Enzymatic preparation and quality evaluation of diacylglycerol-rich Swida wilsoniana fruit oil

Herein, diacylglycerol (DAG) was prepared from Swida wilsoniana fruit oil by a two-step enzymatic process, and the quality of crude Swida wilsoniana fruit oil (Crude oil), refined Swida wilsoniana fruit oil (Refined oil), DAG oil derived from crude oil (Crude oil-DAG), and DAG oil derived from refined oil (Refined oil-DAG) were compared and evaluated. The results showed that Lipozyme® RM IM enzyme exhibited the best hydrolysis effect in the hydrolysis reaction, while Novozym® 435 enzyme had a lower reaction energy barrier and a faster esterification catalytic rate in the esterification reaction, yielding a DAG content of up to 72.99%. Quality analysis showed that the physical and chemical indicators of the four oils all met the national standards, refining and enzymatic reactions can affect the tocopherol content, oxidative stability and flavor components of oils. The tocopherol content and oxidative stability in the crude oil were the best, and the volatile flavor substances of the crude oil and its DAG were richer. The research confirmed that the crude Swida wilsoniana fruit oil is an ideal raw material for the preparation of DAG, and the obtained DAG has excellent comprehensive quality. • Optimization of the enzymatic preparation process of diglyceride-rich Swida wilsoniana fruit oil. • DAG 36:4 (C 39 H 68 O 5 ) and DAG 36:3 (C 39 H 70 O 5 ) account for 98% of the diglyceride content. • Crude oil and Crude oil-DAG are rich in tocopherol and have better oxidative stability. • Crude oil and Crude oil-DAG are rich in volatile flavor compounds (40 species). • Refining reduces the content of tocopherols and flavor compounds.