Formação e aplicação de coacervados complexos heteroproteicos de óleo de chia (Salvia hispanica L.) para iogurte adicionado de ácidos graxos poliinsaturados

Abstract

Heteroproteic systems can be used to encapsulate vegetable oils rich in polyunsaturated fatty acids, enabling their use as an ingredient with potential functional benefits in foods, in addition to increasing the protein content of the foods in which they are incorporated. The present study aimed to use type-A gelatin (GA) and chia protein concentrate (CPC) to encapsulate chia oil (OC) via complex coacervation and apply it to yogurts to add polyunsaturated fatty acids. The CPC and GA complex coacervates were formed in a 1:1 (w/w) ratio at pH 5.0 and a biopolymer concentration of 0.5 % (w/v), with a yield of 93.2 % and an encapsulation efficiency of 90.4 %. The microcapsules were incorporated into the yogurt at concentrations of 2 % and 4 %, and the enriched yogurts were evaluated during 28 days of storage. During this period, the addition of microcapsules to the yogurt did not alter the pH or acidity, resulted in a darker color as observed by colorimetry, reduced the syneresis effect, and increased the product’s firmness. The sensory evaluation of yogurts with and without microcapsules, analyzed using an acceptance test, indicated that the sample without added microcapsules showed higher overall acceptance (7.9) and purchase intention (4.4±0.83), followed by the samples incorporating 2 % and 4 % microcapsules. The intensity perception analysis indicated that the samples incorporating microcapsules did not show a significant difference compared to the sample without addition in the attributes “presence of particles,” “sour taste,” and “homogeneous appearance,” exhibiting a strong homogeneous appearance and weak perception of particles and sour taste. It is concluded that it was possible to encapsulate chia oil through complex coacervation in a heteroprotein system, and the microcapsules showed potential for application in yogurts fortified with polyunsaturated fatty acids.