Enzymatic Synthesis and <i>in vitro</i> Digestion Characteristics of Human Milk Fat Substitutes 1,3-Dilinoleoyl-2-palmitoylglycerol

1,3-dilinoleoyl-2-palmitoylglycerol (LPL) is an important structural lipid in breast milk fat, which plays an important role in the health of infants, and therefore the development of an efficient method for the preparation of such compounds is necessary. In the present study, LPL was efficiently catalytically synthesized by immobilized lipase ANL-MARE as a biocatalyst using tripalmitate and linoleic acid in a solvent-free system, and its digestive properties were investigated. The optimal process conditions for the enzymatic acidolysis of LPL were optimized by response surface test: the molar ratio of PPP:LA was 1:10, the enzyme addition was 13.60%, the reaction temperature was 50℃, and the reaction time was 5 h. At this time, the relative content of LPL in the product was 67.78%, of which the relative content of sn-2 palmitic acid (sn-2 PA) accounted for 71.50%. In vitro gastrointestinal digestion of LPL resulted in the release of 59.69% of its fatty acids. The digested product contained higher levels of free unsaturated fatty acids and palmitic acid monoacylglycerols. In conclusion, the immobilized enzyme ANL-MARE has great potential to catalyze the preparation of LPL, which provides a new strategy and theoretical basis for the efficient preparation of human milk fat substitutes.