Effects of Microorganisms during Aging on Quality of "Kaeshi" for "Sobatsuyu", Japanese Noodle Soup

Studies on Utilization Techniques of Soy Sauce in Food Processing, Part 2

Abstract

"Sobatsuyu"(Japanese noodle soup) is prepared by mixing "Kaeshi"(mixture of soy sauce, sugar and Mirin) and a extract of dried bonito. The influences of growth of microorganisms on the quality of "Kaeshi" were investigated."Kaeshi" inoculated with various microorganisms were incubated for several days at 30°C. Viable cell counts of Pediococus halophilus and Aspergillus oryzae decreased and those of Lactobacilus spp. remained approximately constant during incubation. On the other hand, the counts of Zygosaccharomyces rouxii and Z. rouxii (film-forming) increased with incubation time. With the growth of Z. rouxii, the sugar contents of "Kaeshi" decreased, but the alcohol contents increased. By sensory analysis, the growth of Z. rouxii had no effect on the quality of "Kaeshi", but Z. rouxii (film-forming) gave a bad effect.