Properties of co-gel between Tenebrio Molitor larvae protein and myofibrillar protein induced by transglutaminase.

This study explored the effect of adding transglutaminase (TGase) to a co-gel of Tenebrio Molitor larvae protein (TMLP) and myofibrillar protein (MP). Different concentrations of TGase (0-90 U/g) were added to the co-gel. The results showed that 60 U/g TGase treatment significantly improved the gel strength and water holding capacity (WHC) by 26.51 g and 9.2 %, respectively. TGase promoted the rheological properties and accelerated the three-dimensional network structure of the co-gel. Moreover, TGase significantly increased (P < 0.05) the tyrosine residues, tryptophan residues content and hydrophobic interactions of the aliphatic groups. The chemical forces between the protein molecules changed. TGase promoted the transition of α-helix to ß-sheet and free water to immobilized water, thereby improving the WHC of co-gel. The principal component analysis reflected the links among indicators. This study illustrated that TGase might be an effective strategy to improve the co-gel of TMLP and MP and emulsified meat products with insects.

Effect of High-Voltage Electrostatic Field Heating on the Oxidative Stability of Duck Oils Containing Diacylglycerol.

High-voltage electrostatic field (HVEF) as an emerging green technology is just at the beginning of its use in meat products and by-products processing. In this study, we employed duck oil to produce duck-oil-based diacylglycerol (DAG), termed DDAG. Three different DDAG volume concentrations (0, 20%, and 100%) of hybrid duck oils, named 0%DDAG, 20%DDAG, and 100%DDAG, respectively, were used to investigate their thermal oxidation stability in high-voltage electrostatic field heating and ordinary heating at 180 ± 1 ℃. The results show that the content of saturated fatty acids and trans fatty acids of the three kinds of duck oils increased (p < 0.05), while that of polyunsaturated fatty acids decreased (p < 0.05) from 0 h to 8 h. After heating for 8 h, the low-field nuclear magnetic resonance showed that the transverse relaxation time (T21) of the three oils decreased (p < 0.05), while the peak area ratio (S21) was increased significantly (p < 0.05). The above results indicate that more oxidation products were generated with heating time. The peroxide value, the content of saturated fatty acids, and the S21 increased with more DAG in the duck oil, which suggested that the oxidation stability was likely negatively correlated with the DAG content. Moreover, the peroxide value, the content of saturated fatty acids and trans fatty acids, and the S21 of the three concentrations of duck oils were higher (p < 0.05) under ordinary heating than HVEF heating. It was concluded that HVEF could restrain the speed of the thermal oxidation reaction occurring in the duck oil heating and be applied in heating conditions.