E: Food Engineering & Physical Properties

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Introduction

Oil migration occurs in chocolate confectionery products thatcontain 2 or more oil-containing components adjacent to one

another (Wootton and others 1971; Wacquez 1975; Talbot 1990;Couzens and Wille 1997; Ziegleder 1997). Typical examples are com-posite chocolate products in which chocolate enrobes a fat-contain-ing center (for example, nut pastes, peanut butter, truffles). Differ-ent oil species migrate at varying rates and to different extentsduring storage depending on physical and chemical properties.The migration of the liquid lipid into the chocolate layer results inunwanted changes such as softening of the chocolate coating,hardening of the filling, and recrystallization of oil, which eventu-ally leads to fat bloom (Talbot 1995; Ziegleder 1997; Lonchamptand Hartel 2004). Oil migration also changes sensory properties,such as color and flavor (Ali and others 2001).

A number of contributing factors have been reported in the lit-erature. Temperature is a strong contributing factor; the rate of fatmigration increases as temperature increases. Ali and others (2001)modeled the migration rate of oil from a desiccated coconut andpalm mid-fraction blend through dark chocolate as a linear depen-dence, with the rate increasing as the temperature increased from18 °C to 30 °C. These researchers used nuclear magnetic resonance(NMR) to evaluate the solid fat content in the system over time asa function of temperature, as did Couzens and Wille (1997) andTalbot (1990). Magnetic resonance imaging (MRI), in contrast, pro-vides both spatial and temporal information and has been used instudies to differentiate between components (Duce and other1990; McCarthy 1994; Couzens and Wille 1997) and to monitor crys-tallization as lipid samples cooled (Simoneau and others 1992). Thesame samples can be followed over time because the MRI tech-nique is nondestructive. Guiheneuf and others (1997) documentedmigration profiles at 19 °C and 28 °C in a model system of hazel nut

oil and dark chocolate. The researchers suggested that the mech-anism of migration involves both diffusion of the liquid triacylglyc-erols and capillary attraction of the oil into the chocolate matrix.

Degree of temper was added as a contributing factor to oil migra-tion in a follow-up study by Miquel and others (2001) using darkchocolate and hazelnut oil. Oil concentration from MRI data wasplotted against the square root of time; rates were characterized bythe slope of the line. This approach is consistent with diffusion ofa component in a semi-infinite media (Crank 1975) and was alsoused by Ziegleder (1997). Although good temper provides the bestresistance to fat migration (Bolliger and others 1998), the temper-ing regime was reported to have no effect on the speed of the migra-tion (Miquel and others 2001). However, the degree of temper wasnot stated quantitatively for the low-temper and high-temper sam-ples. The researchers did report a different saturation concentra-tion in the under-tempered and well-tempered chocolate that washypothesized to be due to structural differences.

In the process of oil migration, 2 phenomena have been identi-fied: migration due to diffusion and/or capillary action and phasebehavior (Aguilera and others 2004; Ziegler and others 2004). Thefocus of the work by Ziegler and others (2004) was to discuss thechanges in equilibrium between solid and liquid phases during oilmigration that alter the fat phase structure. Implicit, however, isthat anything that decreases the solid fat content will increase themigration rate, including formulation. Lower solid fat content (SFC)products are softer and more prone to migration. The interactionbetween cocoa butter and milk fat is particularly important in de-fining the characteristics of milk chocolate. Bigalli (1988) stated thathigh levels of milk fat (for example, 20%) promote softening. Thedominant factor is due to the liquid fraction of milk fat, which be-haves almost as a straight dilution effect, similar to liquid nut oilssuch as peanut oil. Cocoa butter is simply diluted by these liquidoils rather than forming eutectics (Lonchampt and Hartel 2004).

As part of a larger study, Walter and Cornillon (2002) evaluated oilmigration in a model confectionery system of a layer of peanut but-ter over a layer of dark chocolate in an NMR tube. After 1 d, the NMRsignal from the chocolate region had higher signal intensity because

MS 20040759 Submitted 11/20/04, Revised 2/5/05, Accepted 3/2/05. The au-thors are with Dept. of Food Science and Technology, One Shields Ave, Univ.of California, Davis, Davis, CA 95616. Direct inquiries to author K.L.McCarthy (E-mail: klmccarthy@ucdavis.edu).

