Physicochemical and dynamic sensory characterization of a Yerba mate/Blackcurrant instant beverage powder rich in natural antioxidants

Abstract

BACKGROUND: Yerba-mate (YM) and blackcurrant (BC) are rich in polyphenols and anthocyanins with proven health benefits therefore they could be used in functional beverage preparation.OBJECTIVE: To (a) develop a palatable powdered beverage with high physicochemical and nutritional quality using YM/BC, (b) determine the effect of in-vitro gastrointestinal digestion on antioxidant content and activity and (c) evaluate beverage?s acceptance temporal changes and dynamic profile during multiple intakes.METHODS: We determined powder?s water-activity (aw), moisture content, flowability, micro-morphology, color, cold water solubility, glass-transition temperature (Tg), total polyphenols (TP)/anthocyanins (MAC) and ascorbic-acid contents, antiradical activity (DPPH).RESULTS: Powder?s aw (0.089) ensured biochemical/microbiological stability. Tg(55.64◦C) indicated that YM/BC?s vacuum- storage at 20?25◦C was possible without losing glassy state. Powder?s cold water?s solubility was 90%. 1 L (60 g/L)provided 556.8mg TP/198.11mg monomeric-anthocyanins. Ascorbic- acid dose was half the recommended daily intake. In-vitro gastrointestinal digestion reduced total polyphenols/monomeric-anthocyanins 59?70%, but antiradical activity losseswere 9%. Overall-acceptance and Time-Intensity curves results were in the Hedonic scale?s ?Like moderately to like very much? zone. Berries/Sweet were the only dominant attributes Astringency accumulative effects not detected.CONCLUSIONS: The YM/BC powder had good physical/biochemical/microbiological stability under industrial storage conditions and high antiradical activity after simulated gastrointestinal digestion. Sensory scores suggested that consumer?s acceptance could be high.