title: Interactions of protein content and globulin subunit composition of soybean proteins in relation to tofu gel properties.
abstract: The content and globulin subunit composition of soybean proteins are known to affect tofu quality and food-grade soybeans usually have higher levels of proteins. We studied the tofu quality of soybeans with high (44.8%) or low (39.1%) protein content and with or without the 11S globulin polypeptide, 11SA4. Both protein content and 11SA4 significantly affected tofu gel properties. Soybeans containing more protein had smaller seeds which produced significantly firmer (0.663 vs.0.557 N, p<0.001) tofu gels with creamier colour. The absence of 11SA4 was positively correlated with seed size, tofu hardness and water holding capacity and led to significant changes to the profile of storage protein subunits, which may have contributed to the improvement in tofu gel properties. These results suggest that, in combination with higher protein content, certain protein subunits or their polypeptides can also be targeted in selecting soybeans to further improve soy food quality.
authors.affiliation: CSIRO Agriculture, 306 Carmody Road, St Lucia, Qld 4067, Australia.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: James
authors.affiliation: CSIRO Agriculture, 306 Carmody Road, St Lucia, Qld 4067, Australia. Electronic address: Aijun.Yang@csiro.au.
authors.forename: Aijun
authors.initials: A
authors.lastname: Yang
mesh_terms: D063427:Food Quality; D005916:Globulins / Q000032:analysis*; D006244:Hardness; D021122:Protein Subunits; D055314:Seed Storage Proteins / Q000032:analysis*; D012639:Seeds / Q000737:chemistry; D045730:Soy Foods / Q000032:analysis* / Q000592:standards; D030262:Soybean Proteins / Q000032:analysis* / Q000737:chemistry; D013025:Glycine max / Q000737:chemistry*
chemical_list: D005916:Globulins; D021122:Protein Subunits; D055314:Seed Storage Proteins; D030262:Soybean Proteins
keywords: Globulin subunits; Soybean protein content; Tofu gel quality