Oxidation of 6-O-arachidonoyl L-ascorbate microencapsulated with a polysaccharide by spray-drying

The oxidative stability at 37degreesC and 12% relative humidity of arachidonoyl moiety of 6-O-arachidonoyl (L)-ascorbate, which was synthesized through lipase-catalyzed condensation with L-ascorbic acid, was higher than that of unmodified arachidonic acid. Arachidonic acid and arachidonoyl ascorbate were microencapsulated with maltodextrin, gum arabic or a soluble soybean polysaccharide by spray-drying. The oxidation of arachidonic acid under the conditions was retarded by its microencapsulation with gum arabic or the soluble soybean polysaccharide. The oxidation of arachidonoyl moiety of the ascorbate encapsulated with gum arabic or the soluble soybean polysaccharide more slowly proceeded than unmodified or encapsulated arachidonic acid. The fractions of the unoxidized arachidonoyl moiety on day 29 were greater than 0.7. Thus, esterification of arachidonic acid with ascorbic acid and subsequent microencapsulation with gum arabic or the soluble soybean polysaccharide significantly improved its oxidative stability. (C) 2003 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.