| CLN is similar as CLA,with the function of anti-cancer,anti-tumour, decreasing the sugar content in blood,adjusting the immunity,and the activity of CLN is more excellent than CLA.CLN partly exists in plants with the formation of glyceride in nature,α-eleostearic acid is a kind of CLN. It is known that bitter gourd seeds oil contains plenty ofα-eleostearic acid,which almost exists in inedible source,meanwhile,the value of bitter gourd seeds oil has been gotten more and more attention.Owing to its odor and bad-tasting,combining with its feature of easily oxidation and being isomerization by light and tracemetal,bitter gourd seeds oil is restricted applying in foods and health products.In this study,the technique of complex coacervation method is used to solve the problem which is mentioned above.The condition of preparing the microcapsule and the method of mensurating was investigated. The extracting solvent of total oil quantity was a blend of ethanol, aether and petroleum ether,with the ratio of 3:2:1 and the extracting time of 3h;the extracting solvent of surface oil quantity was aether,with the extracting time of 3min. The final optimized parameters were:pH 3.9,ratio of core/wall 1:2,wall-material concentration 1%,span80 with the concentration of 0.1%(m/m) emulsification system as emulsifier,the temperature of coacervaion 45℃, stirring speed 370rpm～400rpm,the ratio of TG to gelatin 0.25g·g-1gelatin,crossing-linking time 4h.Using the above-mentioned conditions,satisfying morphology appeared,with the yield of 87.7% and the efficiency of 90.9%,meanwhile,the average size of microcapsules was 52.376μm.The feature of the microcapsule was investigated,including the moisture content after spray-drying of 2.25%,the superstructure of microcapsule,the glass transition temperature of 45℃by DSC.The result of thermogravimetric analysis showed that the core material was well protected by wall materials.AMP-derivatization was used to analyse the composition of bitter gourd seeds oil,showing that the oil contains 30%α-eleostearic acid.The problem of oxidation during the course of preparing and storing was also investigated.Adding antioxidant,double encapsulation and protecting by N2 were used to solve the problem above.POV value was utilized to evaluate the effect of anti-oxidation.The mixture of TBHQ and LTP was used as the complex-antioxidant,with the ratio of 2:5 and the amount of 2100 meq·kg-1.By comparing different kinds of wall materials used in double-encapsulation with the temperature of 25℃and 45℃,it was found that satisfying anti-oxidation effect would be gotten,with the wall material of casein and reducing sugar.So shelf life of the product was extended.Finally the volatile composition of bitter gourd seeds oil,moist microcapsule,microcapsule dried by spray-drying,microcapsule by freeze drying was analysed.The results showed that the odor of bitter gourd seeds oil was successfully masked by the method of complex coacervation combining with double encapsulation.The point mentioned above was demonstrated again by the sensory evaluation of adding spray-drying microcapsule into pure milk.
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