Ethanol is added to prevent re-fermentation of yeast in miso that is not heat-sterilized, but this increases manufacturing costs. In response to a request from the Hiroshima Prefecture Miso Cooperative to reduce the amount of ethanol used, we developed the yeast DBH114 strain for miso manufacturing. Mutant strains were obtained from the 　D-9 strain used in the Cooperative. The DBH114 strain was selected by assessing its ethanol sensitivity and ethanol production ability in liquid cultures. In a small-scale miso manufacturing test (total weight of 2 kg), it was confirmed that the DBH114 strain produced an amount of ethanol equivalent to that of the D-9 strain and met the target of easy breakdown. In miso manufacturing with a total weight of 1,000 kg, the DBH114 strain suppressed re-fermentation at a lower ethanol concentration than the D-9 strain, indicating the possibility of reducing the amount of ethanol added.

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When plant foodstuffs were softened by freeze-thaw impregnation with macerating enzymes, it was often a problem that sourness was generated with the softening. In this study, we investigated the change over time in firmness and galacturonic acid content due to enzymatic reactions in burdock roots. As a result, more than 50% of the change in firmness occurred within 24 hours, but the galacturonic acid was produced in large amounts after 24 hours. A high correlation was observed between the pH value of burdock roots and the galacturonic acid included therein, indicating that the production of galacturonic acid during the enzymatic reaction process was one cause of the sourness. The results suggested that the promotion of softening using the enzymes with a citric acid-sodium citrate buffer can suppress excessive production of galacturonic acid and reduce the sourness.

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Aiming to create a new confectionery produced locally for local consumption using a by-product of Hiroshima Prefecture (azuki bean skins), we developed processing technologies such as creating paste and creating powder, and evaluated the suitability thereof as a confectionery ingredient. For the conversion of azuki bean skins into a confectionery ingredient, we investigated the particle size and physical properties of the crushed azuki bean skins through wet milling tests to confirm the suitability thereof as a confectionery ingredient, and then examined conversion into powder and paste. The functionality of azuki bean skins was evaluated, and the results showed that approximately 600 mg of polyphenol was contained per 100 g of powder, suggesting the possibility of added value when used in confectioneries. An efficient processing method was devised to grind the bean skins after drying instead of wet grinding, and equipment was introduced to a company. As a result, high-quality powder with a stable particle size was obtained, and the technology transfer to the company factory was completed.

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