Effect of interesterification catalyzed by glycerol-K2CO3 deep eutectic solvents on the physicochemical properties of lard

Abstract

Modified lards were prepared through interesterification catalyzed by glycerol:K2CO3-based deep eutectic solvents. The physicochemical properties of these lards with various interesterification degrees (IDs) were determined for investigating the effects of IDs on their physicochemical characteristics. Fatty acid (FA) compositions of the modified lards were almost unchanged, however FA composition at sn-2 position significantly changed with IDs increasing. As IDs increased, Free FAs and monoacylglycerols in modified lards increased slightly, diacylglycerols raised, and triacylglycerols decreased; among triacylglycerols, trisaturated triacylglycerols and triunsaturated triacylglycerols increased gradually. Compared with original lard, modified lards had relatively flatter solid fat content curves. Modified lards with higher IDs (over 50%) had higher slip melting points and distinctive thermal property. The polymorphism of lards transformed from β to β′-form with IDs increasing, but the stacking pattern of crystals was unchanged. The micromorphology of interesterified lards was much finer indicating that the sandiness of original lard was modified after interesterification. The crystallization behaviors of modified lards at 20 °C were affected by IDs, which was distinctly different from that of original lard. The interesterified lards with higher IDs (over 50%) were more suitable as shortenings in comparison with the original lard.