Oligosaccharides in Soy Sauce

Automated analysis of oligosaccharides in soy sauce was performed according to gel filtration method with Biogel P-2 by using JLC-6 AH liquid chromatograph apparatus. As the results, mono-, di-, tri-, tetra-, and polysaccharides in soy sauce were separated. The contents of oligosaccharides in Koikuchi and Usukuchi shoyu, almost of which consisted of disaccharides, were about 0.5g/100ml. On the other hand, the contents of oligosaccharides in Tamari and Shiro shoyu, almost of which consisted of di-, tri-, and tetrasaccharides, were about 1.0 and 3.0g/100ml, respectively. In Koikuchi shoyu mash, there existed di-, tri-, and tetrasaccharides during first 20 days of aging. After stage of alcohol fermentation, the tri-, and tetrasaccharides almost disappeared from the mash. Each fraction separated by gel filtration was chromatographed on anion exchange resin with borate buffer. As the results, several peaks were detected in each chromatographic pattern. The sugar composition of the di-, and trisaccharide fractions were determined as glucose, galactose, arabinose, xylose and mannose. Among them, glucose was main component. The tetrasaccharide fraction from Tamari shoyu was composed of considerably amount of rhamnose. In the case of Shiro shoyu, tetrasaccharide fraction consisted of a lot of xylose and arabinose.