microencapsulation of green tea extracts and its effects...

International Journal of Basic & Applied Sciences IJBAS-IJENS Vol:16 No:02 16

165902-7373- IJBAS-IJENS @ April 2016 IJENS I J E N S

Microencapsulation of Green tea Extracts and its

Effects on the Physico-Chemical and Functional

Properties of Mango Drinks

Zokti James, A1. Badlishah Sham Baharin

1*, Abdulkarim S. M.

2, Faridah Abas

2,

1Department of Food Technology,

2 Department of Food Science, Faculty of food Science and technology, University Putra, Malaysia

UPM Serdang 43400 Selangor Malaysia

1 Zokti James, A ([email protected]).

2* Badlishah Sham Baharin ([email protected])

3 Abdulkarim S. M. ([email protected])

4 Faridah Abas ([email protected]

Abstract-- Green tea polyphenols have been reported to possess

many biological properties. Inspite of the many potential benefits

of green tea extracts, their sensitivity to high temperature, pH

and oxygen is a major disadvantage towards its effective

utilization in the food industry. Green tea leaves from Cameron

highlands Malaysia were extracted using SFE. To improve the

stability, the green tea extracts was encapsulated by spray-drying

using different carrier materials including maltodextrin (MD),

gum arabic (GA) and chitosan (CTS) and their combination at

different ratios. Encapsulation efficiency, total phenolic content

and antioxidant capacity were determined and were found to be

in the range of 71.41 - 88.04%, 19.32 - 24.90 (g100GAE), and 29.

52 -38.05% respectively. Further analysis of moisture content,

water activity, hygroscopicity and bulk density of the

microparticles were carried out and the results ranged from;

2.31 – 5.11%, 0.28 – 0.36, 3.22 – 4.71% and 0.22 – 0.28g/cm3,

respectively. The ability of the microparticles to swell in SGF and

SIF was determined at 142.00 -188.63% and 207.55 -231.77%

respectively. The microparticles with the best catechin efficiency,

total phenolic content and antioxidant activity were selected and

incorporated into mango drink and its effects on the

physicochemical and functional properties of the product

evaluated during storage. The pH, total solid and viscosity of the

catechin microparticles supplemented range from 5.15 – 4.38,

12.70 – 14.20%, and 12.55 -13.99(cps) respectively. The stability

of green tea bioactives in the mango drink showed degradation

rate in the range of 16.47 – 29.72% compared to the non-

encapsulated powder (46.46%). The green tea extracts

microparticles show good degree of stability in the mango drink

and the antioxidant capacity of the mango drink was significantly

( p ≥ 0.05) different compared to the non-encapsulated powder

at the end of the storage period.

Index Term-- Green tea catechins; Microencapsulation,

Functional food; Mango drink; Stability

1.0. INTRODUCTION

Tea is an infusion of Camellia sinensis only second to water in

term of consumption globally. Green tea is a product from

non-fermented tea leaves as compared to black or oolong teas.

Epidemiological data have shown that consumption of tea has

an inverse relation with reduced risk of certain chronic and

degenerative diseases including certain forms of cancers,

cardiovascular diseases, diabetes, obesity, Alzheimer disease,

weight loss etc. (Basu & Lucas, 2007; Khan & Mukhtar,

2007). The major constituents of green tea catechin

polyphenols include catechin (C), epicatechin (EC),

epigallocatechin (EGC), epigallocatechin gallate (EGCGC),

epicatechin gallate (ECG) and gallic acid. Tea has been listed

among functional foods because of the health promoting

characteristics. Functional foods plays the role of prevention

because of the ability to reduce those factors that compromise

good health (Shibamoto, Kanazawa, & Shahidi, 2008).Green

tea catechin has been incorporated into various foods

including, bread, cakes biscuits, yoghurts , meat pastries etc.

(Anandharamakrishnan, 2014; Yilmaz, 2006). However, green

tea catechins polyphenols have been reported to be susceptible

to degradation/ epimerization at certain temperature and pH of

the environment which reduce the efficacy of the polyphenols

(Lun, Kwok, Huang, & Chen, 2003; Peters, Green, Janle, &

Ferruzzi, 2010). Green tea polyphenols are astringent, bitter

and acrid in taste which sometimes poses problem of

acceptability by the consumer (Narukawa et al., 2011). The

therapeutic value of green tea presents an opportunity to

positively affect the outcome of risk of disease globally.

However, reports showed that the daily consumption of tea

beverage and bioavailability of native catechin monomers is

less than 2% (Henning et al., 2004; Henning, choo, 2008).

Effective administration of tea catechin polyphenols in the

body may require the use of appropriate vehicles to achieve

the required dose. Moreover, it is not certain if individual can

consume sufficient quantity of tea infusion that will provide

the anticipated health benefits in the conventional traditional

beverage. It is reported that a health conscious consumer may

need to drink 10 cups (2000mL) of green tea in Japan to

maintain good health. If 200mL contains 100mg of tea

catechin, therefore 10 cups of tea is equivalent to 1g of tea

catechins (Hara, 2011). If we then go by the Japanese

recommendation the volumes of tea drinks appears too much.

The burdens of consumption of high water can be reduced by

simply turning the liquid into powder and then incorporate

into other foods which appear to be the current trend in the

food industry.

Microencapsulation technology has been used as a successful

delivery tool in the pharmaceutical and food industries to

protect and deliver heath ingredients to the consumers

(Gouin, 2004; Taylor, Mozafari, Khosravi-darani, & Borazan,

2008). Microencapsulation has enable formulators of

functional food ingredients to protect the stability and bring

sustained release of polyphenols ( Lee, Ganesan, & Kwak,

2013; Lee et al., 2013; Oliveira, Santana, & Ré, 2006; Tang et

al., 2013).

mailto:[email protected]






Spray drying is an established technique that has been used for

microencapsulation of bioactive compounds (Gharsallaoui,

Roudaut, Chambin, Voilley, & Saurel, 2007) Spray drying has

been exploited by food industries because of the following

advantages: It is viewed as an already established technology,

has the ability to produce large amount of micocapsules, there

exists many approved shell materials for use or application,

can produce particles sizes of different variety, and is use for

food ingredients that are heat sensitive(Gharsallaoui et al.,

2007; Sansone et al., 2011).

Maltodextrin is one of the wall materials that is commonly use

in the industry for encapsulation of functional food ingredients

because of its unique characteristics (Cai, Luo, Sun, & Corke,

2004; “Gustavo , Barbosa- Canovas, Enrique Ortega-Rivas,

Pablo Juliano and, Hong Yan (2005).

