Impregnation of açaí residue extracts in silica-aerogel

Abstract

Açaí (Euterpe Oleracea mart.) is a berry found in Amazon Rainforest, with a high content of polyphenols and flavonoids. This work studied the formulation of bioactive compounds extracted from E. Oleracea fruit, by impregnation in silica-aerogel. Three fruit fractions were studied: pulp, seeds and slurry, and two extracts were obtained from each fraction: an oil fraction obtained by Soxhlet extraction, and a polyphenolic-rich extract obtained by Pressurized Microwave Assisted Extraction. With pulp oil, impregnation yields of 58.6% were obtained by air drying, with surface area of 0.7687 m²/g, while with supercritical drying method, the impregnation yield decreased to 15.3%, with surface area of 823.4 m²/g. This indicates a loss of oil by extraction during drying. With pulp extract, the best result was obtained using indirect wet impregnation and supercritical drying, with 16.4% of impregnation. By release assay, contents of 2.276 mg/g(aerogel) of polyphenols and 0.197 mg/g(aerogel) of anthocyanins were identified.