxytyrosol Furthermore thesecoiridoid compounds experiment a great decrease except p-HPEA-EA On the contrary tyrosol flavones and cinnamicacid have a slight increase in their content

In the sensory analysis only a slight decrease was ob-served similar to Gutierrez results [32]

33 Effect of Filtration on the EVOO Characteristics -eeffect of filtration on the characteristics of the olive oilsamples was evaluated For this purpose the characteristicsof filtered and unfiltered samples were compared -equality parameters sensory data and phenolic and volatilecompound content in the filtered and unfiltered oil samples are

Table 1 Quality parameters and sensory characteristics for the oil samples before and after vertical centrifugation storage and filtrationlowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredAcidity () 0186plusmn 0001a 0148plusmn 0001b 0122plusmn 0004c 0111plusmn 0002dPeroxide I (mEqmiddotO2kg) 307plusmn 007d 338plusmn 013c 445plusmn 003b 500plusmn 004aK232 133plusmn 008a 127plusmn 019a 146plusmn 003a 135plusmn 004aK270 013plusmn 001a 012plusmn 002ab 0106plusmn 0002bc 0096plusmn 0006cChlorophylls (mgkg) 3518plusmn 147a 3251plusmn 090a 2641plusmn 073b 1378plusmn 018cCarotenoids (mgkg) 1417plusmn 062a 1308plusmn 106ab 1224plusmn 032b 773plusmn 005cTotal HPLC phenols (mgkg) 43837plusmn 323a 33814plusmn 399b 22475plusmn 547c 22140plusmn 349cDPPH (micromolkg) 135983plusmn 1954a 99207plusmn 852b 22109plusmn 2156c 21371plusmn 1184cTotal LOX volatiles (mgkg) 982plusmn 026b 893plusmn 043b 1173plusmn 088a 1102plusmn 037aFruitiness 64plusmn 06a 60plusmn 03ab 58plusmn 01b 56plusmn 09bBitterness 35plusmn 03ab 36plusmn 03a 32plusmn 03bc 29plusmn 02cPungency 41plusmn 01a 43plusmn 02a 39plusmn 01ab 36plusmn 04blowastValues are expressed as meanplusmn SD (a b c d) indicate Fisherrsquos least significant differences (LSD) with statistically significant differences at 95 confidencelevel

Table 2 Individual content of volatile compounds before and after vertical centrifugation storage and filtration processes expressed inmgkglowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredLOX pathwayHexanal 042plusmn 001b 040plusmn 001b 056plusmn 002a 055plusmn 002aHexan-1-ol 038plusmn 002b 036plusmn 002b 064plusmn 006a 061plusmn 002a(E)-2-hexenal 325plusmn 003a 290plusmn 011b 327plusmn 022a 313plusmn 005ab(E)-2-hexen-1-ol 024plusmn 001b 023plusmn 002b 062plusmn 001a 065plusmn 002a(Z)-3-hexen-1-ol 180plusmn 004b 161plusmn 011b 233plusmn 021a 216plusmn 006a(Z)-3-hexenyl acetate 233plusmn 016b 225plusmn 010b 307plusmn 035a 244plusmn 008b1-penten-3-ol 028plusmn 000ab 023plusmn 003bc 021plusmn 0004c 032plusmn 007a1-penten-3-one 065plusmn 002c 056plusmn 004b 062plusmn 001b 071plusmn 002a(Z)-2-penten-1-ol 045plusmn 001a 039plusmn 004b 041plusmn 001ab 046plusmn 002a

Sugar fermentationEthanol 831plusmn 017a 388plusmn 009c 470plusmn 007c 627plusmn 018bAcetic acid 064plusmn 009b 053plusmn 007c 077plusmn 004a 055plusmn 001bc

Other compounds(E)-2-pentenal 028plusmn 001bc 025plusmn 003c 029plusmn 0004b 034plusmn 002aPentan-3-one 034plusmn 001b 031plusmn 002c 035plusmn 001b 041plusmn 001aNonanal 196plusmn 005c 175plusmn 012d 239plusmn 005b 263plusmn 012alowastValues are expressed as meanplusmn SD (a b c d) indicate Fisherrsquos least significant differences (LSD) with statistically significant differences at 95 confidencelevel

4 Journal of Food Quality

presented in Tables 1ndash3 After oil filtration slight but significantdifferences were observed-e acidity andK232 value decreasedslightly and the peroxide index increased by 122 In contrastthe photosynthetic pigment content was reduced during thefiltration process -e chlorophyll concentration decreased by478 in relation to the unfiltered oil and the carotenoidconcentration decreased by 368 -is means that the cel-lulose acetate filter collects a very important fraction of pho-tosynthetic pigments -ese results are consistent with thosereported by Gordillo et al [34] and Brkic Bubola et al [24]According to the quality parameters determined the olive oilcategory was still EVOO for all the samples as per the EEC [30]Although the quality parameters underwent some changes thecategory of the olive oil was not changed by the filtrationprocess-e antioxidant capacity was also similar in both cases

