Enzymatic conversion of Camellia Seed Oil to glycerol esters: synthesis, characterization, and mechanism analysis

The conversion of triglycerides in edible oils into diacylglycerols (DAGs) is of great significance for a healthy lifestyle. Camellia Seed Oil (C-oil), which is rich in oleic acid and linoleic acid, is an excellent raw material for the production of DAG. In this study, the results showed that under the optimum conditions, the hydrolysis rate was 87.14 %, and the content of DAG was 62.49 % after the hydrolysis product was esterified with glycerol. The C-oil, C-FFA, and Camellia Seed Oil diacylglycerol (C-DAG) were characterized using GC, TG, DSC, and GC-IMS. The results showed that the enzymatic coupling method did not affect the structural composition of the substances themselves, but it did affect the crystallization and melting properties of the oils and the taste of C-DAG was more delicate than that of C-oil. Finally, the reaction mechanism was analyzed using infrared spectroscopy, which showed that C-oil had been mostly hydrolyzed into free fatty acids, and C-DAG exhibited ester C-O stretching vibrations at 1280-1030 cm-1, indicated that the esterification reaction between C-FFA and glycerol had successfully occurred under the catalysis of the enzyme.