Analysis of Physicochemical Properties, Lipid Composition, and Oxidative Stability of Cashew Nut Kernel Oil
Yijun Liu, Leshi Li, Qiuyu Xia, Lijing Lin
Abstract
Cashew nut kernel oil (CNKO) is an important oil source from tropical crops. The lipid species, composition, and relative content of CNKO were revealed using ultra high performance liquid chromatography time-of-flight tandem mass spectrometry (UPLC-TOF-MS/MS), and the physicochemical properties, functional group structure, and oxidation stability of CNKO at different pressing temperatures were characterized using a near infrared analyzer and other methods. The results showed that CNKO mainly consisted of oleic acid (60.87 ± 0.06%), linoleic acid (17.33 ± 0.28%), stearic acid (10.93 ± 0.31%), and palmitic acid (9.85 ± 0.04%), and a highly unsaturated fatty acid (78.46 ± 0.35%). In addition, 141 lipids, including 102 glycerides and 39 phospholipids, were identified in CNKO. The pressing temperature had a significant effect on the physicochemical properties of cashew kernels, such as acid value, iodine value, and peroxide value, but the change in value was small. The increase in pressing temperature did not lead to changes in the functional group structure of CNKO, but decreased the induction time of CNKO, resulting in a decrease in their oxidative stability. It provided basic data support to guide subsequent cashew kernel processing, quality evaluation, and functional studies.