-e results of the volatile compounds are presented inTable 2 and are represented in Figure S2(A) -e volatilecompounds were analyzed separately to detect any differencesbetween the unfiltered and filtered samples Overall no majordifferences were observed between the two samples except forsome compounds (E)-2-Hexenal (Z)-3-hexenol and (Z)-3-hexenyl acetate were found in greater proportion in theunfiltered sample in contrast (Z)-2-pentenol 3-pentanoneand (E)-2-pentenal were detected in smaller proportion in theunfiltered sample -e amount of six-carbon-atom volatilecompounds decreased after filtration however the amount offive-carbon-atom volatile compounds increased after thefiltration process Although the observed differences areminor they still reveal a slight trend -ese results are similarto those previously reported in the literature by Bottino et al[23] and Brkic Bubola et al [24]

-e results obtained from the analysis of phenoliccompounds are shown in Table 3 and are represented inFigure S2(B) -e total amount of phenolic compounds wassimilar in both filtered and unfiltered samples Certain

similarities exist in both samples except for some particularcompounds Larger amounts of luteolin and p-coumaric acidwere detected in the unfiltered sample results similar tothose obtained by Bakhouche et al [19] that finds a re-duction of phenolic alcohols and flavones On the otherhand oleacin and 3 4-DHPEA-EA were found in smallerproportion in the unfiltered sample although they are notsignificant differences According to Gomez-Caravaca et al[35] the content of phenolic compounds slightly increasesafter the filtration process which may be due to the removalof water from the oil thus increasing the concentration ofdissolved substances in the oil

All other phenolic compounds presented no differencesin the filtered and unfiltered samples It should be noted thatthere are some investigations changing the filtering condi-tions such as that of Lozano-Sanchez et al [22] and findsome differences in the oils Also the type of filter used in thefiltration process can be affected the content of phenoliccompounds according to results obtained by Bakhoucheet al [19] and Gomez-Caravaca et al [35]

4 Conclusion

-e use of centrifugation storage (in order to decant) andfiltration in an industrial olive mill have the function of toclean and to clarify olive oils -e olive oil category was notchanged after the centrifugation storage and filtrationprocesses with slight changes in the fruitiness bitterness andpungency However centrifugation storage and filtrationproduced some significant changes found in the qualityparameters and minor composition

A relevant result was how the content of phenoliccompounds was affected by centrifugation A reduction inthe concentration of these compounds was observed afterthe vertical centrifugation process-is is probably the result

Table 3 Individual content of phenolic compounds before and after vertical centrifugation storage and filtration expressed in mgkglowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredPhenolic alcoholsHydroxytyrosol 624plusmn 010a 615plusmn 010a ndash ndashTyrosol 387plusmn 007a 234plusmn 015c 285plusmn 002b 288plusmn 003b

Phenolic acidsp-coumaric acid 304plusmn 015a 169plusmn 009c 274plusmn 001b 142plusmn 005dFerulic acid 736plusmn 016a 532plusmn 013b 077plusmn 003c 087plusmn 001cCinnamic acid 170plusmn 008a 164plusmn 005a 104plusmn 004b 088plusmn 029b

Secoiridoids34-DHPEA-EDA (oleacein) 14157plusmn 368a 9463plusmn 032b 2893plusmn 037c 2995plusmn 092c34-DHPEA-EA 10814plusmn 211a 8527plusmn 218b 2799plusmn 029c 2898plusmn 056cp-HPEA-EDA (oleocanthal) 7518plusmn 298a 6230plusmn 290b 3272plusmn 032c 3274plusmn 024cp-HPEA-EA 2198plusmn 238a 1780plusmn 149b 1845plusmn 017b 1861plusmn 037b

LignansPinoresinol + acetoxypinoresinol 1456plusmn 137a 1405plusmn 165a 1160plusmn 084b 1145plusmn 046b

FlavonesLuteolin 767plusmn 029b 750plusmn 048bc 975plusmn 056a 676plusmn 050cApigenin 524plusmn 048b 449plusmn 031c 737plusmn 013a 699plusmn 023a

OthersVainillin 185plusmn 003a 167plusmn 007b 152plusmn 004c 156plusmn 009clowastValues are expressed as meanplusmn SD (a b c d) indicate the Fisherrsquos least significant differences (LSD) with statistically significant differences at 95confidence level

Journal of Food Quality 5

of the transfer of hydrophilic phenols from the oil to thewater phase Centrifugation led to a 229 reduction in thetotal content of phenolic compounds Similarly the contentof volatile compounds from the LOX pathway exhibited adecrease after washing although the loss was just of 9 Itshould be noted that a significant decrease of 533 of theethanol compound content was observed after verticalcentrifugation of the olive oil

