The Effect of Chemical Intersterification of Palm Stearin and Canola on Physicochemical Characteristics of Produced Product

The adverse effects of trans fatty acids on health during hydrogenation demands trans free products. Trans interesterification might be considered a process to solve this problem. The aim of this study is to interesterify palm stearin and canola to provide a hardened media and then investigate the physicochemical characteristics of the product. Binary blends of palm stearin/canola oil (in ratios of 10:90, 20:80, 30:70, 40:60 and 50:50 w/w) were interesterified using sodium methoxide as an alkaline catalyst. The changes in fatty acid composition, the 2-position arrangements of fatty acids, free fatty acids content, peroxide value, soap content, induction period at 120 °C (IP120), slip melting point (SMP) and solid fat content (SFC) of fat blends, before and after interesterification, were investigated. Studies on fatty acid composition before and after interesterification showed that the process did not affect the chemical structure of fatty acid and the concentration of trans. All blends were trans-free and contained high essential fatty acids contents. Studies concerned with the 2-position arrangements of fatty acids, have shown that the expected random equilibrium has been achieved after 60 min of processing. Interesterification has modified the melting properties of fat blends by decreasing SMP and SFC. Interesterification has modified the melting properties of fat blends by decreasing SMP and SFC. Interesterified blends of palm stearin/canola oil at the ratio of 10:90 for liquid margarine, 20:80 and 30:70 for soft tub margarine, 30:70 and 40:60 for Iranian vanaspati and 50:50 for ice-cream formulation showed desirable characteristics.