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Oil migration in chocolate . . .

of migration of liquid fat from peanut butter. After the 2nd day, a lowsignal intensity layer appeared in the sample at the interface of thepeanut butter and chocolate, which the researchers suggested wasa more complex mechanism of migration than diffusion alone.

This research addressed oil migration in a composite confection-ery product of milk chocolate and peanut butter paste. The objec-tive of this study was to identify and characterize important factorsimpacting oil migration in the model system. Proton density signalfrom oil was monitored during storage using MRI. The experimentalfactors were milk fat content, degree of temper, and storage tem-perature. In addition to these factors previously reported in the lit-erature as important to oil migration, 2 other factors were incorpo-rated: chocolate particle size and emulsifier concentration. Theexperimental responses were the rate of migration of the oil fromthe peanut butter paste to the chocolate and the overall change insignal intensity in the chocolate region due to increased liquid fat.

Materials and Methods

Sample preparation and experimental designSample preparation and experimental designSample preparation and experimental designSample preparation and experimental designSample preparation and experimental designThe model system was a 2-layer chocolate confectionery system.

A layer of milk chocolate was deposited into a 2.59-cm-dia × 3.78-cm-high sample container. A layer of peanut butter paste was de-posited on top of the solidified milk chocolate (Figure 1). Each layerwas approximately 1 cm high. Sample mass was 12.2 g with a stan-dard deviation of 0.3 g. The plastic container was sealed with an air-and moisture-tight lid.

Five different chocolate formulations and 1 peanut butter pasteformulation were used. The compositions of the chocolate formula-tions are given in Table 1. All chocolate formulations consisted of26.65% total fat and 76.35% total nonfat solids. The total nonfat sol-ids included 4.41% lactose, 11.57% cocoa liquor, and 8.70% nonfat drymilk. The standard chocolate (Formulation 1) consisted of 3.57%anhydrous milk fat (AMF), 0.3% lecithin, and 0.08% polyglycerylpolyricinoleate (PGPR), with a mean particle size of 45 �m. Formula-tions vary in particle size, AMF, and emulsifier level. To change AMFcontent in formulations, part of the cocoa butter was replaced withAMF to maintain the total fat content. The mean particle size of For-mulation 2 was 60 �m. Formulations 3 and 4 contained 0% and 10%AMF, respectively. Formulation 5 had no emulsifier added. The pea-nut butter paste contained 36.20% fat, 61.84% nonfat solids, and1.96% moisture; the mean particle size was 39 �m.

The chocolate samples were prepared to 3 different degrees oftemper (under-, well-, and over-tempered) to study the effect oftempering on oil migration of peanut oil into the milk chocolate. Foreach formulation, the milk chocolate paste was melted (T > 38 °C)in a temper machine (Revolation 1, ChocoVision Corp., Pough-keepsie, N.Y., U.S.A.) and then cooled gradually to 30 °C. Coolingcurves were monitored using a chocolate temper unit (CTU) valueand slope values from the temper meter (Model 205 Portable Choc-

olate Temper Meter, Tricor Systems Inc., Elgin, Ill., U.S.A.). Thedegree of temper was evaluated by an industrial standard in whichthe slope value between –0.6 and 0.6 is considered well-tempered,above 0.6 is under-tempered, and below –0.6 is over-tempered(Bolliger and others 1998). The degree of temper was controlled byadding seed chocolate crystals based on a standard curve devel-oped for each milk chocolate formulation.

The samples were stored in controlled environment chambers at20 ± 0.5 °C and 30 ± 0.5 ° C. The temperature of 20 °C representsnormal storage conditions; the temperature of 30 °C representsaccelerated shelf-life test. The samples were removed from thecontrolled environment chambers and evaluated at room temper-ature. Samples were at room temperature no longer than 20 minand then returned to storage conditions.

Three full factorial designs were used to evaluate the followingcombinations of factors: (1) chocolate particle size (Formulations 1and 2), degree of temper, and storage temperature; (2) AMF content(Formulations 1, 3, and 4), degree of temper, and storage tempera-ture; and (3) emulsifier concentration (Formulations 1 and 5), degreeof temper, and storage temperature. The experimental designs wereperformed with 2 levels each of particle size, emulsifier concentration,and temperature; 3 levels were used for degree of temper and AMFcontent. Replicates were performed to confirm the effect of chocolateparticle size, AMF content, and emulsifier concentration.

