The Effect of Extraction Methods on the Components and Quality of Camellia Oleifera Oil: Focusing on the Flavor and Lipidomics

The objective of this study was to systematically elucidate the effects of conventional (Cold Pressing, CP; Hot Pressing, HP; Soxhlet Extraction; SE) and novel methods (Microwave -Assisted Extraction, MAE) on the physicochemical properties, bio-active substances, flavor and lipidomics of Camellia oleifera oil (COO). The coldpressed COO contained the highest contents of squalene (176.38 mg/kg), alpha-tocopherol (330.52 mg/kg), polyphenols (68.33 mg/kg) and phytosterols (2782.55 mg/kg). Oleic acid was observed as the predominant fatty acid with the content of approximately 80%. HS-GC-IMS identified 47 volatile compounds, including 11 aldehydes, 11 ketones, 11 alcohols, 2 acids, 8 esters, 2 pyrazines, 1 furan, and 1 thiophene. A total of 5 lipid classes and 30 lipid subclasses of 339 lipids were identifed, among which TGs and DGs were observed as the major lipids. In summary, both cold -pressed and microwave -assisted technologies provided high -quality COO with high content of bio-active substances and diglycerides/triglycerides.