-e most relevant results from the oil samples stored for25 days before filtration were a significant increase in theperoxide index (around 30) and a 78 decrease in theantioxidant capacity A small number of differences weredetected after oil filtration with no differences in the sensorycharacteristics -e total amount of phenolic compoundsand volatile compounds from the LOX pathway was similarin both filtered and unfiltered samples furthermore theantioxidant capacity exhibited a similar trend to the phenoliccompound content On the contrary the photosyntheticpigment content decreased after the filtration process

From these results it is concluded that the water ad-dition in the vertical centrifugation and the time of storage ofolive oils should be reduced in order to avoid the decrease ofthe antioxidant capacity and phenolics compounds

Abbreviations

3 4-DHPEA-EA aldehyde and hydroxylic forms ofoleuropein aglycone

3 4-DHPEA-EDA(oleacein)

dialdehyde form of decarboxymethyloleuropein aglycone

DPPH 2 2-diphenyl-1-picrylhydrazylEVOO extra virgin olive oilLSD least significant differenceMI maturity indexMUFA monounsaturated fatty acidp-HPEA-EA aldehyde and hydroxylic forms of

ligstroside aglyconep-HPEA-EDA(oleocanthal)

dialdehyde form of decarboxymethylligstroside aglycone

VC vertical centrifugeVOO virgin olive oil

Data Availability

-e data used to support the findings of this study are in-cluded within the article

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-e authors are grateful to the Department of EconomyInnovation and Science of the Andalusian Regional Gov-ernment for the financial help provided through ResearchProject of Excellence PI11-AGR-7726 -e authors wouldalso like to acknowledge MONVA SL and all the staff atldquoCortijo Virgen de los Milagrosrdquo Mancha Real Jaen Spainfor their kindness and attention -e technical and human

support provided by CICT of Universidad de Jaen (UJAMINECO Junta de Andalucıa FEDER) is also gratefullyacknowledged

Supplementary Materials

Figure S1 Comparison of the volatile (A) and phenolic (B)compound content in oil before and after centrifugationData at the decanter exit and centrifuge exit -e error barsshow the standard deviation Figure S2 Comparison of thevolatile (A) and phenolic (B) compound content in un-filtered and filtered oil Data at the unfiltered and filteredoils -e error bars show the standard deviation (Supple-mentary Materials)

References

[1] M Covas ldquoOlive oil and the cardiovascular systemrdquo Phar-macological Research vol 55 no 3 pp 175ndash186 2007

[2] L Parkinson and S Cicerale ldquo-e health benefiting mecha-nisms of virgin olive oil phenolic compoundsrdquo Moleculesvol 21 no 12 p 1734 2016

[3] EEC European Commission Regulation 4322012 Establishinga List of Permitted Health Claims Made on Foods Other than9ose Referring to the Reduction of Disease Risk and toChildrenrsquos Development and Health Vol 136 EEC BrusselsBelgium 2012

[4] M Z Tsimidou and D Boskou ldquo-e health claim on ldquoolive oilpolyphenolsrdquo and the need for meaningful terminology andeffective analytical protocolsrdquo European Journal of LipidScience and Technology vol 117 no 8 pp 1091ndash1094 2015

[5] G Altieri F Genovese A Tauriello and G C Di RenzoldquoInnovative plant for the separation of high quality virginolive oil (VOO) at industrial scalerdquo Journal of Food Engi-neering vol 166 pp 325ndash334 2015

[6] P S Rodis V T Karathanos and A Mantzavinou ldquoParti-tioning of olive oil antioxidants between oil and water pha-sesrdquo Journal of Agricultural and Food Chemistry vol 50 no 3pp 596ndash601 2002

[7] L Guerrini O Luca Pantani and A Parenti ldquo-e impact ofvertical centrifugation on olive oil qualityrdquo Journal of FoodProcess Engineering vol 40 no 3 2017

[8] A Parenti P Spugnoli P Masella and L Calamai ldquoInfluenceof the extraction process on dissolved oxygen in olive oilrdquoEuropean Journal of Lipid Science and Technology vol 109no 12 pp 1180ndash1185 2007

[9] P Masella A Parenti P Spugnoli and L Calamai ldquoVerticalcentrifugation of virgin olive oil under inert gasrdquo EuropeanJournal of Lipid Science and Technology vol 114 no 9pp 1094ndash1096 2012

[10] S Alcala M T Ocantildea J R Cardenas et al ldquoAlkyl esterscontent and other quality parameters in oil mill a responsesurface methodology studyrdquo European Journal of Lipid Sci-ence and Technology vol 119 no 1 article 1600026 2017

[11] A Gila G Beltran M A Bejaoui M P Aguilera andA Jimenez ldquoHow clarification systems can affect virgin oliveoil composition and quality at industrial scalerdquo EuropeanJournal of Lipid Science and Technology vol 119 no 10 article1600479 2017

[12] J M Garcıa K Yousfi R Mateos M Olmo and A CertldquoReduction of oil bitterness by heating of olive (Olea euro-paea) fruitsrdquo Journal of Agricultural and Food Chemistryvol 49 no 9 pp 4231ndash4235 2001

