Microencapsulation of hibiscus bioactives and its application in yogurt

Abstract

The aim of this study was to evaluate the application of microparticles of anthocyanins from Hibiscus sabdariffa L. extract, obtained by ionic gelation, to commercial natural yogurt. Two ionic gelation techniques were used as follows: atomization (Spray Dryer B-290) and dripping (Encapsulator B-390). Microparticles produced were evaluated for size, morphology, color, and encapsulation efficiency (total phenolic compounds, anthocyanins, and antioxidant capacity). Hibiscus extract (1.5%–4.5%) and 20% of hibiscus microparticles, obtained by atomization or dripping, were applied to whole sweetened natural yogurt and fat-free natural yogurt. Samples were evaluated for sensory acceptance and color changes under refrigerated conditions after the application of different levels of hibiscus extract (1.5%–4.5%). The atomization technique generated smaller particles with a greater encapsulation efficiency of bioactive compounds. Application of free hibiscus extract (4.5%) and hibiscus microparticles (20%) in yogurt matrix proved to be technically feasible, providing color and functional appeal to the product, with good sensory preference. Novelty Impact Statement: The double emulsion followed by ionic gelation has allowed good retention of hibiscus anthocyanins. The atomization technique generated smaller particles with a greater encapsulation efficiency of bioactive compounds. Hibiscus extract combined with microencapsulated hibiscus promoted color and functional appeal to yogurt, with good sensory preference.