PHYSICAL-PROPERTIES OF INTERESTERIFIED FAT BLENDS

Fat blends, formulated by mixing fully hydrogenated soybean oil with n ine different commonly used vegetable oils in a ratio of 1:1 (w/w), we re subjected to interesterification (also commonly referred to as rear rangement or randomization) with sodium methoxide catalyst. Fatty acid composition and triacylglycerol molecular species of each fat blend a nd the interesterified product were determined and correlated with the following physical properties: melting, crystallization characteristi cs and solid fat content. The differences in the endothermic and exoth ermic peak temperatures, total heat of fusion and crystallization (bet a and beta' crystalline content) and solid fat content among the fat b lends clearly showed the effect of the composition of each oil on the physical properties. Oils that contained a considerable amount of palm itic acid had a favorable influence on the crystallization and polymor phic form of interesterified fat blends.