6 Journal of Food Quality

presented in Tables 1ndash3 After oil filtration slight but significantdifferences were observed-e acidity andK232 value decreasedslightly and the peroxide index increased by 122 In contrastthe photosynthetic pigment content was reduced during thefiltration process -e chlorophyll concentration decreased by478 in relation to the unfiltered oil and the carotenoidconcentration decreased by 368 -is means that the cel-lulose acetate filter collects a very important fraction of pho-tosynthetic pigments -ese results are consistent with thosereported by Gordillo et al [34] and Brkic Bubola et al [24]According to the quality parameters determined the olive oilcategory was still EVOO for all the samples as per the EEC [30]Although the quality parameters underwent some changes thecategory of the olive oil was not changed by the filtrationprocess-e antioxidant capacity was also similar in both cases

-e results of the volatile compounds are presented inTable 2 and are represented in Figure S2(A) -e volatilecompounds were analyzed separately to detect any differencesbetween the unfiltered and filtered samples Overall no majordifferences were observed between the two samples except forsome compounds (E)-2-Hexenal (Z)-3-hexenol and (Z)-3-hexenyl acetate were found in greater proportion in theunfiltered sample in contrast (Z)-2-pentenol 3-pentanoneand (E)-2-pentenal were detected in smaller proportion in theunfiltered sample -e amount of six-carbon-atom volatilecompounds decreased after filtration however the amount offive-carbon-atom volatile compounds increased after thefiltration process Although the observed differences areminor they still reveal a slight trend -ese results are similarto those previously reported in the literature by Bottino et al[23] and Brkic Bubola et al [24]

-e results obtained from the analysis of phenoliccompounds are shown in Table 3 and are represented inFigure S2(B) -e total amount of phenolic compounds wassimilar in both filtered and unfiltered samples Certain

similarities exist in both samples except for some particularcompounds Larger amounts of luteolin and p-coumaric acidwere detected in the unfiltered sample results similar tothose obtained by Bakhouche et al [19] that finds a re-duction of phenolic alcohols and flavones On the otherhand oleacin and 3 4-DHPEA-EA were found in smallerproportion in the unfiltered sample although they are notsignificant differences According to Gomez-Caravaca et al[35] the content of phenolic compounds slightly increasesafter the filtration process which may be due to the removalof water from the oil thus increasing the concentration ofdissolved substances in the oil

All other phenolic compounds presented no differencesin the filtered and unfiltered samples It should be noted thatthere are some investigations changing the filtering condi-tions such as that of Lozano-Sanchez et al [22] and findsome differences in the oils Also the type of filter used in thefiltration process can be affected the content of phenoliccompounds according to results obtained by Bakhoucheet al [19] and Gomez-Caravaca et al [35]

4 Conclusion

-e use of centrifugation storage (in order to decant) andfiltration in an industrial olive mill have the function of toclean and to clarify olive oils -e olive oil category was notchanged after the centrifugation storage and filtrationprocesses with slight changes in the fruitiness bitterness andpungency However centrifugation storage and filtrationproduced some significant changes found in the qualityparameters and minor composition

A relevant result was how the content of phenoliccompounds was affected by centrifugation A reduction inthe concentration of these compounds was observed afterthe vertical centrifugation process-is is probably the result

Table 3 Individual content of phenolic compounds before and after vertical centrifugation storage and filtration expressed in mgkglowast

Decanter exit Centrifuge exitbeginning of storage Unfilteredend of storage FilteredPhenolic alcoholsHydroxytyrosol 624plusmn 010a 615plusmn 010a ndash ndashTyrosol 387plusmn 007a 234plusmn 015c 285plusmn 002b 288plusmn 003b

Phenolic acidsp-coumaric acid 304plusmn 015a 169plusmn 009c 274plusmn 001b 142plusmn 005dFerulic acid 736plusmn 016a 532plusmn 013b 077plusmn 003c 087plusmn 001cCinnamic acid 170plusmn 008a 164plusmn 005a 104plusmn 004b 088plusmn 029b

Secoiridoids34-DHPEA-EDA (oleacein) 14157plusmn 368a 9463plusmn 032b 2893plusmn 037c 2995plusmn 092c34-DHPEA-EA 10814plusmn 211a 8527plusmn 218b 2799plusmn 029c 2898plusmn 056cp-HPEA-EDA (oleocanthal) 7518plusmn 298a 6230plusmn 290b 3272plusmn 032c 3274plusmn 024cp-HPEA-EA 2198plusmn 238a 1780plusmn 149b 1845plusmn 017b 1861plusmn 037b

LignansPinoresinol + acetoxypinoresinol 1456plusmn 137a 1405plusmn 165a 1160plusmn 084b 1145plusmn 046b

