COLOUR DETERMINATION OF BEER USING TRISTIMULUS VALUES

Abstract

The derivation off tristimulus and chromaticity values for beers, using transmission measurements, is discussed. Chromaticity values indicate that the majority of beers have colours which resemble those represented by the EBC colour scale. However, the dilution of dark beers for colour analysis, according to Recommended Methods, leads to non‐standard colours. The colour adjustment of beers, using colouring agents, can also produce colours which deviate markedly from the standard EBC colour range. On this basis, the adoption of tristimulus measurement for quantification of beer colour is proposed. A method for obtaining tristimulus values of beers, based on transmission measurements at 5, 6 or 7 wavelengths, gives results comparing favourably with those from standard procedure, which requires transmission measurements at 5 nm, 10 nm or 20 nm intervals across the entire visible spectrum. 1992 The Institute of Brewing & Distilling