A New Synthetic Mehtod Of Functional Food Additive－Soybean Oleic Acid Sucrose Polyesters

In this paper, soybean oleic acid sucrose polyester was synthesized through two-step way. Here, soybean oleic acid potassium soap was employed as emulsifier, anhydrous potassium carbonate was used as catalyst, and cetyltri methylammonium bromide was used as phase-transfer catalyst.Firstly, soybean oleic acid ethyl ester was synthesized by soybean oil and and ethanol. Factors such as the amount of ethanol, the amount of catalyst-KOH, reaction time, and reaction temperature, etc were studied for the optimal synthesis conditions. The result shows that the amount of ethanol was exceeding two times of the theoretical amount, the amount of catalyst KOH was 1.2%, the reaction time was about 7h, and the reaction temperature was about 78℃, the yield of the soybean oleic acid ethyl ester reached the highest, and the quality was the best at the same time.Seconly, the soybean oleic acid sucrose polyester was synthetized by the as-sythesized soybean oleic acid ethyl ester and sugar. The optimal condition was determined by the amount of potassium carbonate, the amount of soybean oleic acid potassium soap, reaction temperature, reaction time, and soybean oleic acid ethyl ester, etc. The result shows that the amount of catalyst-K2CO3 was 2.5% of the weight of sugar, the amount of soybean oleic acid potassium was 5% of the weight of sugar, the reaction temperature was about 130℃, the best ratio of ethyl ester to sugar was 12:1 during the 6 hours, the sugar conversion appraoches 100%, the soybean oleic acid sucrose polyesters yield reaches 88.3%.The structure of the product was preliminarily evaluated through IR spectrum, the measurement of the degree of esterification, the measurement of the acid value, the measurement of the iodine value and the relative density. The IR spectrum indicate that the soybean oleic acid has been added onto the bone of sugar, the the degree of esterification was 6.9, the acid value was 0.38, the iodine value was 134.2, and the relative density was 0.9346. All the above analyses suggested that the final product is definitely soybean oleic acid sucrose polyester, the degree of esterification of which is among the range of expect. The physicochemical properties of the product are close to those of the soybean oil, and the product is believed to be applied in the near future.