@techreport{oai:iwate-u.repo.nii.ac.jp:00008935,
 author = {小野, 伴忠},
 month = {Mar},
 note = {科学研究費補助金[基盤研究C](課題番号09660125)研究成果報告書, 健康に必須である油をより美味に安定に食品へ導入するかを研究するために、大豆中の油が如何にして水中で安定な乳濁質を作り、豆腐ゲル中で強固に固定されているかをタンパク質と脂質の関係から研究した。

1. 大豆より未加熱の豆乳とそれを加熱した豆乳を調製し、超遠心分離によりクリ-ム,可溶性,粒子の3画分を得、タンパク質・脂質含量を測定した。未加熱では中性脂質の70%が粒子中に存在し、加熱によりそのほとんどがクリ-ム画分に移行することが判った。リン脂質は未加熱・加熱に関わらずその半量はタンパク質に結合していた。

2. 未加熱豆乳を室温から100℃近くまで5℃づつ順次温度を上昇させたものについて、1.同様に分画後、分析を行った。粒子中に含まれるタンパク質,脂質は65-70℃で粒子より遊離し、80-90℃で脂質はクリ-ム画分に、タンパク質は新たに11SのBと7Sのβサブユニットで粒子を形成することが判った。クリ-ム画分中タンパク質は中性域に等電点を持つオレオシン様タンパク質であることが分かった。

3. 豆乳に塩化カルシウムを順次加えると、先ずクリ-ム画分と粒子が結合し、その後に可溶性タンパク質がさらに結合して行くことが分かった。そのため、脂質はタンパク質に取り囲まれて豆腐カ-ドを作ると推定された。

以上のことから、豆乳脂質の安定化はオイルボディ類似のクリ-ム生成とそれが豆腐カ-ド形成における核として機能することによると考えられる。, Soymilk is prepared by heating swelled and ground soybeans, of which major components are lipid and protein. The stability of lipid in aqueous solution is important in soymilk. The interaction between lipid and protein in soymilk was studied from the viewpoint of changes in the lipid and protein distribution by healing, Soymilk was fractionated to particulate, soluble and floating fractions by centrifugation. Most of the lipid in unheated soymilk existed in particulate fraction. When beating from 65ﾟC to 75ﾟC, a part of lipid and almost alpha and alpha subunits of beta-conglycinin in the particulate fraction liberated and moved to soluble fraction. When heating at 75ﾟC, the lipids in the soluble and particulate fractions began to liberate and to shift to the floating fraction. Almost all lipid (neutral lipid) shifted to the floating fraction at 90ﾟC.The major protein in floating fraction was two unknown proteins (named BX_1 and BX_2). The BX_1 and BX_2 are minor proteins in soymilk and had relative molecular weights of 22,000 and 16,000, respectively

The lipid holding in the tofu (soybean curd) has such a stability as that it is not released even when it is cooked. The lipid in soymilk is incorporated into the tofu with coagulation of proteins on processing by the addition of a calcium salt The incorporation of lipid into the coagulum was examined from the association with protein. The lipid in soymilk was obtained as the floating fraction by centrifugation. The floating fraction decreased by the addition of calcium chloride prior to form a protein coagulum. When a half of the protein coagulated, the entire floating fraction became inseparable. The protein in soymilk then, was separated into particulate and soluble fractions by centrifugation. The decrease of the floating fraction with adding calcium chloride was parallel to the coagulation of the particulate protein. The association of the floating fraction and the soluble protein occurred after the new particles formed from the soluble proteins. These results indicated that the lipid incorporation took place by the conjugation of the lipid and protein particles.

These results suggest that the lipid is surrounded by particulate protein, connected like network each other, and become to core of tofu curd.},
 title = {豆乳クリームの生成とその安定性},
 year = {1999}
}