FlavonesLuteolin 767plusmn 029b 750plusmn 048bc 975plusmn 056a 676plusmn 050cApigenin 524plusmn 048b 449plusmn 031c 737plusmn 013a 699plusmn 023a

OthersVainillin 185plusmn 003a 167plusmn 007b 152plusmn 004c 156plusmn 009clowastValues are expressed as meanplusmn SD (a b c d) indicate the Fisherrsquos least significant differences (LSD) with statistically significant differences at 95confidence level

Journal of Food Quality 5

of the transfer of hydrophilic phenols from the oil to thewater phase Centrifugation led to a 229 reduction in thetotal content of phenolic compounds Similarly the contentof volatile compounds from the LOX pathway exhibited adecrease after washing although the loss was just of 9 Itshould be noted that a significant decrease of 533 of theethanol compound content was observed after verticalcentrifugation of the olive oil

-e most relevant results from the oil samples stored for25 days before filtration were a significant increase in theperoxide index (around 30) and a 78 decrease in theantioxidant capacity A small number of differences weredetected after oil filtration with no differences in the sensorycharacteristics -e total amount of phenolic compoundsand volatile compounds from the LOX pathway was similarin both filtered and unfiltered samples furthermore theantioxidant capacity exhibited a similar trend to the phenoliccompound content On the contrary the photosyntheticpigment content decreased after the filtration process

From these results it is concluded that the water ad-dition in the vertical centrifugation and the time of storage ofolive oils should be reduced in order to avoid the decrease ofthe antioxidant capacity and phenolics compounds

Abbreviations

3 4-DHPEA-EA aldehyde and hydroxylic forms ofoleuropein aglycone

3 4-DHPEA-EDA(oleacein)

dialdehyde form of decarboxymethyloleuropein aglycone

DPPH 2 2-diphenyl-1-picrylhydrazylEVOO extra virgin olive oilLSD least significant differenceMI maturity indexMUFA monounsaturated fatty acidp-HPEA-EA aldehyde and hydroxylic forms of

ligstroside aglyconep-HPEA-EDA(oleocanthal)

dialdehyde form of decarboxymethylligstroside aglycone

VC vertical centrifugeVOO virgin olive oil

Data Availability

-e data used to support the findings of this study are in-cluded within the article

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-e authors are grateful to the Department of EconomyInnovation and Science of the Andalusian Regional Gov-ernment for the financial help provided through ResearchProject of Excellence PI11-AGR-7726 -e authors wouldalso like to acknowledge MONVA SL and all the staff atldquoCortijo Virgen de los Milagrosrdquo Mancha Real Jaen Spainfor their kindness and attention -e technical and human

support provided by CICT of Universidad de Jaen (UJAMINECO Junta de Andalucıa FEDER) is also gratefullyacknowledged

Supplementary Materials

Figure S1 Comparison of the volatile (A) and phenolic (B)compound content in oil before and after centrifugationData at the decanter exit and centrifuge exit -e error barsshow the standard deviation Figure S2 Comparison of thevolatile (A) and phenolic (B) compound content in un-filtered and filtered oil Data at the unfiltered and filteredoils -e error bars show the standard deviation (Supple-mentary Materials)

References

[1] M Covas ldquoOlive oil and the cardiovascular systemrdquo Phar-macological Research vol 55 no 3 pp 175ndash186 2007

[2] L Parkinson and S Cicerale ldquo-e health benefiting mecha-nisms of virgin olive oil phenolic compoundsrdquo Moleculesvol 21 no 12 p 1734 2016

[3] EEC European Commission Regulation 4322012 Establishinga List of Permitted Health Claims Made on Foods Other than9ose Referring to the Reduction of Disease Risk and toChildrenrsquos Development and Health Vol 136 EEC BrusselsBelgium 2012

[4] M Z Tsimidou and D Boskou ldquo-e health claim on ldquoolive oilpolyphenolsrdquo and the need for meaningful terminology andeffective analytical protocolsrdquo European Journal of LipidScience and Technology vol 117 no 8 pp 1091ndash1094 2015

[5] G Altieri F Genovese A Tauriello and G C Di RenzoldquoInnovative plant for the separation of high quality virginolive oil (VOO) at industrial scalerdquo Journal of Food Engi-neering vol 166 pp 325ndash334 2015

[6] P S Rodis V T Karathanos and A Mantzavinou ldquoParti-tioning of olive oil antioxidants between oil and water pha-sesrdquo Journal of Agricultural and Food Chemistry vol 50 no 3pp 596ndash601 2002

[7] L Guerrini O Luca Pantani and A Parenti ldquo-e impact ofvertical centrifugation on olive oil qualityrdquo Journal of FoodProcess Engineering vol 40 no 3 2017

[8] A Parenti P Spugnoli P Masella and L Calamai ldquoInfluenceof the extraction process on dissolved oxygen in olive oilrdquoEuropean Journal of Lipid Science and Technology vol 109no 12 pp 1180ndash1185 2007

