Abstract

The use of brewing adjuncts can improve the color, aroma, and flavor of beer. Sweet potatoes (Ipomea batatas) are rich in bioactive compounds, such as phenolic compounds with antioxidant activity. Thus, this study aimed to develop and characterize physicochemical and sensorial aspects of craft beers brewed with sweet potatoes with purple and yellow flesh. Three beer formulations were prepared: 50% purple-fleshed sweet potato and 50% barley malt, 50% purple plus yellow-fleshed sweet potato and 50% barley malt, and also 50% yellow-fleshed sweet potato and 50% barley malt. The alcohol content of sweet potato beers ranged from 4.5 to 6.0% (v/v). The total phenolic compounds content of sweet potato beers ranged from 110.44 to 160.86 mg/100 mL and the antioxidant activity values of sweet potato beers ranged from 2.38 to 3.22 mM TE/mL by ABTS and 1.17 to 2.56 mM TE/mL by 2,2-diphenyl-1-picrylhydrazyl (DPPH). The sweet potato beers had good sensory acceptance, obtaining scores of 7.0 to 8.2 for the overall impression, with the purple and yellow-fleshed sweet potato beer being preferred by the evaluators. The beers showed high antioxidant activity and concentration of phenolic compounds, showing that sweet potatoes are a promising brewing adjunct to produce craft beers.

Key words: Craft beer, sweet potato, Ipomea batatas, antioxidant activity, phenolic compounds, sensory characteristics.