Gum Arabic is a coating material derived from two species of

Acacia tree, Acacia sayel and Acacia Senegal. Gum Arabic is

primarily used as a stabilizer in food industry. It is a good

emulsifier with film forming properties and low viscosity in

aqueous solution which help spray-drying (Krishnan,

Kshirsagar, & Singhal, 2005; Wandrey, Bartkowiak, &

Harding, 2010). Gum arabic is edible completely and

resistance to a number of physicochemical conditions such as

acidic conditions when compared to others which is why is

good for microencapsulation green tea beverage being more

stable in acidic condition (de Vos, Faas, Spasojevic, &

Sikkema, 2010). Chitosan is a non- toxic biopolymer that is

biodegradable and biocompatible with many potentials for

use in biotechnological applications. Because of the cationic

and reactive functional groups chitosan is used in controlled

released formulation in pharmaceutical industries (Dudhani &

Kosaraju, 2010; Zhang & Kosaraju, 2007). Chitosan has

proved to be valuable in wine and juice industry. Recently

polyphenolic extracts from olive leaf was encapsulated by

spry drying using chitosan coating with high loading

efficiency compared to particle made from extrusion (Dudhani

& Kosaraju, 2010; Kosaraju, D’ath, & Lawrence, 2006). In

this study catechin is expected to serve as the main health

promoting agent, however, because chitosan has shown some

beneficial health properties its inclusion as a carrier material

will be of relevance. Encapsulation of catechin extracts using

maltodextrin and gum Arabic along with chitosan is a novel

approach.

One of the approaches to increase the bioavailability of

catechin it to administer tea in combination with fruit juices

(Ferruzzi, 2010; Henning et al., 2004, 2005; Henning SM,

choo JJ et al., 2008). Mango is one of the most popular

tropical fruit commonly called ‘king of fruits’ especially in

Asia. Very many high quality mango clones are found in

Malaysia. A major portion of mango is consumed as fresh

fruit locally. Mango possesses high nutritional potential

because of the relatively high β- carotene contents (pro-

vitamin V) and vitamin C apart from other antioxidant

compounds (Ribeiro, Barbosa, Queiroz, Knödler, & Schieber,

2008).

Malaysia is blessed with variety of fruit and herbs including

tea (Arifullah, Vikram, Chiruvella, Shaik, & Abdullah Ripain,

2014). An attempt has been made to incorporate a Malaysian

local herb- mascotek (Ficusdeltoidea); known to possess high

antioxidant properties into mango drink in order to create

different way of enjoying the freshness and goodness of

mango ([email protected], 2014). One of the

objectives of this study is to produce an enriched mango drink

by incorporating encapsulated green tea extract powder into

mango drink and to evaluate the stability of the catechin

compounds during storage. Tea is produced in Malaysia;

therefore the outcome of this study will serve as an incentive

to tea producers and consumers of tea in Malaysia.

2.0 MATERIAL AND METHODS

2.1. Materials

Fresh tea leaves were obtained from Cameron highlands

Malaysia. Mango drink was purchased from the pilot

processing plant at the faculty of food Science University

Putra Malaysia. Maltodextrin (DE 10- 16), gum arabic,

chitosan were purchased from Scinfield chemicals (Malaysia),

and other chemicals were of analytical grade.

2.2. Microencapsulation of green tea

Green tea extracts was obtained through supercritical carbon

dioxide extraction following the method of Ghoreishi &

Heidari, (2013).

2.3. Preparation of Carbohydrate microcapsules

To find an appropriate formulation for wall material for the

encapsulation of green tea extracts obtained from the

supercritical fluid technique, a simplex centroid mixture of

experimental design based on previous studies (Vaidya,

Bhosale, & Singhal, 2006) was used. A blend of 40g (20%

w/v), commercial maltodextrin (MD), gum Arabic (GA) and

chitosan (CTS) were dispersed in distilled in water. Individual

wall materials were dissolved individually at (60-40oC) with

constant magnetic stirring for 30 minutes to give a final

volumes of 200ml with a total solid of between 18 -21 (oBrix).

Chitosan was separately dissolved in 5% acetic acid before

adding under magnetic stirrer and mixed properly. Two grams

(5% based on wall material used) of supercritical fluid extract

powder of green tea was added to the mixture. The mixture

was homogenized using a mini homogenizer (Model type-SP-

8 Malaysia) for 5minutes at 8000-9500 rpm until complete

dispersion was achieved. The slurry of the water, carrier

material and catechin extracts was spray dried in Buchi, 290

mini sprays dryer (Buchi- Switzerland) equipped with 0.7mm

diameter nozzle at an outlet temperature of 150±5oC, the inlet

temperature was determined by the outlet temperature. The

feed flow rate was 15ml/min. The microparticles prepared

were collected using the glass collecting chamber. The

microparticles powder were filled in aluminium pouches

immediately, sealed and kept in desiccator to cool and to

prevent absorption of moisture until further studies.




2.4. HPLC analysis of catechins

The five major catechin phenolic compounds present in green

tea were analysed by HPLC using the method of Institute

for Nutraceutical Advancement for determination of total

catechins and gallic acids in green tea (INA Method 111.002)

as used by (Perati, Borba, Mohindra, & Rohrer, 2011) with

minor modifications was followed., A reversed-phase C18

column (MetaChem PolarisTM

Amide C18, 5µm, 4.6x250mm);

UV-Vis diode array detector, and a binary solvent system

containing acidified water( 0.1% orthophosphoric acid -

solvent A) and a polar organic solvent ( acetonitrile -solvent

B). Optimized gradient elution order was programmed as

follows: 0 min 96% A: 4% B; 12 min 85% A: 15% B; 22 min

75% A: 25% B; 24 min 85% A: 15% B; 30 min 85% A: 15%

B and 35 min 96% A: 4% B. The flow rate and injection

volume were set at 1mL/min and 10µL respectively with a

post run of 5minutes.The column temperature was 35% while

the wave length was at 280nm using UV detectors. Five stock

solutions of the various catechin standards were prepared by

dissolving 1mg of the individual standards catechins in 1.0mL

solvent to form a 1000 parts per million (ppm) concentrations

and stored in the refrigerator at 40C.

A specified amount of each solution was taken and the 5

aliquots were mixed and diluted to give a wide range of

standard mixtures. The concentration of each catechin in the

green tea extract was determined quantitatively based on the

chromatographic data of the standard mixture. The catechin

components were quantified using the calibration curves of the

standards obtained (Fig.7a).

2.5. Determination Microencapsulation yield

The method of (Robert et al., (2010) with some modification

was adopted for the determination microencapsulation

efficiency..

Total catechin of both surface and entrapped core material was

determined. A 200mg of green tea catechin encapsulated

microparticles was weighed accurately into a test-tube and

2mL of 50:8:42 (v/v/v) of methanol: acetic acid: water was

added. The dispersion was agitated using vortex for 1 min and

ultra-sonicated for 20 min. The supernatant was centrifuged at

9500rpm for 10 min and then filtered using syringe filter

0.45µm. To determine the surface catechin polyphenol 200

mg of the microparticles was treated with a mixture of 2mL

ethanol and methanol (1:1) it was vortexed for 1minutes and

was then filtered using 0.2µm Millipore syringe filters. The

amount of total catechin, TPC and DPPH were quantified. The

surface bioactive compound (SBC) percentage and the

microencapsulation efficiency (ME) of the micro-particles

were calculated according to the equation;

SBC = surface bioactive compounds Theoretical total

bioactive x100 (1)

The microencapsulation efficiency (ME) = 100 – SBC (%)

(2)

2.6. Determination of degree of swelling of microparticles

The methods of Dudhani & Kosaraju, (2010); Oliveira,

Santana, & Re, (2005) with some modification was adopted.

Pre-weight catechin microparticles (200mg) were placed into

a previously soaked visking tubing dialysis bag (2 inf.