MRI measurementsMRI measurementsMRI measurementsMRI measurementsMRI measurementsOne-dimensional signal intensity profiles across the center of

the sample container were obtained from 1H signal (liquid lipid)using a 7T superconducting magnet in conjunction with a Biospecconsole (Bruker Biospin MRI Inc., Billerica, Mass., U.S.A.), whichcorresponds to 300 MHz for 1H-resonance frequency. A spin echoimaging pulse sequence without phase encoding was used to ac-quire 1-dimensional MR images (that is, signal intensity profiles),as described by McCarthy (1994) and Callaghan (1991). The fieldof view was 6.4 cm with a slice thickness of 8 mm, and echo time was4.9 ms; 256 data points (pixels) were acquired for each echo and 8echoes were averaged. The resolution was 250-�m /pixel.

Three types of standards were prepared in sample containers: 100%milk chocolate (Formulation 1), 100% peanut butter paste, and a mix-ture of powdered cane sugar (30% w/w) in peanut oil. The powderedsugar/peanut oil standard was more time-invariant than the peanutbutter paste standard and gave signal intensity values intermediateto the milk chocolate standard (low) and the peanut butter paste stan-dard (high). Therefore, MRI signal intensities from the model confec-tionery system were normalized with the sugar/peanut oil standard,obtained on the same day; this procedure compensated for day-to-day variations of the spectrometer signal. The data at the initial time(t = 0) were used to identify the chocolate region and the peanut butterregion in each sample container (Figure 2a). At that point, the choco-late and peanut butter regions were clearly identifiable, both in the 1-dimensional profile (Figure 2a) and in the corresponding image (Fig-

Table 1—Composition of the 5 chocolate formulations

Particle size Emulsifier

of chocolate AMF concentration (%)a

Formulation (�����m) content (%) Lecithin PGPR

1 45 3.57 0.30 0.082 60 3.57 0.40 0.113 45 0 0.40 0.114 45 10 0.40 0.115 45 3.57 0 0

aAMF = anhydrous milk fat; PGPR = polyglyceryl polyricinoleate.

Figure 1—Schematicdiagram of themodel chocolateconfectionery system

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Oil migration in chocolate . . .

ure 2b). The color map for the MR image is inverted gray scale, whichmeans low proton signal intensity is bright and high proton signal in-tensity is dark. The spatial regions were designated and used through-out the study to evaluate the average signal intensity due to chocolateand due to the peanut butter paste over the experimental timeframeof 15 wk. Data analysis was performed using MATLAB 6.5 software(Mathworks, Natick, Mass., U.S.A.).

Results and Discussion

Two-dimensional cross-sectional images provided quantitativeinformation on oil migration. Representative images of different

chocolate particle size samples after 11 d of storage are displayed inFigure 3. An image of the sugar/peanut oil standard, designated asPO (for peanut oil), is included to provide reference signal intensityvalues. Two distinct regions are visible in the 20 °C samples. Thechocolate region is at the bottom of the sample container with lowersignal intensity; the peanut butter paste is the top layer in the sam-ple container with higher signal intensity. Both the 20 °C samples andsugar/peanut oil standard show phase separation of the liquid oiland the bulk material. This phase separation had occurred by day 1of imaging (day 0 was the initial time, t = 0). Although the phase sep-aration also occurred in the 30 °C samples, the oil layer had reab-sorbed into the bulk material by day 11. As a general comment, thereare signal intensity variations in the peanut butter region; the heter-ogeneity was due in part to a small amount of air entrapped duringsample preparation of the viscous paste.

At day 11, very little oil migration was evident in the samples storedat 20 °C, as illustrated in Figure 3. Both the chocolate and peanut but-ter regions had virtually the same signal intensity that was evident onday 1 of imaging. In contrast, the images of the samples stored at 30 °Cillustrate the effect of oil migration on signal intensity (Figure 3). Thechocolate region has increased in signal intensity due to the liquid lip-id, especially at the interface region between the peanut butter pasteand the chocolate. As the oil moved from the peanut butter layer to thechocolate, the signal was depleted in the peanut butter layer. The rateof oil migration at 30 °C was higher in the 10% AMF sample (Figure 3b)than with the 0% AMF sample (Figure 3a).

