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Peanut oil contains large amount of non-polar lipids and minor polar lipids. However, the effect of roasting on lipid profile of peanut oil has not been investigated systematically. Herein, an UPLC-Q-Exactive Orbitrap mass spectrometry-based lipidomic method was applied to comprehensively analyze lipid profile of the oils from raw, light and dark roasted peanut kernels. Microstructure of peanut kernels, physicochemical properties and oxidized fatty acids in peanut oil during roasting were also evaluated. Dark roasting destructed the cell membrane severely according to microstructure observation. The color of the oils became darken after light and dark roasting. Acid value increased during roasting. Peroxide value, conjugated dienens, and oxidized fatty acids increased after light roasting while decreased after dark roasting. Roasting had an obvious effect on phospholipids. Triglycerides and diglycerides showed a thermal stability during this process. Our study could provide useful information for peanut oil processing. • Roasting had significant effect on lipids, especially fatty acids and phospholipids. • Light roasting increased OFAs, while dark roasting decreased their contents. • Lipids degradation and oxidation were the main behaviors during roasting. [ABSTRACT FROM AUTHOR]

To extend shelf-life and develop new bayberry products, the effects of storage time and temperature on polyphenolic content and qualitative characteristics of freeze-dried and spray-dried bayberry power were studied. Results showed that the retention of total polyphenols, gallic acid, protocatechuic acid, cyanidin-3-o-glucoside and anthocyanins in the freeze-dried bayberry powder was in most cases higher than in the spray-dried powder when they were stored for the same period. The content of these components in both the freeze-dried and spray-dried bayberry powder decreased gradually with the longer storage time. No significant difference was detected for the retention of these compounds whether they were stored at 4 °C or 25 °C. The browning index of both the freeze-dried and spray-dried powder significantly increased during a 50-day storage period. The ΔE value of the bayberry powder stored at 25 °C was distinctly higher than that of the other treated samples; a value of the spray-dried powder was slightly higher than that of the other samples. All presented results indicate that freeze-drying and 4 °C storage is an efficient and convenient method to maintain the bioactive polyphenolic components and high-qualitative characteristics of bayberry fruits. [ABSTRACT FROM AUTHOR]