Diameter 14.3/ 26 mm pore size 25 angstroms WMCO 1200 –

16000 Dalton, UK) were aseptically placed in to a beaker

containing 150ml simulated gastric and intestinal fluid (pH

2.3 and 7.4 respectively). The content was stirred continuously

at 50rpm and was allowed to swell for 120 minutes during

which the swelling samples were periodically weighed at

interval (0, 20, 40, 60, 80, 100, and 120). The percentage

degree of swelling of the catechin microparticles was

gravimetrically determined using equation below:

Percentage (%) swelling = (Wt – WO) / WO x100

Where Wt represents the weight of swollen sample at the

stipulated time in the simulated fluid and the initial weight of

microparticles before swelling is WO.

2.7. Determination of Physicochemical properties of food

system (mango juice)

The following physicochemical properties of the mango drink

were determined including; pH, total solid, viscosity, TPC,

DPPH and total catechins contents.

To determine the stability of catechin in in mango drink,

various concentrations of the microcapsules (0.5, 1.0, and 2.0

%) containing catechin concentration in the range of 40.65 to

63.42µg/g were added into the mango juice in triplicates and

was mixed properly for 5 minutes at room temperature to

represent day 0. Four batches representing week, 1, 2, 3, and 4

were prepared and was stored at 4oC in a refrigerator. A 1mL

Sample from mixture of catechin microcapsules and mongo

drink was diluted with an equal volume of 70% methanol (v/v)

and was centrifuged at 4500rpm for 10 minutes. The

supernatant was collected using 0.2µm syringe micro-filters

and the amount of catechin released from the microparticles

was analysed for TPC, DPPH and total catechin (TC) using

UV- Vis spectrophometer and HPLC methods respectively.

All samples were prepared in triplicates.

2.7.1 Determination of pH

The pH of the juice both blank and the one that catechin

microparticles powder has been added was determined by pH

meter (pH 700 EU TECH, Instruments) at 7days intervals for

thirty days.



2.7.2 Determination of Viscosity

Measurement of viscosity were done using a rheometer (

physical – Rheolab) with spindle No. 2 at 1550 s-1

shear rate

over a period of 1200 second at temperature of between 23-

250C and the viscosity means was recorded over the period.

All samples were measured in triplicates.

2.7.3. Determination of soluble solids (oBrix) of feed

A digital handheld refractometer (32 Atago Co, Ltd Tokyo

Japan) was used to determine the soluble solids (%). The

refractometer was cleaned properly and calibrated using

deionized distilled water (0 oBrix) before measurement was

carried out. To measure the soluble solids oBrix a drop of

mango was added to the refractometer at room temperature

(24oC) before taking the reading. Measurement was carried in

triplicate.

2.7.4 Determination of total phenolics compounds (TPC)

The amount of total phenol in the microparticles was

estimated colorimetrically following the methods used by

International Organization for standardization ISO14502-

1(2005) and Robert et al., (2010) adopted.

2.7.5. Antioxidant activity determination

Antioxidant activity was determined by the catechins capacity

to scavenge stable DPPH radicals following the method of

(Rutz et al., 2013) with slight modification. Briefly, 1mL of

mango drink was extracted using ethanol (70% v/v), 100µLof

the supernatant was added to 3.9mL of ethanolic solution of

0.1 mM DPPH. The mixture was incubated at room

temperature (25oC) in the dark for 30 minutes. Sample

absorbance (AS sample) was measured using

spectrophotometer (Thermo Fisher Scientific-GENESY 10S

UV.VIS, Malaysia) at 517nm against absorbance of ethanol

blank (AB). Samples were determined in triplicate. The

radical scavenging activity was calculated using the formula:

% Inhibition = [(AB – AS /AB)] x 100.

Where: AB is absorbance of blank; AS is the absorbance of the

sample of green tea catechin microparticles.

2.7.6. Formulation of green tea catechin/ mango juice

Drink system

Bottled mango drink packaged in 100mL volumes prepared by

the Department of Food technology, Faculty of food science

and Technology University Putra for commercial purpose

were obtained in June, 2015. The drink was prepared by

diluting the concentrate to a ratio of 1:3 concentrate to water.

The formulated drink contains the following per 100ml:

energy -33kcal, carbohydrate -8.1g, protein -0.1g, fat-0.0g,

total sugar- 8.0g, vitamin C -1.1mg, and fibre -0.1g. Batches

of supplemented mango drink samples were prepared by

incorporating powdered green tea microparticles into a pre-

weighed mango drinks before storage at 4oC for 4weeks.

3.0. RESULTS AND DISCUSSION

3.1. Microencapsulation Efficiency (ME)

Microencapsulation efficiency is carried with the sole aim to

determine the loss of core material before, during and after

processing microparticles. It is the percentage of entrapped

catechin over the total catechin in the system. The efficiency

microencapsulation and total catechin compounds are

presented in Figure1 and Table3.1. The encapsulation

efficiency of the total catechin as well as the summary of TPC

and DPPH scavenging activity of the spray dried

microparticles. The encapsulation efficiency was in the range

of 71.41 -88.04%, whereas the total catechin contents was in

the range of 7046.70 -8687.90mg/100g. The formulation with

100 per cent gum Arabic produced microparticles with highest

encapsulation efficiency (88.04%). The results of total

phenolic compounds and antioxidant capacity are presented in

Fig.2 and 3. The total phenolic compounds of the

microparticles were in the range of 24.90 -19.32 g/100gGAE

whereas the antioxidant capacity was in the range 29.52 -

38...05 -71.99%. However, the formulation with 25:74:1

(maltodextrin: gum arabic: chitosan) gave the lowest catechin

microparticles encapsulation efficiency (71.99%) but

produced the highest total polyphenolic compounds (24.74g/

100g GAE) and DPPH activity of 38.05% respectively. This

can be attributed to the combined antioxidant effects of gum

arabic, chitosan and green tea catechin. Antoxidative effect of

chitosan has been reported (Dudhani & Kosaraju, 2010;

Muzzarelli, n.d.; Shahidi,Arachi, 1999). Encapsulation

efficiency can be affected by the nature of wall materials and

the that will in turn influences the antioxidant activity

(Ezhilarasi, Indrani, Jena, & Anandharamakrishnan, 2013).

The physicochemical properties of the spry dried

microparticles were evaluated shown in (Table3.2). The

moisture content, water activity, degree of hygroscopicity,

bulk density, and tap density were in the range of 2.31-4.78%,

0.36-0.28, 3.22 -4.94%, 0.20 -0.28g/cm3 and 0.25g/cm

3

respectively. These properties showed that the powders were

of better quality characteristics (Şahin Nadeem, Torun, &

Özdemir, 2011). Table 3.3 shows the five major catechin

compounds that were isolated by HPLC in the spray dried

green tea microparticles. The major catechin compounds

associated with antioxidant properties of catechin are C, EC,

EGC, EGCG, GCG and ECG. The results showed significant

(p ≤ 0.05) variation among elements within a column. The

result of the percentage individual catechin compounds

isolated in this study reflects previous studies by other

researchers on similar subject (Vuong, Golding, Nguyen, &

Roach, 2013; Vuong, Q.v., Nguyen, V., Golding J.B., Roach,



Vuong, Golding, Nguyen, & Roach, 2010). Similarly, the

results of the antioxidant properties of green tea catechin

obtained after microencapsulation was also comparable to

similar works reported by other researchers (Bakowska-

Barczak & Kolodziejczyk, 2011; Peres et al., 2011). This

study supports the assertion that the antioxidant properties and

the efficacy of green tea catechins is attributed to the presence

catechin epimers and that encapsulation by spray drying using

carbohydrate polymers as carriers can be used to retain the

important catechin epimers after spray drying and storage.

