Antioxidant compounds from blackberry (Rubus fruticosus) pomace: Microencapsulation by spray-dryer and pH stability evaluation

This study aimed to extract antioxidant compounds from blackberry pomace using two solvents, microencapsulate them by spray dryer and evaluate their stability at different pHs. Two pure extracts (aqueous andhydroalcoholic) and two microencapsulated with maltodextrin were dried in spray dryer and analyzed for stability under different pHs with respect to color variation (ΔΕ), total phenolic compounds, anthocyanins,antioxidant activity, and kinetic degradation of anthocyanins in 7 days. Regarding the color, the microcapsules protected the samples. Microencapsulation with maltodextrin was efficient in reducing the degradation of anthocyanins against increased pH, greater stability of the encapsulated samples was observed in lower pHs, aswell as longer half-lives of anthocyanins, values from 2 to 7 times greater when compared to extracts. The use of water in the extraction proce’ss resulted in lower percentage loss in 7 days, which was advantageous in relationto other types of extractions using organic solvents.