Profiling of carbohydrates in commercial beers and their influence on beer quality.

Abstract

The carbohydrates in beer play an important role as they are essential for fermentation. Any change in their composition may influence the sensory characteristics of the beer and so their determination is of great interest. This study compares the carbohydrates in three types of commercial beer - barley malt beer, wheat beer, and barley malt beer with adjuncts - and examines their influence on beer quality, which is important for selecting raw ingredients and production conditions, and for quality control. Among the oligosaccharides in three types of beer, raffinose was the most, followed by maltotetraose, maltotriose and maltose. Monosaccharides were only present in small amounts. Dextrin, oligosaccharides with 2-6 polymerization degree and non-starch polysaccharides (NSP) make up 15.90-34.83%, 17.59-38.63%, and 2.33-7.47% of the total carbohydrates in beer, respectively. The dextrin content and NSP content were significantly (P < 0.05) different in wheat beer and barley malt beer, and their content was significantly (P < 0.01) correlated with the content of extracts in beer. Non-starch polysaccharide, dextrin, trisaccharide, and tetrasaccharide content significantly (P < 0.05) correlated with beer viscosity. These beer samples could be categorized clearly into three groups by principal component analysis. The oligosaccharides in beer reflect yeast utilization, depending on the type of beer. Dextrin, oligosaccharides with 2-4 polymerization, and NSP, were major carbohydrates in beer. Their composition and concentration influenced its characteristics and quality, and played an important role in the discrimination of different beer types. © 2020 Society of Chemical Industry.