Previous reports indicated good encapsulation efficiency of

catechin compounds when maltodextrins and gum arabic were

used as carrier materials for spray drying phenolic compounds

(Davidov-pardo & Arozarena, 2013; Taylor, Vaidya, Bhosale,

& Singhal, 2007; Zhang & Kosaraju, 2007).The low retention

of catechin added chitosan in this study could be a result of

emulsifying capacity in the feed solution and the interaction

that might have taken place between the core materials and

chitosan (Dudhani & Kosaraju, 2010; B. F. Oliveira et al.,

2006).Although the intention of this work was to use catechin

antioxidant as the main therapeutic material, because chitosan

has been reported to have health beneficial affects it very

possible that utilizing chitosan to deliver catechin may be of

added health benefits to the consumer. This justifies the

relevance considering chitosan-based food delivery system.

3.2. Swelling studies of microparticles

It was anticipated that the release of microparticles may occur

by swelling and degradation. Since the particles were prepared

as food ingredient, release of catechin was characterized in

condition mimicking digestion in both the gastric (pH 2.3) and

intestinal (pH7.4) conditions. The microparticles of green tea

from the formulated wall materials demonstrated swelling of

142.00 – 188.65% over a period of 120 minutes in the SGF (

Fig.3.4a&b); whereas the swelling index in simulated

intestinal (SIF) was in the range 207.55 -231.77%

(Fig.3.5a&b). There was a significant difference (p ˂ 0.05) in

swelling index of microcapsules containing chitosan on SGF

and SIF when compare to others without chitosan blend.

Swelling of microparticles containing high ratio of

maltodextrin reached equilibrium within the first 40 minutes,

whereas blends of maltodextrin /gum arabic / chitosan reached

swelling equilibrium within 60- 100 minutes. The pH of the

medium played a significant (P ˂ 0.05) role in the swelling

capacity of catechin loaded microparticles. All the

microparticles swell less in the SGF except those containing

chitosan blends compared to those incubated in SIF

conditions. There are very limited reports on pH dependent

swelling index and stability of catechin microparticles in

related studies(Dudhani & Kosaraju, 2010). Reports on insulin

pH dependent swelling and chitosan nanoparticles shows that

chitosan swells more in the gastric pH, compared to the

intestinal pH (Dudhani & Kosaraju, 2010, Shu &Zhu,2002).

In this study the swelling pattern of the microparticles can be

attributed to the high swelling of chitosan and its ability to

uncoil the carbohydrate molecules to an extended structure

with higher molecular weight because of the pH controlled

electrostatic interaction between anions and chitosan film

Agarwal, V., & Mishra, (1999) reported similar behaviour in

chitosan containing spray dried particles. Although there are

few on pH motivated swellings, higher swelling in the case

of chitosan blend microparticles may be attributed protonation

of the amino group of chitosan when pH decreases ( Oliveira,

Santana, & Ré, 2006). The degree of swelling observed may

have been caused by factors such particles size and catechin

wall materials interaction.

3.3. Physicochemical analysis of mango drink

3.3.1. Effects of storage on pH, total solid (oBrix) and

viscosity

Fig3.6a shows the mean values of changes in pH of mango

/catechin supplemented drink stored at 4±1oC for 30 days. It

was observed that when the concentration of catechin

microcapsules increased from 0.5 to 2.0% the pH value of

the drink increased from 5.15 to 5.17 except in the case of

free (non-encapsulated) green tea extract where the pH

decreased significantly ( p ≤ 0.05) to 5.09. However, it was

generally observed that there was a reduction in the pH values

(5.15 to 5. 12) at day - 0 depending on the carrier materials.

In this study it was observed that as the storage period

increases the pH values decreases generally so that by the

third week storage period there was no significant ( p ≤

0.05) difference among the groups including the control

sample. Except for the free (non-encapsulated) green tea

extract which shows lower pH at the end of the storage period.

It has been reported that the normal pH range of mango fruit

drink is in the range 4.5 -5.0 (Vasquez- Calcedo et al.; (2002).

It was observed that as the period of storage increased

irrespective of the concentration of the microparticles the pH

values decreases significantly (p ≤ 0.05) for both the control

and test samples. However, pH value of the control samples

and that of free showed significantly (p ≤ 0.05) difference

from that catechin microcapsules incorporated samples. The

pH of the supplemented mango drink was generally within the

normal range after the storage period. The addition of catechin

microcapsules in the mango drink did significantly affect the

pH of the mango drink.

3.3.2 Total soluble solid (TS)

The result of the total soluble solid (oBrix) as was monitored

during the storage period at 4oC is shown in Fig3.6b. It was

observed that the value of the total soluble solid (oBrix) did

not show significant (p ≥ 0.05) difference between the control

mango drink and the catechin incorporated mango at 0 day.

However, it was observed that as the concentration of the

incorporated microparticles in the drink increased from 0.5 –

2.0% the value of the oBrix also increased significantly (p ≤

0.05). As the period of incubation increased; the value oBrix

also increased and finally stabilizes at the end of the forth

week. The introduction of the microparticles did not



significantly (p ≤ 0.05) affect the total solid of the mango

drink since value of the oBrix was within the normal range 10-

16% which considered normal (Vasquez- Calcedo et al.;

2002).

3.3.2 Viscosities

The analysis of viscosity is a simple but rapid method by

which we determine the thoroughness of the rate of mixing of

the ingredients. It also enables us to assess how the level of

solids, degree emulsification and hydrolysis can impact the

quality and consistency of the product. When the viscosity is

increases it tends to maintain the stability of the product by

keeping the insoluble ingredients in suspension and preserving

the homogeneity of the solutions (Rossman, 2009).

The viscosity value of the mango drink supplement as

examined during the storage period is presented in Fig3.6c.

The result shows that the viscosity was not significantly (p ≤

0.05) different when the microparticles were introduced

during the first two weeks of the storage period (0, 1 & 2), but

sample without the microparticles (non-encapsulated green

tea extracts and control) were significantly (p ≤ 0.05)

different. At the end of the storage period the viscosity values

increased significantly (p ≤ 0.05) for the entire sample

irrespective of the concentration and composition of the

microparticles.

3.3.4. Effect of time and temperature on the Stability

catechin in mango drink stored for 30 days at 4oC

Fig3.7 a, b &c shows the representative chromatograms of

catechin compounds obtained during HPLC analysis of

mango drink supplemented, Fig.7 (a) represent the

chromatogram of reference standard catechin compounds, (b)

chromatogram of green tea catechin analysis at week 0

storage, and (c) represents the chromatogram of catechins

analysis at the end of storage period (week 4). Fig3.8a, b &c

showed the stability of total catechin present in the

supplemented mango drink isolated by HPLC at different

concentration (0.5, 1.0 and 2.0%, whereas Fig3.9 illustrates

total percentage degradation rate of catechins. The

encapsulated catechin compounds were relatively stable at the

storage temperature (4oC) with degradation rate in the range

16.47 -29.72 %. However, the rate of degradation of catechin

compounds in the free catechin extract powder (control) was

higher than those of the encapsulated powder catechin

(45.26%) at the end of 4 weeks storage. The rate of release of

catechin in the mango drinks matrix increase proportionally

with the concentration of incorporated microparticles (2.0 ˃

1.0 ˃ 0.5). The higher the concentration of the catechin

microparticles the higher the level of catechin released. The

stability of catechin was affected by type of wall materials and

time (Fig3.9).

