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.

[The quality of Salvia miltforthiza from Beijing suburbs with different growing modes].

OBJECTIVE: Study the yield and quality of Salvia miltforthiza in the poplars and apple trees intercropping system. METHODS: Assay the yield, heavy metals, organochlorine pesticides and active components of Salvia miltforthiza in different intercropping systems are different. RESULTS: The contents of Cd exceeds the allowed figure seriously though other heavy metals such as Pb, As, Hg, Cu fell in the standard range. The contents of organochlorine pesticides of different Salvia miltforthiza fell in the standard range. The active components of biennial Salvia miltforthiza intercropping with apple trees, including Tanshinone II A and Salvianolic acid B complied with the quality standards of Pharmacopoeia. CONCLUSION: Soil fertility, heavy metals of intercropping system and planting years should be considered in order to ensure the quality and stability of Chinese medicine.