Interesterified coconut oil blends with groundnut oil or olive oil exhibit greater hypocholesterolemic effects compared with their respective physical blends in rats

Abstract

Blended oils consisting of coconut oil (CO) with groundnut oil (GNO) or CO with olive oil (OLO) were prepared to contain balanced amounts of saturated to unsaturated fatty acids. Blended oils were subjected to interesterification reactions catalyzed by IM-60 lipase from Rhizomucor miehei. Weanling rats were fed with native, blend, and interesterified oils at 10% level for 60 days. Serum cholesterol levels were lowered by 6% and 13%, respectively, in rats given blended oils containing CO/GNO and CO/OLO in comparison with rats fed with CO. Serum cholesterol levels were found to be reduced by 27% and 25%, respectively, when these blended oils were subjected to interesterification reactions and fed to rats. Similarly the liver cholesterol levels were decreased by 11% and 21%, respectively, when rats were given CO/GNO blends and interesterified oils compared with those given CO. Cholesterol levels in liver of rats given blend and interesterified oils of CO/OLO were reduced by 3% and 32%, respectively, as compared with that in rats given CO alone. These studies indicated that interesterified oils of CO with GNO or with OLO are more efficient in lowering cholesterol levels in rats compared with physical blends of CO with GNO or OLO. Therefore, although the physical blends had similar fatty acid compositions as that of interesterified oils, the hypocholesterolemic effects of interesterified oils were significantly greater than that which could be obtained from oils prepared by simple blending.