Tgp chi khoa hgc - Cong nghe Thuy Sdn
EFFECT OF CARRAGEENAN ADDITION IN ENCAPSULATION OF GAC OIL USING GELATIN GELATION METHOD
ANHHlf&NGCUA VIEC BO SUNG CARRAGEENAN TOI KHA NANG VINANGHO.i DAU GAC THEO PHl/ONG PHAP TAO GEL MREN .\EN CHAT BAO GELATIN
Tran Hai Dang', Le Thi Ha-, 4n Thi Tuoi', Ta Thi Minh Ngec^
Gac oil contents a precious sources of carotenoids which ai c benefit lo health but sensitive to oxidation Encapsulation is an efficient technology that help to trap-md protect fragile mulerial in a polymer shell in micro-size. In this study, encapsulation of gac oil using gelation method based on gelatin systm was investigated wilh or without addition of a well-known .marine polymer - carrageenan. Several points were studied: viscosity of polymer system, life time of emulsion, distribution of emulsion droplets' m, encapsulation efficacy ... The results showed that addition of carrageenan increased clearly viscosityaf polymer emulsion. This addition also enhanced the encapsulation efficacy hul not in all the cases Formatim of microcapsule was obtained with emulsion which had a viscosity higher Ihan about 30 cP and il is as easier as viscosity increased Otherwise, gelatin seemed lo express a more ptistlive effect in encapsulation efficaa Ihan carrageenan
Keywords: Gac oil. encapsulation, carrageenan, gelatin, gelalioii
Carotenoids Id ngudn chdt chdng oxy hoa tdt cho stic khde vd cd nhiiu Irong ddu Gdc Tuy nhien.
carotenoids rdt nhgy cdm vdi dieu hen mdi trudng. Tgo vi nang Id mot cdng nghe huu hieu nhdm bdo ve cac hoat chdt khoi tdc dpng mdi trudng bdng cdch bao goi chung vao trong mdt Idp vo polymer & tdch ihm micro. Trong nghien ciru nay, ddu gdc duac bao vi nang bdng phuang phdp tao gel vdi gelatin. Viec bSsung carrageenan vdo hf polymer ldm Idng ro ret do nhdi cua nhu Hrang ddu/ nude Nhin chung, viec bd sung carrageenan ldm tang hieu qud bao gdi. Viec Igo vi nang cd the thuc hien duac vdi he nhti luang co do nhin tif 30 cP trd len. Tuy nhien. hieu qud bao goi it bi dnh hudng bai carrageenan
Tir khoa: Ddu gdc, vi nang, carrageenan, gelatin, gel hda
I. INTRODUCTION
Gac oil is a Vietnamese traditional product which contents a high concentration of interesting carotenoids like p-carotene and lycopene which are very useful in cancer treatment and anti-aget) protection due to their strong antioxidant activity {Aoki et al 2002) However, its hydrophobicily
Institute of Biotechnology and Environment, Nha Trang University
^Faculty of Food technology. Nha Trang University
* ta tm [email protected]
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So Ddc biet - 2013
jstrains its uses in food applications which are normally aqueous systems. Encapsulation could help ) transform liquid oil into fluid powder and protect the core material in a micro-sized shell (Gonnet t al. 2010). Beta-caroten synthetised by the mold Blakeslea trispora was succesfully encapsulate I gelatin as carrier matrix, based on phase separation principle (Vuong et al. 2005). The continous hase of double emulsion was paraffin which required a wash step by solvent after encapsulation.
his is an inconvenient point for food purposes.
In this study, we have investigated a new simple processe which was always based on gelation haracteristic of gelafin but only on step of emulsification. Carrageenan was added in order to nhance the gelation and to reduce percent of wall material.
. MATERIALS AND METHODS . Materials
Gac oil was purchased from Vnpofood which contents 150 mg% of beta-carotene. Carrageenan /as food grade carrageenan imported from Phillipine. Other chemicals of reagent grade were nported from China or India.
