Physicochemical properties, antioxidant activity and phyto-nutritional composition of cold and hot pressed coconut oils

Abstract

Cold and hot pressed (CP and HP) coconut oils were subjected to physicochemical, antioxidant, fatty acid profile, vitamin composition and phytosterol analyses using standard analytical procedures. From the studies, both oils were soluble in non - polar solvent and liquid at room temperature. Hot pressed (HP) oil had a higher peroxide value, iodine value and saponification value while cold pressed oil had a higher free fatty acid and acid value. The antioxidant activity revealed that cold pressed oil had a better ferric reducing antioxidant potential (FRAP) and total antioxidant capacity (TAC) than the hot pressed oil. The major fatty acids (%) found in both oil extracts were lauric acid (49.29 and 47.83), myristic acid (17.01 and 16.33), palmitic acid (9.53 and 9.94), capric acid (6.39 and 7.72) and caprylic acid (5.45 and 5.77) for cold and hot pressed oils respectively. Hot pressed oil had higher phytosterol content (102.79 mg/100g) however, the major phytosterol in both oils were β-sitosterol, Δ-5-avenasterol and stigmasterol. Vitamins A, D, E and K were present in trace amount in both oil extracts. Hot pressed oil had a slightly better physicochemical characteristic and phyto-nutritional composition while cold pressed oil had a better antioxidant property. Considering the physicochemical properties, antioxidant activity and phyto-nutritional composition of cold and hot pressed coconut oils, their use in nutraceuticals and other industrial purposes should be encouraged.