Improvement of palm oil and sunflower oil blends by enzymatic interestrification

P>Palm oil (PO) and sunflower oil (SFO) blends with varying proportions were subjected to enzymatic interesterification (EIE) using a 1,3-specific immobilised lipase. The interesterified blends were evaluated for their slip melting point (SMP), solid fat content (SFC) at 10-40 degrees C, p-anisidine value, peroxide value, free fatty acids (FFA), induction period of oxidation at 110 degrees C (IP110) and composition of fatty acids by gas chromatography. Under EIE treatment, the blends of PO and SFO in different proportions (20:80, 40:60, 50:50, 60:40 and 80:20) had saturated and unsaturated fatty acid content in the range of 37.6-52.0% and 48.0-62.4%, respectively. The blends showed a considerable reduction in their SFC, SMP, peroxide value and oxidative stability at 110 degrees C, but presented increase in FFA and p-anisidine value. The optimum condition for minimising the fatty acid in oil was obtained, at 64 degrees C, using 8.9% enzyme and 3 h reaction time.