[9] P Masella A Parenti P Spugnoli and L Calamai ldquoVerticalcentrifugation of virgin olive oil under inert gasrdquo EuropeanJournal of Lipid Science and Technology vol 114 no 9pp 1094ndash1096 2012

[10] S Alcala M T Ocantildea J R Cardenas et al ldquoAlkyl esterscontent and other quality parameters in oil mill a responsesurface methodology studyrdquo European Journal of Lipid Sci-ence and Technology vol 119 no 1 article 1600026 2017

[11] A Gila G Beltran M A Bejaoui M P Aguilera andA Jimenez ldquoHow clarification systems can affect virgin oliveoil composition and quality at industrial scalerdquo EuropeanJournal of Lipid Science and Technology vol 119 no 10 article1600479 2017

[12] J M Garcıa K Yousfi R Mateos M Olmo and A CertldquoReduction of oil bitterness by heating of olive (Olea euro-paea) fruitsrdquo Journal of Agricultural and Food Chemistryvol 49 no 9 pp 4231ndash4235 2001

6 Journal of Food Quality

of the transfer of hydrophilic phenols from the oil to thewater phase Centrifugation led to a 229 reduction in thetotal content of phenolic compounds Similarly the contentof volatile compounds from the LOX pathway exhibited adecrease after washing although the loss was just of 9 Itshould be noted that a significant decrease of 533 of theethanol compound content was observed after verticalcentrifugation of the olive oil

-e most relevant results from the oil samples stored for25 days before filtration were a significant increase in theperoxide index (around 30) and a 78 decrease in theantioxidant capacity A small number of differences weredetected after oil filtration with no differences in the sensorycharacteristics -e total amount of phenolic compoundsand volatile compounds from the LOX pathway was similarin both filtered and unfiltered samples furthermore theantioxidant capacity exhibited a similar trend to the phenoliccompound content On the contrary the photosyntheticpigment content decreased after the filtration process

From these results it is concluded that the water ad-dition in the vertical centrifugation and the time of storage ofolive oils should be reduced in order to avoid the decrease ofthe antioxidant capacity and phenolics compounds

Abbreviations

3 4-DHPEA-EA aldehyde and hydroxylic forms ofoleuropein aglycone

3 4-DHPEA-EDA(oleacein)

dialdehyde form of decarboxymethyloleuropein aglycone

DPPH 2 2-diphenyl-1-picrylhydrazylEVOO extra virgin olive oilLSD least significant differenceMI maturity indexMUFA monounsaturated fatty acidp-HPEA-EA aldehyde and hydroxylic forms of

ligstroside aglyconep-HPEA-EDA(oleocanthal)

dialdehyde form of decarboxymethylligstroside aglycone

VC vertical centrifugeVOO virgin olive oil

Data Availability

-e data used to support the findings of this study are in-cluded within the article

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-e authors are grateful to the Department of EconomyInnovation and Science of the Andalusian Regional Gov-ernment for the financial help provided through ResearchProject of Excellence PI11-AGR-7726 -e authors wouldalso like to acknowledge MONVA SL and all the staff atldquoCortijo Virgen de los Milagrosrdquo Mancha Real Jaen Spainfor their kindness and attention -e technical and human

support provided by CICT of Universidad de Jaen (UJAMINECO Junta de Andalucıa FEDER) is also gratefullyacknowledged

Supplementary Materials

Figure S1 Comparison of the volatile (A) and phenolic (B)compound content in oil before and after centrifugationData at the decanter exit and centrifuge exit -e error barsshow the standard deviation Figure S2 Comparison of thevolatile (A) and phenolic (B) compound content in un-filtered and filtered oil Data at the unfiltered and filteredoils -e error bars show the standard deviation (Supple-mentary Materials)

References

[1] M Covas ldquoOlive oil and the cardiovascular systemrdquo Phar-macological Research vol 55 no 3 pp 175ndash186 2007

[2] L Parkinson and S Cicerale ldquo-e health benefiting mecha-nisms of virgin olive oil phenolic compoundsrdquo Moleculesvol 21 no 12 p 1734 2016

[3] EEC European Commission Regulation 4322012 Establishinga List of Permitted Health Claims Made on Foods Other than9ose Referring to the Reduction of Disease Risk and toChildrenrsquos Development and Health Vol 136 EEC BrusselsBelgium 2012

[4] M Z Tsimidou and D Boskou ldquo-e health claim on ldquoolive oilpolyphenolsrdquo and the need for meaningful terminology andeffective analytical protocolsrdquo European Journal of LipidScience and Technology vol 117 no 8 pp 1091ndash1094 2015

[5] G Altieri F Genovese A Tauriello and G C Di RenzoldquoInnovative plant for the separation of high quality virginolive oil (VOO) at industrial scalerdquo Journal of Food Engi-neering vol 166 pp 325ndash334 2015