The effects of temperature, pH and food ingredients on the

stability catechin from green tea extracts have been

extensively studied (Chang, 2006; Friedman, , Levin, C. E.,

Choi, ., Lee, & Kozukue, 2009; Lun Su et al., 2003; ). In the

report ascorbic acid one of the ingredients in mango is

reported to play dual roles as an antioxidant and pro-oxidant

(Hara, 2001; Lun Su et al., 2003). In this study the minimal

degradation in the microencapsulated green tea catechin may

be attributed to the combined effects of low temperature, and

pH. Other ingredients might have also played significant roles.

Previous study on epimerization reaction of EGCG, EGC,

ECG and EC, shows that epimerization will result in

corresponding dimmers like GCG, CG, GC respectively. We

observed that the peak area of GC a corresponding dimer from

EGCG sharply increased at the end of the 4th

week storage

(Fig3.7c). This may have been caused by epimerization

reaction of other corresponding epimers. This finding is in

agreement with that of Chen et al.; (201), who reported

instances where catechin exhibited varying stability went it

was added to commercially sold soft drinks containing sucrose

or ascorbic acid. The high stability of catechins in mango juice

to water as observed in this study may be linked to the

chemical composition of the product.

3.3.5. Determination TPC

The amount of total phenolic content and antioxidant activity

of the supplemented mango drink as monitored during the

storage period of 4 weeks at 4oC is shown in Fig3.10a &b.

The polyphenols in green tea extracts is attributed to

catechins. The release rate of TPC and antioxidant was

proportional to increase in concentration of microparticles

incorporated (0.5, 1.0 and 2.0% w/v.) The TPC of the control

sample decreased by 20.0% against the TPC of the catechin

supplemented mango drink (3.01 -6.66%) [Fig3.10a]. There

was no significant (p ≤ 0.05) difference in the total phenolic

content mong the catechin microcapsules incorporated into the

supplemented mango drinks except for MD: GA: CTS

(25:74:1) which decreased by as much as 6.66%. This may

be attributed to synergy between catechins / mango drink

matrix, ingredients and other factors inherent in the mango

drink (Madhujith & Shahidi, 2006, Becker et al.; 2004).

Fig.3.10.b showed the evaluation of the DPPH radical

scavenging activity of the mango drink supplemented with

catechin microparticles stored at 4oC for 4 weeks. The

percentage stability of the radical scavenging activity was

between 79.92 - 96.17% thus less than 25% degradation rate.

The free catechin extracts (control) powder exhibited less

antioxidant activity compared to the encapsulated catechin

powder at the storage temperature. It has been reported that

the antioxidant properties of foods correlate with the presence

of selected compounds within the food system (Ramadan,

Sharanabasappa, Seetharam, Seshagiri, & Moersel, 2006). We

can infer that the antioxidant properties of the mango drinks

evaluated is a reflection of different endogenous antioxidant

and that of the green tea catechins which contributed to the

radical quenching activity or efficiency of the mango drink.

On the whole, the result of this study agrees with those found

in the literature on green tea antioxidant activities.



CONCLUSION

At the end of this study we found out that encapsulated

supercritical fluid (Camellia sinensis) green tea catechin

extracts microparticles could be a suitable phenolic compound

for adding into mango drink. The encapsulated catechin

compounds were more stable in the supplemented mango

drinks in comparison with the non-encapsulated catechin

powder with improved functionality. The catechin extracts

did not affect the physicochemical properties of the mango

drink in terms of pH, total solid (oBrix), and viscosity of the

drinks. Among the four most important catechin monomers

EGCG and EGC showed higher degradation rate than EC and

ECG. This may be attributed to the high antioxidant

potentials due to the number of hydroxyl groups. Therefore

this study suggests that catechin microcapsules have the

potential to be used as a functional food ingredient for heath

drink.

ACKNOWLEDGEMENT

The authors will like to thank The University Putra Malaysia

for the financial support for the faculty of Food Science and

Technology. We are so grateful to Associate prof. Dr.

Badlishah S.B., who secure the grant secured the grant for the

research.

REFERENCE [1] Agarwal, V., & Mishra, B. (1999). Design, development, and

biopharmaceutical properties of buccoadhesive compacts of

pentazocine. Drug Development and Industrial Pharmacy, 25(6),

701–709. [2] Anandharamakrishnan, C. (2014). Techniques for

Nanoencapsulation of Food Ingredients (Vol. 1). New York, NY:

Springer New York. http://doi.org/10.1007/978-1-4614-9387-7 [3] Arifullah, M., Vikram, P., Chiruvella, K. K., Shaik, M. M., &

Abdullah Ripain, I. H. (2014). A Review on Malaysian Plants

Used for Screening of Antimicrobial Activity. Annual Research & Review in Biology, 4(13), 2088–2132.

[4] Bakowska-Barczak, A. M., & Kolodziejczyk, P. P. (2011). Black

currant polyphenols: Their storage stability and microencapsulation. Industrial Crops and Products, 34(2), 1301–

1309. http://doi.org/10.1016/j.indcrop.2010.10.002

[5] Basu, A., & Lucas, E. a. (2007). Mechanisms and effects of green tea on cardiovascular health. Nutrition Reviews, 65(8 Pt 1), 361–

75. Retrieved from

http://www.ncbi.nlm.nih.gov/pubmed/17867370 [6] Cai, Y., Luo, Q., Sun, M., & Corke, H. (2004). Antioxidant

activity and phenolic compounds of 112 traditional Chinese

medicinal plants associated with anticancer. Life Sciences, 74(17), 2157–84. http://doi.org/10.1016/j.lfs.2003.09.047

[7] Chang, Q. (2006). Food Chemistry Effect of storage temperature

on phenolics stability in hawthorn ( Crataegus pinnatifida var . major ) fruits and a hawthorn drink, 98, 426–430.

http://doi.org/10.1016/j.foodchem.2005.06.015

[8] Davidov-pardo, G., & Arozarena, I. (2013). Optimization of a

Wall Material Formulation to Microencapsulate a Grape Seed

Extract Using a Mixture Design of Experiments, 941–951.

http://doi.org/10.1007/s11947-012-0848-z [9] de Vos, P., Faas, M. M., Spasojevic, M., & Sikkema, J. (2010).

Encapsulation for preservation of functionality and targeted

delivery of bioactive food components. International Dairy Journal, 20(4), 292–302.

http://doi.org/10.1016/j.idairyj.2009.11.008

[10] Dudhani, A. R., & Kosaraju, S. L. (2010). Bioadhesive chitosan nanoparticles: Preparation and characterization. Carbohydrate

Polymers, 81(2), 243–251.

http://doi.org/10.1016/j.carbpol.2010.02.026 [11] Ezhilarasi, P. N. N., Indrani, D., Jena, B. S. S., &

Anandharamakrishnan, C. (2013). Freeze drying technique for

microencapsulation of Garcinia fruit extract and its effect on bread

quality. Journal of Food Engineering, 117(4), 513–520. http://doi.org/10.1016/j.jfoodeng.2013.01.009

[12] Ferruzzi, M. G. (2010). The influence of beverage composition on

delivery of phenolic compounds from coffee and tea. Physiology & Behavior, 100(1), 33–41.

http://doi.org/10.1016/j.physbeh.2010.01.035

[13] Friedman, M., Levin, C. E., Choi, S. H., Lee, S. U., & Kozukue, N. (2009). Changes in the composition of raw tea leaves from the

Korean Yabukida plant during high temperature processing to pan-

fried Kamairi-Cha green tea. Journal of Food Science, 74, C406 –C412.

