Physical properties of structured lipids from lard and soybean oil

Human milk fat is essential for the development of term infants. The fatty acid composition and distribution in the triacylglycerols chains must be object of studies in infant formulas. The objective of this paper was to obtain structured lipids that have similar characteristics to the human milk fat. Binary mixtures of lard and soybean oil in different ratios (80:20, 60:40, 50:50, 40:60, 20:80) were submitted to chemical interesterification. The fatty acid composition, acid value, iodine value, solid fat content, consistency and melting point were analyzed in the mixtures before and after the interesterification. The solid fat content and consistency of lard decreased by the addition of soybean oil. Chemical interesterification modified the behavior the binary mixtures of lard with soybean oil, in all ratios, possibly as a function of the increase of di and trisatured triacylglycerols produced by the randomic effect. The interactions between lard and soybean oil presented a monotectic effect before and after the chemical interesterification. The modified mixtures with 20 and 40% of soybean oil presented similar fatty acid composition to human milk fat.