Spectroscopic Determination of Glycerol, Polyphenols, and Nitrogenous Compounds in Beer and Wine

Gorinstein, S., Kitov, S., and Deutsch, J.

Abstract
The Infrared and Ultraviolet systems were used for the determination of glycerols and polyphenols in beer and wine. Comparison is made with the standard methods (Soxhlet, acetone weight extractable, and carboxymethylcellulose), and results for all methods are presented. Results from the Infrared and Ultraviolet methods are lower due to the presence of only glycerols or phenols. Quantitative differences in these components that are dependent on the amounts of raw materials and enzymes in beer have been found. Glycerol, polyphenols, and low molecular weight nitrogen compounds were reported in relation to the physical, chemical, and organoleptic properties, and with respect to the foam stability, viscosity, and chillproofness of the final product.