Microencapsulation of flaxseed oil by soya proteins–gum arabic complex coacervation

Abstract

Summary Application of soya proteins (SP) in flaxseed oil microencapsulation based on complex coacervation was investigated. The effects of SP /gum arabic ( GA ) mixing ratio (1:2, 1:1 and 2:1) and pH (2.80, 3.15 and 3.75) on coacervate preparation were studied firstly. The highest coacervate yields ( CY ) were achieved at SP / GA = 1:1, pH 3.15, and SP / GA = 2:1, pH 3.75, which were 81.2 ± 2.0%, 88.1 ± 0.6%, respectively. Thereafter, the microencapsulation of flaxseed oil was detected in accordance with the results of the coacervation of SP / GA , that is the optimal condition for microencapsulation was corresponded to the condition where CY was the highest. Under the conditions of SP / GA = 1:1, pH 3.15, and SP / GA = 2:1, p H 3.75, the microencapsulation efficiency and total yield reached 81.5 ± 0.1% and 81.7 ± 0.4%, and 77.4 ± 3.7% and 86.7 ± 2.4%, respectively. Microscopic morphology revealed that the formation of a biopolymer shell around the oil droplets was achieved at specific conditions.