:. Preparation of Gac oil emulsion
Gac oil emulsion was prepared in polymer's solutions with ratio of 4ml Gac oil for 100ml solution if mixture of gelatin (5 - 20%) and carrageenan (0.1 - 0.5%). The mixture was homogenized at 4 larsfor 10 minutes using the h o m o g e n i z e r l K A T I 8 Basic, ULTRA_TURRAX (Tran e t a l . 2012).
i. Determination of emulsion stability
Emulsion life time. The emulsion prepared was filled in Nessler tube and left at room temperature D observe phase separation through appearance of phase's visible boundary (Weiss 2000).
Emulsion droplets size. The emulsion droplet size was determined under microscope, using the oftware Motic Image 2.0.
•. Viscosity measurement
Viscosity of biopolymer solution at different concentrations was measured using the viscometer ) V - I Prime Brookfield.
'•. Preparation of microcapsules
Microcapsules were formed by drop the emulsion into aquatic solution with stirring at low smperature (2 - 14°C). Microcapsules were then harvested and analyzed for encapsulation efficacy.
Gac Oil I >| Gelatin solution | < — | Carrageenan |
I Homogenification |
Figure I . D i a g r a m o f capsule p r e p a r a t i o n
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Tap chi khoa hoc - Cong nghe Thuy Sdn
- ^
III. RESULTS AND DISCUSSION
1 Effect of carrageenan addition on stability of gac oil - gelatin emulsion
Effect of carrageenan addition on stability of gac oil - gelatin emulsion was investigated througli system viscosity and evolution of emulsion volume fraction. In theory, emulsion stability has a relation with its viscosity or concentration of polymers. Results showed that emulsion viscosity increased with concentration of gelatin (Fig. 2). Viscosity of continuous phase could decrease the Brown's movement of dispersion droplets and than slow down phase separation. In fact, emulsion was more stable with higher concentration of gelatin and in presence of carrageenan (Fig. 3A, 3B).
In the range of studied concentrations, addition of carrageenan at concentration of 0.1% was not significantly change the viscosity of the system. Otherwise, addition of 0.5% carrageenan increased considerably this viscosity. ^ ^ ^ ^ ^ ^ _ ^
Cerrageenan 0.1 % -*-Gelatln + Carrageenan 0.5%
ConcMitrabon o( galilki (%)
Figure 2. Effect of carrageenan on viscosity of polymer phase
Volume fraction is an index that reflects relation between density of emulsion, density of continual!
phase and density of dispersion phase. As the two last one do not change during processing, evolution^
volume fraction in time corresponds to stability of emulsion. The more this index is constant, the mora emulsion is stable. At the same concentration of gelatin (20%), addition of carrageenan increased dramatically the stability of emulsion (Fig. 3A). Previous study (Tran et al., 2012) has showed thai viscosity of gelatin solution was in square relation with its concentration. Fig. 2B showed an only slightly difference of volume fraction's evolution between solution of 10%, 15% and 20% in presence of carrageenan 0.5%. This result showed that addition of carrageenan ameliorate strongly the stability of emulsion. This effect is not only due on augmentation of viscosity (Fig. 2).
OflB
Changa In voluma fraction
i i f 1 1 1 1 1
f
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f ™ : l i
1 ™ ^ = ^
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Tana (min)
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500 IDOO ISW T i m e ( m i l )
(A) gelatin 20%
0.5%. (C) gelatine
Twnmjtnm) | Tnia(min) | r»na(i Figure 3. Effect of carrageenan on emulsion stability
)% with carrageenan 0% (*), 0 1% (a). 0 5% (A), (B) gelatin 10% (A). 15% fl), 20% (*) e 20% (*). gelatin 15% with can-ageenan 0 5% )||)
witti carrageea
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:. Effect of carrageenan addition on gac oil encapsulation
We have investigated the encapsulation efficacy of different polymers systems mixed between lelatin and carrageenan.
