Abstract
Two-step extraction of sesame meal with 2% NaCl and 10% NaCl solution gave a preparation Extract II, which mainly consisted of 13S globulin. Conditions for gelation of Extract II were investigated and compared with those of soybean protein. An alkaline condition from pH 10 to ll.5 was necessary for gelation of Extract II. In protein concentrations higher than 2% in 2_??_7% NaCl solution, gels were formed after 2 min at 70°C. In a neutral pH range, sesame Extract II did not form gel. In contrast to that, soybean cold insoluble fraction (CIF) formed gel at pH 7, in 2% NaCl solution and in higher protein concentration than 9% after 30 min at 90°C. Gelation of the mixtures of Extract II and CIF was examined. At pH 7, a 3:1 mixture of CIF and Extract II formed gel but a 2:1 mixture did not. At pH 10, a significant and sudden rise of the critical gelling concentration was observed at a ratio of 2:3 of CIF and Extract II. Increase of viscosity prior to gelation of Extract II was not observed. Above 16 to 17% the gels were firm and selfsupporting, but drained fairly easily. These findings suggested the hydrophobic properties of the sesame gel.