[14] Gharsallaoui, A., Roudaut, G., Chambin, O., Voilley, A., & Saurel,

R. (2007). Applications of spray-drying in microencapsulation of food ingredients: An overview. Food Research International,

40(9), 1107–1121. http://doi.org/10.1016/j.foodres.2007.07.004

[15] Ghoreishi, S. M. M., & Heidari, E. (2013). Extraction of Epigallocatechin-3-gallate from green tea via supercritical fluid

technology: Neural network modeling and response surface

optimization. The Journal of Supercritical Fluids, 74, 128–136. http://doi.org/10.1016/j.supflu.2012.12.009

[16] Gouin, S. (2004). Microencapsulation. Trends in Food Science &

Technology, 15(7-8), 330–347. http://doi.org/10.1016/j.tifs.2003.10.005

[17] Gustavo , v. Barbosa- Canovas, Enrique Ortega-Rivas, Pablo

Juliano and, Hong Yan (2005). Powders: Physical properties, processing, and functionality. Kluwer Academic/ Plenum

publishers. New York. 19-27. 52. (2005), 2005. [18] Hara, Y. (2001). Green tea- health benefits and Applications. New

York, NY: Marcel dekker, Inc.

[19] Hara, Y. (2011). Tea catechins and their applications as supplements and pharmaceutics. Pharmacological Research : The

Official Journal of the Italian Pharmacological Society, 64(2),

100–4. http://doi.org/10.1016/j.phrs.2011.03.018 [20] Henning, S. M., Niu, Y., Lee, N. H., Thames, G. D., Minutti, R.

R., Wang, H., & Go, V. L. W. (2004). Bioavailability and

antioxidant activity of tea flavanols after consumption of green tea , black tea , or a green tea extract, (1), 1558–1564.

[21] Henning, S. M., Niu, Y., Liu, Y., Lee, N. H., Hara, Y., Thames, G.

D., … Heber, D. (2005). Bioavailability and antioxidant effect of epigallocatechin gallate administered in purified form versus as

green tea extract in healthy individuals. The Journal of Nutritional

Biochemistry, 16(10), 610–6. http://doi.org/10.1016/j.jnutbio.2005.03.003

[22] Henning SM, choo JJ, H. D. (2008). Nongallated compared with

gallated flavan-3-ols in green and black tea are more bioavailable. J Nutr, 138, 1529s–34s.

[23] Henning SM, choo JJ, H. D., Susanne, M., Jung, J., Henning, S.

M., Choo, J. J., & Heber, D. (2008). Nongallated compared with gallated flavan-3-ols in green and black tea are more bioavailable.

J Nutr, 138(8), 1529s–34s. Retrieved from

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2942025&tool=pmcentrez&rendertype=abstract

[24] J.M., R. (2009). Edible films and coatings for food applications. In

K. C. Embuscado, M.E., Huber (Ed.), Edible films and coatings for food applications (pp. 367–390). New York, NY: . Springer

Science Business Media, LLc, New York, NY.

[25] Khan, N. . M. H. N., & Mukhtar, H. (2007). Tea polyphenols for

health promotion. Life Sciences, 81(7), 519–33.

http://doi.org/10.1016/j.lfs.2007.06.011

[26] Kosaraju, S. L., D’ath, L., & Lawrence, A. (2006). Preparation and characterisation of chitosan microspheres for antioxidant delivery.

Carbohydrate Polymers, 64(2), 163–167.

http://doi.org/10.1016/j.carbpol.2005.11.027 [27] Krishnan, S., Kshirsagar, A. C., & Singhal, R. S. (2005). The use

of gum arabic and modified starch in the microencapsulation of a

food flavoring agent. Carbohydrate Polymers, 62(4), 309–315. http://doi.org/10.1016/j.carbpol.2005.03.020

[28] Lee, Y. K., Ganesan, P., & Kwak, H. S. (2013). Properties of Milk

Supplemented with Peanut Sprout Extract Microcapsules during Storage. Asian-Australasian Journal of Animal Sciences, 26(8),

1197–1204. http://doi.org/10.5713/ajas.2013.13060



[29] Lee, Y.-K. K., Al Mijan, M., Ganesan, P., Yoo, S., & Kwak, H.-S.

S. (2013). The physicochemical properties of yoghurt supplemented with microencapsulated peanut sprout extract, a

possible functional ingredient. International Journal of Dairy

Technology, 66(3), 417–423. http://doi.org/10.1111/1471-0307.12047

[30] Lun Su, Y., Leung, L. K., Huang, Y., Chen, Z.-Y., Xu.J.Z.;

LEUNG, L.K.;Huang. Y.;Chen, Z. ., Su, Y.L., Leung, L.K., Huang, Y., & Chen, Z. Y., & Su, Y.L., Leung, L.K., Huang, Y.,

Chen, Z. Y. (2003). Stability of tea theaflavins and catechins. Food

Chemistry, 83(2), 189–195. http://doi.org/10.1016/S0308-8146(03)00062-1

[31] Lun, Y., Kwok, L., Huang, Y., & Chen, Z. (2003). Stability of tea

theaflavins and catechins, 83, 189–195. http://doi.org/10.1016/S0308-8146(03)00062-1

[32] Muzzarelli R.A.A. (n.d.). Recent results in the oral administration

of chitosan,. EUCHIS ,Universitaet Potsdam , Potsdam. [33] Narukawa, M., Noga, C., Ueno, Y., Sato, T., Misaka, T., &

Watanabe, T. (2011). Evaluation of the bitterness of green tea

catechins by a cell-based assay with the human bitter taste receptor hTAS2R39. Biochemical and Biophysical Research

Communications, 405(4), 620–5.

http://doi.org/10.1016/j.bbrc.2011.01.079 [34] Oliveira, B. F., Santana, M. H. a, & Re, M. I. (2005). Spray-dried

chitosan microspheres cross-linked with D,L-glyceraldehyde as a

potential drug delivery system: Preparation and characterization. Brazilian Journal of Chemical Engineering, 22(3), 353–360.

[35] Oliveira, B. F., Santana, M. H. a., & Ré, M. I. (2006). Spray-Dried Chitosan Microspheres as a pDNA Carrier. Drying Technology,

24(3), 373–382. http://doi.org/10.1080/07373930600564480

[36] Ortiz, J., Kestur, U. S., Taylor, L. S., & Mauer, L. J. (2009). Interaction of environmental moisture with powdered green tea

formulations: relationship between catechin stability and moisture-

induced phase transformations. Journal of Agircultural and Food Chemistry, 57(11), 4691–7. http://doi.org/10.1021/jf8038583

[37] Perati, P. R., Borba, B. De, Mohindra, D., & Rohrer, J. (2011).

