beverages Review Beer Polyphenols—Bitterness, Astringency, and Off-Flavors Kristina Habschied 1,* , Iztok Jože Košir 2 , Vinko Krstanovi´c 1 , Goran Kumri´c 3 and Krešimir Mastanjevi´c 1 1 Faculty of Food Technology, Josip Juraj Strossmayer University of Osijek, F. Kuhaˇca20, 31000 Osijek, Croatia;
[email protected] (V.K.);
[email protected] (K.M.) 2 Slovenian Institute of Hop Research and Brewing, Cesta Žalskega Tabora 2, 3310 Žalec, Slovenia;
[email protected] 3 European Food Safety Authority, Via Carlo Magno 1a, 43126 Parma, Italy;
[email protected] * Correspondence:
[email protected]; Tel.: +385-31-224-300 Abstract: The acceptance of beer among consumers is most influenced by the taste and aroma. Polyphenols are widely responsible for both. Whereas polyphenols do not always result in a positive flavor and taste, they can surely impart certain off-flavors, which will be mentioned in this paper. However, the aftertaste is an important component of the beer-tasting experience and acceptance. The aftertaste, including astringency, may largely influence consumers’ consumption preference and behavior. Bitterness is one of the main, desirable characteristics of beer, but to an untrained consumer, it can often be mistaken with astringency. This review aims to describe the differences between these two properties. Both attributes derive from the same beer components, polyphenols from barley and hop, but there is a distinctive difference between them. To understand the complexity of bitterness and astringency, polyphenols behavior, characteristics, and stability during the brewing process are also described in this review. Citation: Habschied, K.; Košir, I.J.; Keywords: bitterness; beer; aftertaste; off-flavor Krstanovi´c,V.; Kumri´c,G.; Mastanjevi´c,K.