TY - JOUR T1 - Pigment Analysis in Red and Rosé Wines by Tristimulus Colorimetry JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 166 LP - 170 DO - 10.5344/ajev.1977.28.3.166 VL - 28 IS - 3 AU - Angela C. Little Y1 - 1977/01/01 UR - http://www.ajevonline.org/content/28/3/166.abstract N2 - The pigment composition of red and rosé wines was determined by tristimulus colorimetry using the thin-layer transreflectometric technique at two pH levels. The magnitude of change on acidification in chromaticity coordinates, expressed as (Δr2 + Δg2)1/2, and in blue transreflectance, expressed as Δ-log B, provide quantitative measures of pH-responsive anthocyanin pigment. The Δ-log B readings can be interpreted in terms of the contribution to total absorption by the pH-responsive and pH-non-responsive absorbing components. ER -