六条大麦「カシマムギ」と「カシマゴール」を2年度にわたり４つの施肥条件で3反復ずつ栽培し, タンパク質含量の異なる原麦を得た. これらを焙煎し, 抽出した麦茶液に含まれる香気成分をGC-MSで分析し, 21成分の含量を測定した. 麦茶液中のピラジン類, チアゾール類とfuranylmethylpyrroleの濃度は原麦タンパク質含量と正の相関がみられ, furfuralの濃度は負の相関がみられた. 一方, 2-methylbutanal, 3-methylbutanal, hexanal, 4-ethyl-2-methoxyphenol, 2-methoxy-4-vinylphenolはタンパク質含量の差による影響はみられなかった. 原麦タンパク質含量はメイラード反応を経由して生成される香気成分の含量と組成に影響し, タンパク質含量が高いほど香ばしい, ナッツ様の香りが強くなり, 低いほどアーモンド様の甘い香りが強くなることが示唆された.

牛乳, および乳製品中の脂肪族アルデヒドの分析法の開発を行った. ppbレベルのヘキサナールを定量するために, 既報を参考に酢酸と1,3-シクロヘキサンジオンを用いたラベル化反応を行ったところ, 副生成物が発生し定量することが困難になった. この問題を解決するために, 酢酸をギ酸, クエン酸, 硫酸に変更したところ, 副生成物の発生を抑えることができた. 硫酸を用いたラベル化反応のバリデーションを牛乳, コーヒー入り乳飲料, ヨーグルトに対し行い, 精度良く分析できることを確認した. また, 牛乳に光照射により発生させたアルデヒド類の定量を行い, 精度良く分析することができた.

本分析法を用いて, 牛乳, および乳製品中の脂肪族アルデヒドの微量分析が行われることを期待する. また, 本報が既知の分析法を参考に微量分析を行う際に, 定量値に影響を与える物質がないかを確認するときの一助になれば幸いである.

The "Soybean" research workshop, held during the 2025 (72nd) Annual Meeting of the Japan Society for Food Science and Technology, focused on shifting the perspective of tofu research from traditional "manufacturing technology" to "process design" to explore its new potential. While tofu remains an indispensable part of Japanese food culture, the number of manufacturing facilities has declined to approximately 2,000, indicating a significant turning point for the industry. This structural change suggests an emerging new direction in tofu research. Under these circumstances, tofu should be re-evaluated not merely as a traditional product but as a protein gel material with well-defined structural and functional properties. A deeper understanding of soybean protein structure and coagulation behavior is indispensable for linking molecular-level insights to rational process design. This workshop discussed recent advances in molecular analyses of tofu coagulation mechanisms and their potential applications. Redefining tofu through materials science and treating it as a subject for structural design is expected to not only advance soybean processing research but also contribute to the creation of new food value and the expanded utilization of domestic soybeans.

Tofu, a traditional Japanese food, has great potential as a base material for developing new food products. The author re-examined the molecular mechanism of tofu coagulation and developed several new plant-based foods using advanced tofu-processing technology. The key mechanism underlying tofu formation was identified as the neutralization of protein surface charges, enabling protein molecules to come into close proximity and aggregate. In addition, the author developed several new products such as iron-fortified tofu, tofun, tofu pudding, tofu cream, and tofu ink. Tofun is a commercial dessert prepared by aggregating soymilk proteins using honey. Tofu pudding, created by solidifying a mixture of soymilk and sugar with glucono-delta-lactone, is suitable for vegans, individuals with egg or dairy allergies, and those with dysphagia. Tofu cream serves as a vegan substitute for custard cream and is appropriate for patients with egg, dairy, and wheat allergies. Tofu inks have been developed by mixing tofu with other food-grade ingredients, demonstrating its versatility as an edible material. The author hopes this report will serve as a catalyst for developing a wide variety of new tofu-based food products.