酒類の製造は安全醸造のために低pHで発酵させることが行われている。焼酎においては焼酎麹菌が多量のクエン酸を分泌し, それでpHが下がるが, 発酵のためには焼酎麹菌の生産する糖質分解酵素が低pHにおいて安定に機能し, 発酵性糖類が十分に供給される必要がある。焼酎白麹菌Aspergillus kawachiiの生産するキシラナーゼは好酸性・耐酸性を有することが報告されているが, その分子メカニズムについては分かっていなかった。
筆者らによって白麹菌キシラナーゼの好酸性・耐酸性機構がX線結晶構造解析によって分子レベルで解析され, その機構が明らかにされた。本稿では, 白麹菌のキシラナーゼのうち最も好酸性・耐酸性のキシラナーゼCについて, その特異な性質の獲得機構について解説していただいた。今後, 同様な性質を持つ他の酵素についても解析され, さらに明らかになると期待される。

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大豆種子とくに胚軸に含まれるイソフラボンは, 最近, 世界的に最も注目されている食品の成分の一つである。特に, がん, 骨粗霧症, 心臓疾患などの予防, 更年期障害の軽減に有効であることが明らかになってきた。
長年, 味噌のイソフラボンの研究に携わって来られた著者に, 原料大豆から, 味噌醸造中の同成分の消長, 体内での作用機講等について, 詳細に解説していただいた。

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醸造物を清澄化する方法としては, 珪藻土を濾過助剤として行う方法が最も一般的である。しかし, その裏で使用済珪藻土の廃棄物処理の問題が大きくクローズアップされている。
筆者は各種の清澄化技術と使用済み珪藻土を洗浄・焼成等により再利用する方法を構築した。それら珪藻土濾過システム全般について解説して頂いた。

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The post-distillation slurry made during shochu production is frequently discarded into the sea, however, it will have to be treated at facilities on land within 2 years. To reduce the amount of slurry, we improved a method of rice shochu production that separates the supernatant from the post-distillation slurry by centrifugation (2500 G, 10 minutes). The supernatant is then used instead of water in the second-stage fermentation of next batch.
The amount of post-distillation slurry derived from moromi (62 L) was 34.6 L, and this was separated into the supernatant (26.9 L) and solid component (7.7 kg). Although shochu production was repeated a total of eight times, the yield of alcohol in the 2-8 th production batches was always greater than the first batch (1.021-1.053 times). The fermentation time of the 2-8 th production batches was shorter than the first batch, possibly due to the increase in glucose-forming activity. We obtained a reduction of 68 percent in the amount of the post-distillation slurry.The concentration of diacetyl in the rice shochu, which was used as a chemical marker for quality (vacuum type), was only 50 percent of the critical detection level by humans, despite the fact that diacetyl increased when production was repeated. Although the componentratio of the flavor compounds was altered as a result of repeated production, sensory evaluation showed that the flavor-quality had not changed significantly.

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Kona-koji was prepared without the addition of a koji starter (Tanc-koji) for the production of Imo-shochu. The spores of molds carried in the air affected growth during the preparation of koji. So, we isolated the spores of molds from the vicinity of the places used for the preparation of koji and production of shochu.
As shown by the results, a 103 order of colonies per gram·koji of A. oryzae were isolated from kojimuro solids, shochu distillery solids and from the leaves of N. antiqua that are used to wrap the koji A. oryzae spores were also isolated from the air of the koji-muro and shochu distillery. In addition spores of A. niger and other molds were also isolated.
We measured the enzyme activity of these strains and investigated their physiological characteristics. Their acidity was higher than that of the standard strains. The characteristics of these strains agreed with those of strains isolated from kona-koji. Therefore, we found that spores of Aspergillus sp. were mixed with the raw material for koji from the leaves of N. antiqua or airborne spores, and these spores grew during the preparation of koji.
Further more, spores of other mold contaminating koji were isolated from the leaves of N. antiqua, but they were not detected in the koji. We found that their mold were selected against as the temperature of koji rose to 40C during its preparation.

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