TATUM SNYDER AND AJILA CHANDRAN MATHEYAMBATH
Abstract
Polyphenols are plant-derived bioactive compounds characterized by the presence of one or more phenolic rings and play a vital role in defining the sensory and physico-chemical properties of beer, including flavor, mouthfeel, haze formation, and antioxidant activity. In brewing, malt and hops are the primary sources of polyphenolic compounds. Understanding the biotransformation of malt-derived polyphenols during fermentation is key to optimizing beer quality. This study investigates the effects of Ale yeast fermentation on the polyphenolic composition of barley malt. Yeast fermentation was performed for five days in a growth medium supplemented with wort derived from Great Western 2-Row Pale Malt at concentrations of 0%, 0.5%, 1%, 5%, and 10%. Polyphenols were extracted from fermentation samples, quantified, and further characterized using liquid chromatography-mass spectrometry. The results demonstrate that ale yeast fermentation induces significant changes in the polyphenolic profile of the malt, indicating active biotransformation. These findings provide insights into yeast-mediated modifications of polyphenolic compounds during fermentation and offer potential strategies for enhancing beer quality through controlled biotransformation.