[6] P S Rodis V T Karathanos and A Mantzavinou ldquoParti-tioning of olive oil antioxidants between oil and water pha-sesrdquo Journal of Agricultural and Food Chemistry vol 50 no 3pp 596ndash601 2002

[7] L Guerrini O Luca Pantani and A Parenti ldquo-e impact ofvertical centrifugation on olive oil qualityrdquo Journal of FoodProcess Engineering vol 40 no 3 2017

[8] A Parenti P Spugnoli P Masella and L Calamai ldquoInfluenceof the extraction process on dissolved oxygen in olive oilrdquoEuropean Journal of Lipid Science and Technology vol 109no 12 pp 1180ndash1185 2007

[9] P Masella A Parenti P Spugnoli and L Calamai ldquoVerticalcentrifugation of virgin olive oil under inert gasrdquo EuropeanJournal of Lipid Science and Technology vol 114 no 9pp 1094ndash1096 2012

[10] S Alcala M T Ocantildea J R Cardenas et al ldquoAlkyl esterscontent and other quality parameters in oil mill a responsesurface methodology studyrdquo European Journal of Lipid Sci-ence and Technology vol 119 no 1 article 1600026 2017

[11] A Gila G Beltran M A Bejaoui M P Aguilera andA Jimenez ldquoHow clarification systems can affect virgin oliveoil composition and quality at industrial scalerdquo EuropeanJournal of Lipid Science and Technology vol 119 no 10 article1600479 2017

[12] J M Garcıa K Yousfi R Mateos M Olmo and A CertldquoReduction of oil bitterness by heating of olive (Olea euro-paea) fruitsrdquo Journal of Agricultural and Food Chemistryvol 49 no 9 pp 4231ndash4235 2001

6 Journal of Food Quality

[13] P Masella A Parenti P Spugnoli and L Calamai ldquoInfluenceof vertical centrifugation on extra virgin olive oil qualityrdquoJournal of the American Oil Chemistsrsquo Society vol 86 no 11pp 1137ndash1140 2009

[14] A Jimenez M Hermoso and M Uceda ldquoElaboracion delaceite de oliva virgen mediante sistema continuo en dos fasesInfluencia de diferentes variables del proceso en algunosparametros relacionados con la calidad del aceiterdquo GrasasAceites vol 46 no 4-5 pp 299ndash303 1995

[15] A Cert J Alba M C Perez-Camino and F HidalgoldquoInfluencia de los sistemas de extraccion sobre las car-acterısticas y los componentes menores del aceite de olivavirgen extrardquo Olivae vol 79 pp 41ndash50 1999

[16] M Fortini M Migliorini C Cherubini et al ldquoShelf life andquality of olive oil filtered without vertical centrifugationrdquoEuropean Journal of Lipid Science and Technology vol 118no 8 pp 1213ndash1222 2015

[17] J Lozano-Sanchez L Cerretani A Bendini A Segura-Car-retero and A Fernandez-Gutierrez ldquoFiltration process ofextra virgin olive oil effect on minor components oxidativestability and sensorial and physicochemical characteristicsrdquoTrends in Food Science amp Technology vol 21 no 4 pp 201ndash211 2010

[18] K B Bubola and O Koprivnjak ldquoChapter 31-influence offiltration on composition of olive oilsrdquo in Processing andImpact on Active Components in Food V Preedy Edpp 259ndash265 Academic Press San Diego CA USA 2015

[19] A Bakhouche J Lozano-Sanchez C A Ballus et al ldquoA newextraction approach to correct the effect of apparent increasein the secoiridoid content after filtration of virgin olive oilrdquoTalanta vol 127 pp 18ndash25 2014

[20] K Brkic Bubola M Lukic I Mofardin A Butumovic andO Koprivnjak ldquoFiltered vs naturally sedimented and dec-anted virgin olive oil during storage effect on quality andcompositionrdquo LWT vol 84 pp 370ndash377 2017

[21] G Fregapane V Lavelli S Leon J Kapuralin andM Desamparados Salvador ldquoEffect of filtration on virgin oliveoil stability during storagerdquo European Journal of Lipid Scienceand Technology vol 108 no 2 pp 134ndash142 2006

[22] J Lozano-Sanchez L Cerretani A Bendini T Gallina-Toschi A Segura-Carretero and A Fernandez-GutierrezldquoNew filtration systems for extra-virgin olive oil effect onantioxidant compounds oxidative stability and physico-chemical and sensory propertiesrdquo Journal of Agricultural andFood Chemistry vol 60 no 14 pp 3754ndash3762 2012

[23] A Bottino G Capannelli A Mattei P Rovellini andP Zunin ldquoEffect of membrane filtration on the flavor of virginolive oilrdquo European Journal of Lipid Science and Technologyvol 110 no 12 pp 1109ndash1115 2008

[24] K Brkic Bubola O Koprivnjak and B Sladonja ldquoInfluence offiltration on volatile compounds and sensory profile of virginolive oilsrdquo Food Chemistry vol 132 no 1 pp 98ndash103 2012

