Effects of konjac glucomannan on heat-induced changes of wheat gluten structure

Abstract

Effects of konjac glucomannan on the structure of wheat gluten were investigated at variable temperatures in this study. Dynamic oscillatory rheology study showed that konjac glucomannan conferred stiffness on gluten with a higher tan δ data at 25°C and 55°C, but this parameter was lower at 75°C and 95°C. Konjac glucomannan decreased the content of thiol equivalent groups and increased the α-helix/β-sheet content ratio, respectively. The thicker layer of gluten protein with 5% konjac glucomannan was observed by scanning electron microscopy. This study revealed that konjac glucomannan could alter the conformations of gluten proteins upon heating via non-covalent interactions and physical entanglements. It is likely that konjac glucomannan promotes protein aggregation by strengthening hydrophobic interaction at 25°C and 55°C, and alleviates heat-induced denaturation by decreasing the flexibility of polypeptide chain at higher 75°C and 95°C.

Texturisation behaviour of peanut–soy bean/wheat protein mixtures during high moisture extrusion cooking

“…The WG had better hydration capacity to form a dough with higher viscosity, which could prevent the flowing of melt during extrusion leading to a lower mass flow rate (Wang et al, 2017). So that the SME was increased significantly when blending PPP with WG (P < 0.05).…”

“…Particularly, it increased from 836.40 to 881.82 kJ kg À1 (P < 0.05) when the ratio of WG increased from 20% to 60%, which might be due to the viscosity increased and screw wear brought by the WG (Zarzycki et al, 2015). The increase in the viscosity also indicated that higher degree of aggregation might occur in the PPP-WG mixtures, which could entrap more water due to the greater effective volume of the aggregates (Zhang et al, 2016a;Wang et al, 2017).…”

Effects of simulated gastrointestinal digestion on the physicochemical properties, erythrocyte haemolysis inhibitory ability and chemical antioxidant activity of mulberry leaf protein and its hydrolysates

“…When compared with intact MP and HMP, the most obvious change in C2 was the decrease of b-sheets and the increase of b-turns (1678 and 1692 cm À1 ). Wang et al (2017b) also reported that the heat treatment of wheat gluten caused a decrease in bsheets. When compared the spectra of GHMP and GMP with that of C2, there were two bands at 1678 and 1692 cm À1 were shifted to 1682 and 1694 cm À1 , respectively, and a new band at 1650 cm À1 appeared.…”

Effect of baked wheat germ on gluten protein network in steamed bread dough

“…Compared to the control, the content of b-turn was slightly increased with BWG supplementation. These b-turns can be formed from b-sheets (Wang et al, 2017). The b-turn structure is considered as an open reverse turn, resulting in fewer hydrogen bonds was required to bond b-sheet structure than the multi-hydrogen (Tatham et al, 1985).…”