RESUMO
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 â. 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.
RESUMO
The effects of unheated, 80 °C, 100 °C, and 121 °C on the physicochemical and microstructural properties of myofibrillary protein (MP) supplemented with glucose (Glc) and cellulose nanofibers (CNFs) were studied. The results showed that Glc and CNFs cross-linked with MP through non-covalent bonds when unheated compared with the unheated MP group, which increased the particle size and surface hydrophobicity of MP, and changed the secondary structure. At 80 °C and 100 °C, the particle size and hydrophobicity of MP significantly increased. At 121 °C, the contents of leucine and lysine in MP decreased by 16.2% and 19.9%, respectively, however, both Glc and CNFs could prevent this decrease. Meanwhile, microscopic images showed that the dispersion of Glc-MP and CNFs-MP were more uniform than the MP groups. Compared with Glc-MP, CNFs-MP had more uniform particle size distribution and better thermal stability at high temperatures (121 °C).
