Effect of different microencapsulating materials and relative humidities on storage stability of microencapsulated grape pomace extract

摘要

This work aims to prolong the storage stability of polyphenols, obtained from grape pomace, using a spray drying-based microencapsulation technique. The microcapsules obtained under optimal conditions were stored at two different relative humidifies (33% and 52%) during 75 days. The analyses of total phenolic content, antioxidant activity, and individual phenolic compounds were carried out every 15 days, and the most stable microcapsules were achieved with maltodextrin DE4-7 prepared by adding gum Arabic to the wall material at a ratio of 8:2. The phenolic content loss rate was found to be in a range of 0.93-5.42 % depending on phenolic compound. The decrease in the content of rutin, chlorogenic acid, epicatechin, caffeic acid, gallic acid, caftaric acid and catechin was only 0.93, 2.09, 2.13, 2.27, 2.41, 3.40 and 5.42%, respectively. These results indicate more efficient storage conditions than those of previously reported studies.