Fig. 4 presents the encapsulation efficacy in relation with polymer viscosity and polymer ancentration. Results were distingued in three groups depending on the polymer viscosity. The ligest viscous system (80.5 cP) also the most stable emulsion (gelatin 20% + carrageenan 0.5%)
!xpressed a higest encapsulation efficacy.
Three systems including gelatin 20%, gelatin 20% + carrageenan 0.1 %, gelatin 15% + carrageenan ).5% which had moyen viscosity (around 60 cP) expressed similar encapsulation efficacy (Fig. 4, jroup B). This group showed no effect of polymer origin in encapsulation efficacy even their emulsion itability was quite different (Fig. 3A, 3C). This may be explained by short during ofthe encapsulation )rocess which was complet before phase separation o f t h e emulsion.
Two systems of polymer which had a low viscosity (around 30 cP) but expressed different jfficacy in encapsulation were gelatin 10% + carrageenan 0.5% and gelatin 15% + carrageenan 3.1%. In this case, origin of polymer seemed to play a more important role in encapsulation than ts viscosity (Fig. 4, group A). A less viscous system showed unablity in encapsulation (results lot showed).
In all case (group A and B), at similar viscosity, system which had higer concentration in gelatin showed more efficient encapsulation. For example, system of gelatin 20% without carrageenan
;57.7 c P ) h a d t h e s a m e e n c a p s u l a t i o n e f f i c a c y ( 0 . 0 5 1 | j g / g) w i t h s y s t e m of g e l a t i n 15% + carrageenan 0.5% (64.0 cP).
In order to estimate the influence of encapsulation process on Gac oil quality, Gac oil encapsulated was extract with n- hexan for UV - VIS analysis. Results showed the same apparence of spectre aetween encapsulated and origin Gac oil which means that encapsualtion processus did not affect [he quality of Gac oil (Fig. 5).
0 3 - o» - 0,7 Ofi- 0 ^ - 0,4 0,3 - OA 0 4
31
/ / A
C'^lC^/ A
» 350 flOO 450 500 550
Figure 4. Encapsulation efficacy (open symbol) in relation with polymer concentration (close symbol) and viscosity
(gelatin - triangle; carrageenan O.iyo - circle; carrageenan 0,5% - square)
Figure 5, Spectre of carotenoids extract from Gac oil (continous line) and from
Gac oil capsule wilh gelatin 10% -<- carrageenan 0.5% (dashed line)
V. CONCLUSION
Gac oil was encapsulation using gelation method based on gelatin - carragenenan system.
Addition of carrageenan showed an improvement in emulsion stability and encapsulation efficacy.
TRU3NG D A l HOC NHA TRANG • 6 1
Tgp chi khoa hgc - Cong nghe Thuy Sdn
Despite the role of carrageenan in improvement of viscosity which influenced emulsion stabilisatiofi, gelatin seemed to play a more important role in efficacy of encapsulation process.
REFERENCES
1. Aoki, H. et al., 2002. Carotenoid pigments in GAC fruit (Momordica cochinchinensis SPRENGi Bioscience, biotechnology, and biochemistry, 66(11), pp.2479-82.
2. Gonnet, M., Lethuaut, L. & Bouiy, F., 2010. New trends m encapsulation of liposoluble vitamins. Jounal of controlled release : officialjoumal ofthe Controlled Release Society, 146(3), pp.276-90.
3 Tran, H.D., Le, A.N. & Ta, T.M.N., 2012. Dispersion of gac's oil in aqueous phase: effect of polymer and homogenous conditions. Joumal of Science and Technology.
4 Vuong, N.M. et al., 2005. Microencapsulaion of beta-carotene synthesized from Blakeslea trispora, ti Regional Symposium on chemical engineering. HaNpi, VietNam, pp. 3 1 0 - 3 1 5 .
5. Weiss, J., 2000. Emulsion stability detemiination. In R. E Wrolstad et al., eds. Handbook of food anaiytial chemistry handbook of food analytical chemistry. John Wiley & Sons, Inc., pp. 591 - 608.
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