Rapid Determination of Antioxidant Polyphenols in Beverages and Herbal Supplements Antioxidants.

[38] Peres, I., Rocha, S., Gomes, J., Morais, S., Pereira, M. C., &

Coelho, M. (2011). Preservation of catechin antioxidant properties loaded in carbohydrate nanoparticles. Carbohydrate Polymers,

86(1), 147–153. http://doi.org/10.1016/j.carbpol.2011.04.029

[39] Peters, C. M., Green, R. J., Janle, E. M., & Ferruzzi, M. G. (2010). Formulation with ascorbic acid and sucrose modulates catechin

bioavailability from green tea. Food Research International, 43(1),

95–102. http://doi.org/10.1016/j.foodres.2009.08.016 [40] Ramadan, M. F., Sharanabasappa, G., Seetharam, Y. N., Seshagiri,

M., & Moersel, J.-T. (2006). Characterisation of fatty acids and

bioactive compounds of kachnar (Bauhinia purpurea L.) seed oil. Food Chemistry, 98(2), 359–365.

http://doi.org/10.1016/j.foodchem.2005.06.018

[41] Ribeiro, S. M. R., Barbosa, L. C. A., Queiroz, J. H., Knödler, M., & Schieber, A. (2008). Phenolic compounds and antioxidant

capacity of Brazilian mango (Mangifera indica L.) varieties. Food

Chemistry, 110(3), 620–626. http://doi.org/10.1016/j.foodchem.2008.02.067

[42] Robert, P., Gorena, T., Romero, N., Sepulveda, E., Chavez, J., &

Saenz, C. (2010). Encapsulation of polyphenols and anthocyanins

from pomegranate (Punica granatum) by spray drying.

International Journal of Food Science & Technology, 45(7), 1386–

1394. http://doi.org/10.1111/j.1365-2621.2010.02270.x

[43] Rutz, J. K., Zambiazi, R. C., Borges, C. D., Krumreich, F. D.,

Suzane, R., Hartwig, N., & Cleonice, G. (2013). Microencapsulation of purple Brazilian cherry juice in xanthan ,

tara gums and xanthan-tara hydrogel matrixes. Carbohydrate

Polymers, 98(2), 1256–1265. http://doi.org/10.1016/j.carbpol.2013.07.058

[44] Şahin Nadeem, H., Torun, M., & Özdemir, F. (2011). Spray drying

of the mountain tea (Sideritis stricta) water extract by using different hydrocolloid carriers. LWT - Food Science and

Technology, 44(7), 1626–1635.

http://doi.org/10.1016/j.lwt.2011.02.009 [45] Sansone, F., Mencherini, T., Picerno, P., D'Amore, M.,

Aquino, R. P., & Lauro, M. R. (2011). Maltodextrin/pectin

microparticles by spray drying as carrier for nutraceutical extracts. Journal of Food Engineering, 105(3), 468–476.

http://doi.org/10.1016/j.jfoodeng.2011.03.004

[46] Shahidi F. , Arachi J.K., J. Y. J. (1999). Food applications of chitin and chitosan. T Rends Food Sci. Technol, 10, 37 – 51.

http://doi.org/10.1017/CBO9781107415324.004

[47] Shibamoto, T., Kanazawa, K., & Shahidi, F. (2008). Functional Food and Health : An Overview, 1–6.

[48] Tang, D.-W. W., Yu, S.-H. H., Ho, Y.-C. C., Huang, B.-Q. Q.,

Tsai, G.-J. J., Hsieh, H.-Y. Y., … Mi, F.-L. L. (2013). Characterization of tea catechins-loaded nanoparticles prepared

from chitosan and an edible polypeptide. Food Hydrocolloids,

30(1), 33–41. http://doi.org/10.1016/j.foodhyd.2012.04.014 [49] Taylor, P., Mozafari, M. R., Khosravi-darani, K., & Borazan, G.

G. (2008). International Journal of Food Properties Encapsulation of Food Ingredients Using Nanoliposome Technology, (November

2012), 37–41. http://doi.org/10.1080/10942910701648115

[50] Taylor, P., Vaidya, S., Bhosale, R., & Singhal, R. S. (2007). Drying Technology : An International Journal Microencapsulation

of Cinnamon Oleoresin by Spray Drying Using Different Wall

Materials Microencapsulation of Cinnamon Oleoresin by Spray Drying Using Different Wall Materials, (May 2013), 37–41.

http://doi.org/10.1080/07373930600776159

[51] Vaidya, S., Bhosale, R., & Singhal, R. S. (2006). Microencapsulation of Cinnamon Oleoresin by Spray Drying

Using Different Wall Materials. Drying Technology, 24(8), 983–

992. http://doi.org/10.1080/07373930600776159 [52] Vuong, Q. V., Golding, J. B., Nguyen, M. H., & Roach, P. D.

(2013). Preparation of decaffeinated and high caffeine powders

from green tea. Powder Technology, 233, 169–175. http://doi.org/10.1016/j.powtec.2012.09.002

[53] Vuong, Q.v., Nguyen, V., Golding J.B., Roach, P. D., Vuong, Q.

V, Golding, J. B., Nguyen, M., & Roach, P. D. (2010). Extraction and Isolation of catechins from tea. Journal of Seperation Science,

33, 3415–3428. http://doi.org/10.1002/jssc.201000438

[54] Wandrey, C., Bartkowiak, A., & Harding, S. E. (2010). Materials for Encapsulation Gum arabic Scientific Committee on Food.

[55] Yilmaz, Y. (2006). Novel uses of catechins in foods. Trends in

Food Science & Technology, 17(2), 64–71. http://doi.org/10.1016/j.tifs.2005.10.005

[56] Zhang, L., & Kosaraju, S. L. (2007). Biopolymeric delivery system

for controlled release of polyphenolic antioxidants. European Polymer Journal, 43(7), 2956–2966.

http://doi.org/10.1016/j.eurpolymj.2007.04.033



Table3.1. Total polyphenol and catechin of green tea microparticles and their entrapped efficiency

Wall material (%) TPC (g/100gGAE) DPPH (%) TC(mg/100g) Efficiency TC (%)

FREE GTE 28.19±0.30a 43.07±0.83

a 9867.20±63.43

a NA

MD: GA: CTS (25:74:1) 24.90±0.05b 38.05±1.27

b 7046.70±53.11

d 71.41±1.62

g

MD: GA: CTS (0:99:1) 24.74±0.07 b 37.80±0.55

c 7217.85±39.41

cd 73.15±0.57

g

MD: GA: CTS (50:49:1) 24.16±0.09b 36.92±0.57

c 7117.25±52.93

d 72.10±0.22g

MD: GA: CTS (99:0:1) 22.94±0.05c 35.05±0.04

d 7313.57±36.56

bcd 74.12±2.31

g

MD: GA: CTS (75:24:1) 22.88±0.45c 34.96±0.55

d 7722.22±46.72

bcd 78.26±0.42

f

MD: GA: CTS (0:100:0) 21.74±0.07d 33.22±0.39

e 8687.90±51.12

b 88.04±0.08

b

MD: GA: CTS (100:0:0) 21.46±0.04d 32.79±0.12

ef 8042.90±51.29

bcd 81.51±0.15

e

MD: GA: CTS (25:75:0) 21.32±0.04d 32.58±0.43

ef 8404.88±51.75

cd 85.18±1.63

c

MD: GA: CTS (50:50:0) 21.10±0.06d 32.24±0.41

f 8232.20±54.85

d 83.43±0.27

d

MD: GA: CTS (75:25:0) 19.32±0.14e 29.52±0.34

g 8019.09±54.15

c 81.27±0.13

e

Results are mean ± SD of three determinations of catechin microparticles based on 5% carrier materials used. Means values in columns carrying the same superscript letters are not

significantly (p ≤ 0.05) different. NA –not applicable



Table3.2. Physicochemical properties of spray-dried green tea microparticles

Sample particle Moisture (%) Hygroscopicity (%) Water activity(aw) Bulk density(g/cm

