Quality assessment of crude and refined vegetable oils during storage

Abstract

Edible oils constitute an important component of human diet. They are source of essential fatty acids, having important role in cellular metabolism to store and provide energy when required. Oxidation of oils modifies organoleptic properties thereby affecting the shelf life of the product. Lipid oxidation of oils decreases the nutritional quality along with production of rancid odour, unpleasant flavour and discoloration. Therefore, the assessment of edible oils quality in terms of their oxidative stability is important to determine their shelf life at household conditions in order of their timely consumption. The quality of refined and crude oils was evaluated using several parameters such as: peroxide value, acid value, iodine value, p-anisidine value (p-AV), TBARS value, Totox value, moisture content, β-carotene content, α-tocopherol content and free fatty acid content at 0, 30, 60 and 90 days after storage (DAS). Our results revealed that the oxidative parameters of edible oils increased significantly (P ≤ 0.05) beyond their set limits depicting increase in rancidity with storage.