High molecular weight glutenin subunits (HMW-GSs) are among the most critical determinants of wheat processing quality, which are responsible for the formation of glutenin polymeric structures via interchain disulfide bonds. We identified a new HMW-GS Dy10 allele (Dy10-m619SN) by using EMS. The amino acid substitution (serine-to-asparagine) encoded in Dy10-m619SN allele resulted in a partial post-translational cleavage by vacuolar processing enzymes. This cleavage produced two new peptides, which disrupted the interactions among gluten proteins because of the associated changes to the number of available cysteine residues for interchain disulfide bonds. Consequently, Dy10-m619SN expression decreased the size of glutenin polymers and weakened glutens, which resulted in wheat dough with improved cookie-making quality, without changes to the glutenin-to-gliadin ratio. Clarification of the underlying mechanisms on this post-translational cleavage is ongoing.

Xm-60453

Effects of steam explosion on the nutritional and functional properties of black-grained wheat bran and its application

Yuxiu Liu1, Shuhua Wang2, Tianqi Meng1, Yizhao Wang1, Zhengmao Zhang1

1College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi, China

2Hybrid Rapeseed Research Center of Shaanxi Province, Yangling 712100, Shaanxi, China

In recent years, an increasing interest in healthy functional foods has been documented among health-conscious consumers. Steam explosion (SE)-treated black-grained wheat (BGW) bran was explored for the development of chiffon cakes with high nutritional and functional value. The results indicate SE at 0.6-1.0 MPa effectively reduced the crude fat and total starch content, as well as increased the Fe, Mn, and Se content, soluble dietary fiber (SDF) content, water-holding capacity (WHC), oil-binding capacity, swelling capacity, cholesterol binding capacity, cation-exchange capacity, total polyphenols content, DPPH radical scavenging activity, and hydroxyl radical OH− scavenging ability of wheat bran. The content of crude fat and total starch decreased with increasing SE pressure, while WHC and antioxidant activity had the opposite trend. The nutrition and functional properties of SE BGW bran were better than that of SE white-grained wheat (WGW) bran. The addition of SE wheat bran (0.8 MPa) to flour significantly decreased the peak viscosity, final viscosity and setback, as well as increased the pasting temperature. The effect of SE bran on the pasting properties of wheat flour (low-gluten and middle-gluten) was stronger than that of high-gluten flour. Similar results were also observed between the flour-SE BGW bran and SE WGW bran mixture. Chiffon cakes made with 2-10% SE BGW bran had enhanced antioxidant activity. When 6% SE BGW bran (0.8 MPa) was added, chiffon cakes exhibited good specific volume, hardness, chewiness, and other sensory qualities. Thus, SE at 0.6-1.0 MPa is an effective technique for enhancing the nutritional and functional properties of wheat bran. SE wheat bran (0.8 MPa) promoted the pasting properties of flour, and the addition of SE BGW bran improved the physicochemical properties of chiffon cakes. This study provides a technical foundation for the development of high-nutrition functional foods. SE BGW bran can be alternatives to food materials for developing health functional food products.