Enzymatic Modification of Polyvinylpolypyrrolidone (PVPP) for Improved Adsorption of Proteins and Polyphenols Causing Haze in Beer

Abstract

Nonbiological turbidity is an issue that affects the quality and consumer perception of various types of beer. This characteristic arises from the interaction between polyphenols and proline-rich proteins. To tackle this problem, many breweries utilize adjuncts like PVPP (polyvinylpolypyrrolidone) to eliminate polyphenols, while silica gel removes the proteins responsible for turbidity. Our research investigated the enzymatic modification of PVPP to enhance protein adsorption. The modified PVPP demonstrated a protein removal capacity 4.66 times greater than its unmodified counterpart and significantly decreased polyphenol concentration (198.00 mg/g) compared to unmodified PVPP (143.50 mg/g). Additionally, the modified PVPP was more effective at lowering beer turbidity (13.20%) than unmodified PVPP (4.99%) and silica gel (3.06%). These findings indicate that the modification of PVPP, using a mild methodology, produced a material with high efficiency in reducing beer turbidity, capable of improving beer stability and increasing consumer acceptance.