Frying characteristics of high‐oleic rapeseed blended oil: A comparative study

Abstract

The objective of this study was to identify the most suitable high‐oleic rapeseed blended oil for frying. Six high‐oleic rapeseed blended oils were formulated based on a polyunsaturated fatty acid/saturated fatty acid ratio of 2.0 and an n‐3 fatty acid/n‐6 fatty acid ratio of 1:4–1:6, after which the physiochemical properties, frying performance, tocopherol content, and hazardous substance contents were evaluated. The blended oil containing high‐oleic rapeseed oil: soybean oil: palm oil (85:12:3) had a reasonable fatty acid composition, better oxidative stability index (9.05 h), higher total tocopherol content (0.3 mg/kg), and longer time to reach a total polar component content of 27% (29.3 h). Moreover, after frying for 30 h, the peroxide value (7.25 mmol/kg), residual oil rate (0.57%), trans‐fatty acid content (0.37%), malondialdehyde content (1.57 μg/kg), and 3‐monochloro‐1,2‐propanediol ester content (0.24 mg/kg) were lower than those of the other samples. Principal component analysis revealed that the quality of the high‐oleic rapeseed blended oil was positively correlated with benzo[a]pyrene, 18:2, and 18:3, and negatively correlated with the residual oil rate, trans‐fatty acids, and 18:1 content. This high‐oleic rapeseed blended oil is potentially suitable for frying.