Stability and bioaccessibility of anthocyanins from maqui (Aristotelia chilensis [Mol.] Stuntz) juice microparticles

The microencapsulation of maqui juice by spray-drying was studied as a strategy to protect anthocyanins in new value-added formulations. The objective of this research was to study the influence of each maqui-anthocyanin and encapsulating agent (inulin or sodium alginate) on the anthocyanin encapsulation efficiency, the stability during storage (160 days at 60 °C) and the bioaccessibility in in vitro digestion model. The highest encapsulation efficiency of anthocyanins (65.6-78.6%) was obtained with inulin. The chemical structure of anthocyanins also influenced the encapsulation efficiency; the highest was 78.6% for delphinidin-3-sambubioside-5-glucoside in maqui juice-inulin, and 51.2% for cyanidin-3-glucoside in maqui juice-alginate. For both maqui juice-inulin and maqui juice-alginate microparticles, the half-life values of delphinidin-3-sambubioside (198 days), delphinidin-3-glucoside (173-182 days) and cyanidin-3-glucoside (154-133 days) showed the lowest stability of 3-O-glycosylated anthocyanins. The bioaccessibility of anthocyanins of the maqui juice microparticles was 10% higher than maqui juice.