Figure 4, 5, and 6 illustrate the change in relative signal intensityover time for the well-tempered samples. Figure 4 corresponds toExperimental Design 1, which evaluated the effect of chocolate par-ticle size. Figure 5 corresponds to Experimental Design 2, which eval-uated the effect of anhydrous milk fat content. Figure 6 correspondsto Experimental Design 3, which evaluated the effect of emulsifierlevel. The data in these figures are viewed in terms of 2 regions: theupper region is the signal from the peanut butter paste and desig-nated by dark markers, and the lower region is the signal intensityfrom the chocolate region and designated by open markers. For boththe chocolate region and the peanut butter region, the signal inten-sity values have been summed, normalized by the sugar/peanut oilstandard acquired on the same imaging day, and multiplied by100%. The normalization was performed in this way to ensure thatpossible phase changes by the lipid component would not bemasked. In each experimental design, the signal intensity of thepeanut butter paste decreased over time as the signal intensity of thechocolate increased. The change was more rapid and more distinctfor the samples stored at 30 °C than for the samples stored at 20 °C.

Figure 2—Representative magnetic resonance imaging(MRI) information for the chocolate confectionery systemat the initial time (t = 0), (a) 1-dimensional signal intensityprofile and (b) MR image; the darker the gray, the higherthe proton signal.

Figure 3—Two-dimensional images of samples after 11 dof storage for (a) 0% anhydrous milk fat (AMF) at 20 °C andat 30 °C, and (b) 10% AMF at 20 °C and at 30 °C. The im-age of the sugar/peanut oil standard is designated PO.

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At 30 °C, the oil migration progressed primarily within the 1st 2 wk,and oil concentration in the chocolate region reached a constant levelby 3 wk. In contrast, migration was much slower at 20 °C; the signalintensity had not reached a constant value after 106 d of storage. Togive a quantitative understanding of the extent (or amount) of oilmigration, Table 2 gives signal intensity values at day 1 (S1), finalconstant signal intensity values (Sf) in the chocolate region, theirdifference (Sf – S1), and the fractional change of the liquid fat signalrelative to the signal intensity at day 1 for the under-, well-, and over-tempered chocolate samples stored at 30 °C. The greatest change insignal intensity over time occurred for the 60-�m particle size (high-

level particle size). The least change in signal intensity over timeoccurred for the 10% AMF sample (high-level AMF). The greatest frac-tional change occurred for the 0% AMF sample.

To evaluate migration rates, the relative signal intensity (relativeto the sugar/peanut oil standard) for the chocolate region was plot-ted against the square root of time. As stated in the Introduction,this approach is consistent with diffusion of a component in asemi-infinite media; in addition, the relationship is consistent withcapillary flow (Aguilera and others 2004). Figure 7 illustrates thechange in signal intensities for each experimental design: Figure 7aillustrates particle size effect (Experimental Design 1), Figure 7billustrates the effect of AMF content (Experimental Design 2), andFigure 7c illustrates the effect of emulsifier content (ExperimentalDesign 3). The high level of each of these factors (particle size, AMFcontent, and emulsifier content) is given by dark markers. For eachexperimental design, the high level of these factors yielded higheroverall content of liquid lipid. A linear regression was performed onthe linear region of the signal intensity versus square root of timeplots. For each set of data, the time frame was 14 d. The value of theslope, which quantifies migration rate, the intercept, and the coef-ficient of determination (R2) are given in Table 3 for the well-tem-pered samples. The R2 values for the 20 °C storage samples wereconsiderably lower than for the 30 °C storage samples. The lowervalues are due to a weaker linear relationship (slope near zero) rath-er than scatter in the experimental data. The rate of migration isclearly a strong function of temperature; slope values at 30 °C stor-age differ by a factor of 10 from the slope values of samples storedat 20 °C. In addition, the rate of migration increased as particle sizeincreased. Analysis of variance (ANOVA) was performed to deter-mine statistically significant differences in the values of the re-sponses due to each of the 5 experimental factors.

