Syneresis Of Mizu-yokan (Soft Bean Jam Jelly) by Bacillus spp.

Abstract

Physicochemical and microbiological investigation for syneresis of Mizu-yokan (Soft bean jam) revealed the conversion of saccharide in the components by a specific bacteria, Bacillus subtilis etc.; Mizu-yokan with syneresis over 30% was accompanied by the increases of glucose, fructose, maltose and maltotriose, and the formation of levan from sucrose in the components. These phenomena were also observed in the Mizu-yokan-inoculated cells of Bacillus spp. isolated from the spoiled samples, or in jam added to culture broth from which bacterial cells had been excluded by membrane filter, suggesting that the marked syneresis of Mizu-yokan derives from the action of Bacillus spp., bacteria in the raw materials.