3) Tap density(g/cm

3)

MD:GA:CTS(100:0:0)

MD:GA:CTS(0:100:0)

MD:GA:CTS(75:25:0)

MD:GA;CTS(50:50:0)

MD:GA:CTS(25:75:0)

MD:GA:CTS(99:0:1)

MD:GA:CTS(0:99:1)

MD:GA:CTS(75:24:1)

MD:GA:CTS(50:49:1)

MD:GA:CTS(25:74:1)

Crude powder(BLK)

3.16±0.06f

4.58±0.04c

2.49±0.06g

3.36±0.06e

2.31±0.01h

4.33±0.05d

5.11±0.06ab

3.33±0.04ef

4.32±0.02d

4.78±0.04b

5.45±0.05a

4.55±0.59c

4.94±0.34b

4.40±0.01cd

4.71±0.03b

5.75±0.11ab

3.22±0.14e

3.94±0.10cde

3.46±0.16de

3.96±0.02cde

3.34±0.04e

6.15±0.23a

0.28±0.01h

0.26±0.03i

0.31±0.02f

0.34±0.01d

0.34±0.01d

0.36±0.10b

0.25±0.05j

0.35±0.01c

0.32±0.10e

0.34±0.10d

0.45±0.01a

0.28±0.04a

0.26±0.10b

0.23±0.01ef

0.25±0.04bc

0.25±0.00bcd

0.22±0.003f

0.24±0.003cde

0.23±0.00ef

0.24±0.00d

0.20±0.00g

0.16±0.10h

0.35±0.06a

0.34±0.08a

0.34±0.08a

0.33±00ab

0.34±0,.08a

0.29±0.00d

0.30±0.06cd

0.31±0.00bc

0.30±0.06cd

0.25±0.04e

0.15±0.15f

Mean that do not share letters vertically are significantly different. Values are mean of three independent determinations



Table3. 3 Result showing individual catechin compounds obtained by high pressure liquid chromatography (HPLC) analysis

Wall material

MD:GA:CTS(%)

C EC EGC EGCG GCG ECG TC (mg/100g)

100:00:0 73.78C 478.91

abc 2330.33

d 3963.67

d 380.06

bc 803.56

abc 8042.90

bcd

00:100:0 77.72C 502.57

abc 2449.99

c 4468.89

b 350.02

cd 844.55

abc 8687.90

ab

75:25:0 72.38C 545.87

ab 2681.22

a 4558.06

ab 437.34

ab 924.49

a 8019.09

bcd

50:50:0 73.78C 528.23

ab 2455.01

c 4173.52

c 338.62

cde 680.86

bc 8232..20

bcd

25:75:0 69.90bc

578.99a 2540.29

bc 4371.71

b 308.72

def 532.48

abc 8404.88

bcd

99:00:1 81.48c 318.99

de 2138.29

e 3746.08

e 281.21

efg 131.34

c 7313.57

bcd

00:99:1 130.33c 90.72d

e 1968.36

f 3480.93

f 286.64

efg 767.14

abc 7217.85

cd

75:24:1 132.33a 431.77

bcd 2125.98

e 3669.09

e 275.51

fg 835.00

ab 7722..10

cd

50:49:1 98.62ab

358.35de

1968.95f 3405.78

f 235.06

g 706.34

abc 7114.25

d

25:74:1 86.95bc

296.19e 1938.78

f 3336.93

f 363.28

cd 745.78

abc 7046.70

d

GTE 90.03bc

574.78a 2582.99

ab 4704.55

a 423.22

a 651.91

bc 9867.20

a

Results are mean ± SD of three determinations of catechin microparticles based on 5% carrier materials used. Means values in columns carrying the

Same superscript letters are not significantly (p ≤ 0.05) different.



Fig. 3.1. Encapsulation efficiency of total catechin entrapped. Values are means of three independent determination ± SD. Means carrying different letters are

significantly (p ≤ 0.05) different (Turkey’s multiple- range test

Fig. 3.2. total polyphenolic content green tea catechin microparticles entrapped using different wall material. Values are means of three independent determination

±SD.Values carrying different letters are significantly different (p ≤ 0.05) different.

Fig. 3.3. Antioxidant activity of green tea microparticles as determined by DPPH assay. Values are means of three independent determinations ± SD. Values

carrying different letters are significantly (p ≤ 0.5) different (Turkey’s multiples –range test).



Fig. 3.4. (a) Effects of incubation on simulated gastrointestinal fluids (SGF pH 2.3) on the swelling behaviour of spray- dried microparticles. (MD- maltodextrin, GA – gum arabic, CTS –chitosan).

Fig. 3.4(b). Degree of swelling of catechin microparticles in (SGF) Values are presented as means± SD. Values that carry different letters are significantly (p ≤

0.05) different (Turkey’s multiple –range test).

Fig. 3.5 (a). Effects of incubation on simulated intestinal fluids (SIF pH 7.4) on the swelling behaviour of spray- dried microparticles: (MD- maltodextrin, GA –

gum arabic, CTS –chitosan).



Fig. 3.5 (b). Degree of swelling of catechin microparticles in SIF condition; values are presented as means ±SD. Values that carry different letters are

significantly (p ≤ 0.05) different (Turkey’s multiple –range test).

Fig. 3.6a. Change in pH of supplemented mango drink during stored at 4oC for 4 weeks

Fig. 3.6b.Change in total solid (oBrix) of supplemented mango drink during 4oC for 4 weeks



Fig. 3.6c. Changes in viscosity of supplemented mango drink at during storage

Fig.7a. HPLC chromatogram of catechin standards

Fig. 6b Fig.7b.Representative HPLC chromatograms from Supplemented mango drink (week 0)

Fig. 3.7c. Representative HPLC chromatograms from Supplemented mango drink (wee 4)

a



b

c

Fig. 3.8. Stability of catechin microparticles on catechin –supplemented mango drinks at (a) 0.5%, (b) 1.0 (c) 2.0% concentrations. Values are presented as the

means of three replicate determination ± SD.

Fig. 3.9. Percentage degradation of green catechin in Mango drink during 4 weeks storage at 4oc. Values carrying different letters are significantly ( p ≥ 0.05)

different. Values are presented as means ± SD.

a



b

Fig. 3.10. (a) Changes in total phenolic content of catechin microparticles released in catechin-mango drink stored at 4oc for 4weeks, (b) changes in antioxidant

activity of catechin- mango drink supplements at 4oC for 4 weeks. Values are presented as the means of three replicate determination ± SD.

microencapsulation of green tea extracts and its effects...

Documents