[25] F Espınola M Moya D G Fernandez and E CastroldquoImproved extraction of virgin olive oil using calcium car-bonate as coadjuvant extractantrdquo Journal of Food Engineeringvol 92 no 1 pp 112ndash118 2009

[26] EEC European Commission Regulation 25681991 on theCharacteristics of Olive Oil and Olive-esidue Oil and on theRelevant Methods of AnalysisVol 248 EEC Brussels Belgium1991

[27] I M Minguez-Mosquera L Rejano-Navarro B Gandul-Rojas A H Sanchez-Gomez and J Garrido-FernandezldquoColor-pigment correlation in virgin olive oilrdquo Journal of

American Oil Chemistsrsquo Society vol 68 no 11 pp 809ndash8131991

[28] A M Vidal S Alcala A de Torres M Moya and F EspınolaldquoUse of talc in oil mills influence on the quality and content ofminor compounds in olive oilsrdquo LWT vol 98 pp 31ndash382018

[29] IOCDetermination of Biophenols in Olive Oils by HPLC IOCMadrid Spain 2017

[30] EEC European Commission Regulation 20952016 AmendingRegulation (EEC) no 256891 on the Characteristics of OliveOil and Olive-Residue Oil and on the Relevant Methods ofAnalysis Vol 326 EEC Brussels Belgium 2016

[31] N Rodrigues L G Dias A C A Veloso J A Pereira andA M Peres ldquoMonitoring olive oils quality and oxidativeresistance during storage using an electronic tonguerdquo LWTvol 73 pp 683ndash692 2016

[32] F Gutierrez and J L Fernandez ldquoDeterminant parametersand components in the storage of virgin olive oil Prediction ofstorage time beyond which the oil is no longer of ldquoextrardquoqualityrdquo Journal of Agricultural and Food Chemistry vol 50no 3 pp 571ndash577 2002

[33] K Kotsiou and M Tasioula-Margari ldquoMonitoring the phe-nolic compounds of Greek extra-virgin olive oils duringstoragerdquo Food Chemistry vol 200 pp 255ndash262 2016

[34] B Gordillo L Ciaccheri A G Mignani M L Gonzalez-Miret and F J Heredia ldquoInfluence of turbidity grade on colorand appearance of virgin olive oilrdquo Journal of American OilChemistsrsquo Society vol 88 no 9 pp 1317ndash1327 2011

[35] A M Gomez-Caravaca L Cerretani A Bendini A Segura-Carretero A Fernandez-Gutierrez and G Lercker ldquoEffect offiltration systems on the phenolic content in virgin olive oil byHPLC-DAD-MSDrdquo American Journal of Food Technologyvol 2 no 7 pp 671ndash678 2007

Journal of Food Quality 7

Hindawiwwwhindawicom

International Journal of

Volume 2018

Zoology

Hindawiwwwhindawicom Volume 2018

Anatomy Research International

PeptidesInternational Journal of

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Journal of Parasitology Research

GenomicsInternational Journal of

Hindawiwwwhindawicom Volume 2018

Hindawi Publishing Corporation httpwwwhindawicom Volume 2013Hindawiwwwhindawicom

The Scientific World Journal

Volume 2018

Hindawiwwwhindawicom Volume 2018

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Neuroscience Journal

Hindawiwwwhindawicom Volume 2018

BioMed Research International

Cell BiologyInternational Journal of

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Biochemistry Research International

ArchaeaHindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Genetics Research International

Hindawiwwwhindawicom Volume 2018

Advances in

Virolog y Stem Cells International

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Enzyme Research

Hindawiwwwhindawicom Volume 2018

International Journal of

MicrobiologyHindawiwwwhindawicom

Nucleic AcidsJournal of

Volume 2018

Submit your manuscripts atwwwhindawicom

Hindawiwwwhindawicom

International Journal of

Volume 2018

Zoology

Hindawiwwwhindawicom Volume 2018

Anatomy Research International

PeptidesInternational Journal of

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Journal of Parasitology Research

GenomicsInternational Journal of

Hindawiwwwhindawicom Volume 2018

Hindawi Publishing Corporation httpwwwhindawicom Volume 2013Hindawiwwwhindawicom

The Scientific World Journal

Volume 2018

Hindawiwwwhindawicom Volume 2018

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Neuroscience Journal

Hindawiwwwhindawicom Volume 2018

BioMed Research International

Cell BiologyInternational Journal of

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Biochemistry Research International

ArchaeaHindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Genetics Research International

Hindawiwwwhindawicom Volume 2018

Advances in

Virolog y Stem Cells International

Hindawiwwwhindawicom Volume 2018

Hindawiwwwhindawicom Volume 2018

Enzyme Research

Hindawiwwwhindawicom Volume 2018

International Journal of

MicrobiologyHindawiwwwhindawicom

Nucleic AcidsJournal of

Volume 2018

Submit your manuscripts atwwwhindawicom