Kvasny Prum. 1972; 18(5): 101-103 | DOI: 10.18832/kp1972007

Methods used in brewing industry for the determination of free amino acids and amino nitrogen.Peer-reviewed article

G. BASAŘOVÁ, I. ČERNÁ

The article deals with several methods which are at present applied in the laboratories of brewing industry for determining free amino acids and amino nitrogen. Preparing samples for an automatic analyzer of amino acids the authoresses ascertained losses in the samples of sweet wort, wort and beer caused by preparatory operations, viz. by lyophilization, separation of amino acids on the DOVEW 50-X4 column and separation of macromolecular nitrogenous compounds through precipitation by trichloracetic acid. It has been established that losses of amino acids can be reduced to minimum by sample lyophylization . If samples with high percentage of macromolecular substances, as e.g. samples of sweet wort or wort, are to be analyzed in an automatic analyzer, amino acids should be separated on the DOVEW 50-X4 column to prevent losses of basic amino acide. Methods used in laboratory for determining conveniently amino nitrogen are also dealt with. The TNBS method gives comparatively very accurate results differing only slightly from results calculated from aminograms obtained by analyses in automatic analyzer. The amount of amino nitrogen is always related to the attenuation degree. If samples of various compositions and origins are to be compared, it is necessary to use the same analytic method.
(In Czech, English summary only)

Keywords: brewing industry, amino acids, amino nitrogen, determination

Published: May 1, 1972