EFFECTS OF HEATING TEMPERATURE AND β-CAROTENE ON QUALITY AND FATTY ACIDS COMPOSITION OF VEGETABLE OILS

The purpose of the study was to investigate the effects of temperature and )3-carotene addition on the quality parameters of corn and palm oils subjected to heating. Vegetable oils and 0.005% )3-caroten additivated oils were heated at varying temperatures (100, 130, 160, 190 and 220 degrees C for 30 minutes) to follow quality alterations. Peroxide value, total polar compounds, refractive index value, iodine value and fatty acids composition were determined to measure the degree of oxidative rancidity. Peroxide value was significantly (p < 0.001) influenced by the type of oil, additivation and heating temperature. Palm oil with added antioxidant showed the smallest increase in polar compounds during the heat treatment. Corn oil fatty acids profile was rich in oleic (C18:1), arachidonic (C20:4), eicosenoic (C20:1), and linoleic (C18:2) fatty acids, followed by alphalinolenic (C18:3) and palmitoleic (C16:1) acids. Polyunsaturated fatty acids and monounsaturated fatty acids content decreased during heat treatment. Statistical analysis of the data revealed that the development of rancidity in vegetable oils subjected to heating was significantly (p < 0.01) reduced by the addition of )3-carotene in concentration of 0.005%.