The Color of Miso

Abstract

Water soluble browing materials in the color of miso have been studied by comparing with those of shoyu. Eight color components were fractionated from the color of miso by DEAE-cellulose column chromatography (designated as P 1, P 2, P 3, P 4, P 5, P 6, P 7 and P 8 in the order of elution, respectively). The molecular weights of color components estimated with Sephadex G-25 and G-50 using color components of melanoidin from glycine-xylose system as standard substance were P 1=700, P 2=1200, P 3=1400, P 4=1800, P 5=2500, P 6=2700, P 7=4000, P 8=4700, respectively.
Color components of miso were separated by utilizing their conversion of elution position on DEAE-cellulose under oxidative environment. Color tone of color component separated became darker and ^1%_1cmE₄₅₀ value became higher with increasing degree of molecular weight. While, linear relationship between log ^1%_1cmE₄₅₀ and Kd was observed in the color components of miso. Moreover, the relationship between log ^1%_1cmE₄₅₀ and log molecular weight was found to be linear. Therefore, the equation, E=k×M^α (E: color intensity, M: molecular weight, k, α: constant), introduced from melanoidin produced from model system was fairly applicable to the color of miso. The equation, E=4.57×10^-4×M^1.32, was calculated in the color of miso. From these results, it was found that the properties of color of miso were almost similar to those of color of shoyu.
On the basis of their α value, formation of color in shoyu and miso was also discussed.