Phytochemical Composition and Pigment Stability of Açai (<i>Euterpe oleracea </i>Mart.)

TLDR

Açai is valued for its functional properties in food and nutraceutical products. The study quantified anthocyanins and polyphenolics in açai, measured their antioxidant capacity, and evaluated anthocyanin color stability against hydrogen peroxide (0–30 mmol L⁻¹) across 10–30 °C, including comparisons to other sources and tests in a beverage model with ascorbic acid and polyphenolic cofactors. Cyanidin‑3‑glucoside dominated açai anthocyanins and correlated with antioxidant activity, while 16 other polyphenolics were present; compared to red grape, açai anthocyanins were less stable to hydrogen peroxide and temperature, but acylated anthocyanins showed improved stability when combined with ascorbic acid.

Abstract

Anthocyanin and polyphenolic compounds present in açai (Euterpe oleracea Mart.) were determined and their respective contribution to the overall antioxidant capacity established. Color stability of açai anthocyanins against hydrogen peroxide (0 and 30 mmol/L) over a range of temperatures (10-30 degrees C) was also determined and compared to common anthocyanin sources. Additionally, stability in a model beverage system was evaluated in the presence of ascorbic acid and naturally occurring polyphenolic cofactors. Cyanidin 3-glucoside (1040 mg/L) was the predominant anthocyanin in açai and correlated to antioxidant content, while 16 other polyphenolics were detected from 4 to 212 mg/L. Red grape anthocyanins were most stable in the presence of hydrogen peroxide, while açai and pigments rich in acylated anthocyanins displayed lower color stability in a temperature-dependent manner. In the presence of ascorbic acid, acylated anthocyanin sources generally had increased color stability. Açai was recognized for its functional properties for use in food and nutraceutical products.