SSSSStatistical analysis—ANOtatistical analysis—ANOtatistical analysis—ANOtatistical analysis—ANOtatistical analysis—ANOVVVVVAAAAAThree-way ANOVA was performed for each experimental design;

the main effects and 2-way interactions were evaluated for eachdesign at a level of significance of � = 0.05. The 3 responses wererate of change of signal intensity from liquid fat in the chocolatephase (slope of the linear regression), amount of change of signal

Table 2—Signal intensity from the chocolate region on day1 (S1), the constant level after storage (Sf), their difference,and the fractional change of the liquid fat signal relativeto the signal intensity at day 1 for samples stored at 30 °Ca

Formulation Temper S1 Sf Sf – S1 (Sf – S1)/S1

1 Under 16.07 31.53 15.46 0.960.3% emulsifier Well 15.46 31.63 16.16 1.05

45-�m particle size Over 15.27 31.85 16.58 1.093.57% AMF Mean 15.06 31.67 16.06 1.03

Under 14.89 32.33 17.44 1.172 Well 16.39 33.04 16.65 1.02

60-�m particle size Over 14.50 31.99 17.50 1.21Mean 15.26 32.45 17.20 1.13

Under 8.92 23.55 14.63 1.643 Well 9.08 25.77 16.69 1.84

0% AMF Over 8.55 23.87 15.31 1.79Mean 8.85 24.40 15.54 1.76

Under 23.47 38.17 14.70 0.634 Well 22.72 37.63 14.91 0.66

10% AMF Over 20.90 37.65 16.74 0.80Mean 22.37 37.82 15.45 0.70

Under 12.69 28.63 15.94 1.265 Well 13.46 28.63 15.17 1.13

0% emulsifier Over 11.81 27.96 16.15 1.37Mean 12.65 28.40 15.75 1.25

aAMF = anhydrous milk fat.

Figure 5—Relative signal intensity as a function of anhy-drous milk fat (AMF) concentration over storage time. Solidmarkers represent signal intensity from the peanut butterregion, open markers from the chocolate region. Squaremarkers represent 0% AMF; circle markers represent 10%AMF. Markers with a dot inside represent 20 °C storagetemperature; markers without a dot represent 30 °C stor-age temperature.

Figure 4—Relative signal intensity as a function of choco-late particle size over storage time. Solid markers repre-sent signal intensity from the peanut butter region, openmarkers from the chocolate region. Square markers rep-resent 45 �m particle size; circle markers represent 60�m particle size. Markers with a dot inside represent 20°C storage temperature; markers without a dot represent30 °C storage temperature.

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Oil migration in chocolate . . .

of liquid fat over the storage time frame (Sf – S1), and fractionalchange of the liquid fat signal relative to the signal intensity at day1, (Sf – S1)/S1. The signal intensity at day 1 (S1) was the sum of thesignal intensity after 24 h at storage temperature. This value wasviewed to be more indicative of changes at a constant temperaturethan the initial value at day 0 after sample preparation.

For Experimental Design 1, the levels of the factors were as fol-lows: 2 levels of particle size: 45 �m, 60 �m; 3 levels of temper:under-, well-, over-tempered; and 2 storage temperatures: 20 °Cand 30 °C. Results of ANOVA are given in Table 4. Temperaturewas a significant factor for all 3 responses. Increasing the temper-ature from 20 °C to 30 °C increased the rate of migration and theextent of migration. Increasing the particle size from 45 �m to60 �m increased the rate of migration. The amount of migrationwas not statistically different. The degree of temper was not a sig-nificant factor; interaction terms were not significant. The statis-tical analysis indicates that the more porous structure due to thelarger particle size facilitates more rapid oil migration but doesnot significantly affect the amount that migrates.

For Experimental Design 2, the levels of the factors were as fol-lows: 3 levels of anhydrous milk fat: 0%, 3.57%, 10%; 3 levels oftemper: under-, well-, over-tempered; and 2 storage tempera-tures: 20 °C and 30 °C. Like Experimental Design 1, temperaturewas a significant factor for all 3 responses. Increasing the temper-ature from 20 °C to 30 °C increased the rate of migration and theextent of migration. The fractional change in signal was a moresensitive indicator of overall change in signal intensity than thedifference between Sf and S1. Again, the degree of temper was nota significant factor. Similar to Experimental Design 1, interactionterms between the factors were not significant except for temper-ature/AMF for the fractional change. In this case, the signal inten-sity at day 1 was also samples each). The responses over 15 wkwere evaluated, and the ANOVA results are presented in Table 5.The only difference between Table 5 and Table 4 is that the ratesof oil migration are significantly different at P = 0.06 rather thanat � = 0.05. As with the 1st set of experimental designs, particlesizes of 45 �m and 60 �m did not yield significantly different ex-tents of migration; AMF content yielded statistically different rates

and extents of oil migration in the range of 0% to 10%, and emul-sifier levels (at 0% and 0.3%) did not yield significantly differentresponse values for either the rate or extent of migration.

