Studies on Changes in the Color and Flavor of Sake Caused by Exposure to Light and Storage (XIV) Components of Sake contribute to Color Developement during Storage

Abstract

Components of sake which contribute to color development during storage were studied.
By one method, the relation between the components of sake and color development during storage were statistically examined, and by another method sake was separated into five fractions with ionexchange resins, and the effectiveness of each fraction on color development was studied.
1. Color development caused by storage was correlated positively to amino acidity, acid and alkaline buffer actions, optical densities at 270mμ, 320mμ and 420mμ of sake before storage, and to increasing amounts by storoge of N-D-glucosides or its Amadori rearrangement products, of 3-deoxyglucosone, and was also correlated positvely to contents of Zn, of deferri-ferrichrome, of ferulic acid and of flavin which seemed to be substituted components.
2. Of the five fractions, the neutral- or acid-nitrogen fraction (R fraction) had the strongest effect on color development during storage.3. With the addition of sodium bisulfite to sake, intermediates in coloring reaction were accumulated into R fraction during storage.
4. N-D-glucosides or its Amadori rearrangement products were presumed to be one of the intermediates in the coloring reaction of sake.