Kvasny Prum. 1992; 38(11): 321-325 | DOI: 10.18832/kp1992029

Change of beer colour due to effect of nitrite.Peer-reviewed article

J. ŠAVEL, M. PROKOPOVÁ

Colour changes of 12% hopped wort and beer during the reaction with sodium nitrite in concentrations of 10 and 100 mg NO₂-.l^-1 at 10 and25 °C were determined. The final colour was given in the extinction values obtained at 430 and 450 nm and in the coordinates of L, a, b. Coloured products were formed in reactions of simple phenols with nitrite while amino acids formed only slightly coloured products. An increase in beer colour after its reaction with nitrite is probably connected with the reaction of nitrite with polyphenolic compounds. The test for the determination of a contamination reducing nitrates in brewing yeast wos developed. During this test yeasts were cultivated in buffer (pH 5.0) with the addition of potassium nitrate and m-phenylenediamine.
(In Czech, English summary only)

Keywords: beer, colour, nitrites

Published: November 1, 1992