Conclusions

This study identified statistically significant factors impactingoil migration in a model chocolate confectionery system. Based

on the ANOVA results, the most significant factor was storage tem-perature, with particle size and milk fat content statistically signif-

Figure 6—Relative signal intensity as a function of emulsi-fier concentration over storage time. Solid markers rep-resent signal intensity from the peanut butter region, openmarkers from the chocolate region. Square markers rep-resent 0% emulsifier; circle markers represent 0.3% emul-sifier. Markers with a dot inside represent 20 °C storagetemperature; markers without a dot represent 30 °C stor-age temperature.

Figure 7—Relative signal intensity changes in the chocolateregion of different (a) particle size, (b) anhydrous milk fat(AMF) content, and (c) emulsifier concentration samples withdifferent degree of temper at 30 °C. Open markers repre-sent the low level of the factor; closed markers representthe high level of the factor. The square markers are under-tempered chocolate; triangle markers are well-temperedchocolate; and circle markers are over-tempered chocolate.

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AcknowledgmentsThe authors are grateful to Hershey Foods Corp. personnel for pro-viding samples and lending instruments, special thanks to W.Hanselmann, D. Sweigart, J. Furjanic, J. Shuleva, J. Zhao, and D.Teets for insightful discussions. This work was supported by USDAgrant 2002-35503-12276.

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Table 4—Analysis of Variance (ANOVA) for the responsesfrom each experimental designa

FractionalAmt change change

Rate Sf – S1 (Sf –S1)/S1

Experimental Design 1, Formulations: 1, 2Particle size S NS NSDegree of temper NS NS NSTemperature S S SParticle size-temper NS NS NSParticle size-temperature NS NS NSTemper-temperature NS NS NS

Experimental Design 2, Formulations: 1, 3, 4AMFb S NS SDegree of temper NS NS NSTemperature S S SAMF-temper NS NS NSAMF-temperature NS NS STemper-temperature NS NS NS

Experimental Design 3, Formulations: 1, 5Emulsifier NS NS NSDegree of temper NS NS NSTemperature S S SEmulsifier-temper NS NS NSEmulsifier-temperature NS NS NSTemper-temperature NS NS NSaSignificance at the � = 0.05 (P � 0.05) level is designated as “S,” nonsignificance as “NS.”bAMF = anhydrous milk fat.

Table 5—Analysis of variance (ANOVA) for the rate andextent of oil migration into the chocolate region of well-tempered samples stored at 30 °Ca

Rate Extent (Sf – S1)/S1

Particle size, Formulations: 1, 245 �m NSc

NS60 �m S at P = 0.06

AMFb, Formulations: 1, 3, 40%3.57% S S10%

Emulsifier, Formulations: 1, 50% NS NS0.3%aTwo samples at each formulation were tested. Significance at � = 0.05 (P � 0.05)is designated as “S,” non significance as “NS.”bAMF = anhydrous milk fat.cDifferent than Table 4.

icant as well. These factors influenced oil migration rate and theamount of change in liquid oil content in the chocolate over time.Spatial variations in liquid lipid signal were observed that were con-sistent with the observation of Walter and Cornillon (2002) for theirsample of commercial peanut butter and dark chocolate. These spa-tial variations are not completely consistent with Fickian diffusionand suggest that capillary flow may have a role. Most notably, theproton density of liquid fat decreases dramatically at the interfacebetween the peanut butter paste and the chocolate. A “diluting” ef-fect due to the liquid peanut oil (no eutectic) was expected, butimages indicate more complex phenomena than Fickian diffusion.

Table 3—Results of linear regression for the rate of migra-tion for the well-tempered samplesa

Samples at 20 °C Samples at 30 °C

Slope Intercept R2 Slope Intercept R2

Particle size45 �m 0.30 9.19 0.899 5.63 9.91 0.98860 �m 0.40 7.34 0.719 6.93 9.25 0.958

AMF0% 0.15 3.67 0.655 5.75 2.96 0.9983.57% 0.30 9.19 0.899 5.63 9.91 0.98810% 0.51 13.80 0.684 7.08 15.22 0.962

Emulsifier0% 0.28 8.31 0.733 5.69 7.46 0.9780.3% 0.30 9.19 0.899 5.63 9.91 0.990aAMF = anhydrous milk fat.