Effect of novel radio frequency roasting on color appearance, volatile compounds, fatty acid composition, and storage stability of peanut oil

Abstract

This study investigates the influences of RF roasting on oil yield, color appearance, bioactive components, antioxidant capacity, volatile compounds, sensory and nutritional properties, and storage stability of peanut oil under different target temperatures (140–170 °C), holding times (0–22.5 min), and moisture contents (8.29 % and 20 %). With increasing target temperature and holding time, the browning degree, total phenolics, antioxidant capacity, and characteristic flavor compounds (mainly pyrazines, aldehydes, and furans) of oil were significantly increased. The light-roasted oils showed the highest sensory scores on overall acceptability, while the dark-roasted oils presented stronger roasted and burnt odors. Increasing moisture content enriched 13 species and 34.43 μg/g of volatiles by promoting the Maillard reaction. Compared with hot-air roasting, RF roasting improved the oil yield and oil quality uniformity. A quality prediction method was developed based on the browning index. These findings indicated that RF roasting is a promising technique for processing high-quality plant oils.