Partial interesterification of vegetable oils for production of trans-free fat

Interesterification modifies the physicochemical properties of fats by altering the triacylglycerol composition. The aim of this research was to apply partial enzymatic interesterification in trans-free fat production. Two formulations including binary blend of fully hydrogenated soybean oil and canola oil (19:81 ratio) or ternary blend of fully hydrogenated soybean oil, sunflower oil and canola oil (17.5:25:57.5 ratio) were interesterified by using the commercial lipase Lipozyme TL IM. Changes in physical properties were evaluated during 6 hours of reaction. As the initial oils used in the formulation were trans-free, the obtained products were also trans-free. Interesterification caused a decrease in melting point and solid fat content (SFC). After 5 hours of reaction, the chemical composition of fats reached to the equilibrium, so the physical properties of fats remained unchanged. Fully enzymatically interesterified fats had melting points similar to chemically interesterified ones. However, fully enzymatically interesterified fats had higher SFC at 10-30 °C than chemically interesterified ones. Comparison of physical properties of trans-free fats with typical properties of margarines and shortenings showed that trans-free fats from partial or full enzymatic or chemical interesterification can be used in production of baker’s margarine, soft tub margarine or vanaspati (household consumption oil).