EFFECT OF BLENDING ON SENSORY ODOR PROFILE AND PHYSICO-CHEMICAL PROPERTIES OF SELECT VEGETABLE OILS

Edible oils of common use in households are mainly of vegetable origin. The present trend of globalization and emphasis on nutritional enrichment has led to the exploration of usage of blended oils. Binary blends studied in this work consisted of 80% base oil (mustard, groundnut and sunflower oil) and 20% blending oil (sesame, refined palm and rice bran oil). The sensory odor profiling of base oils, namely sesame blending oils and their blends was monitored by Sniff test method. The characteristic notes of mustard oil were more of sulfury, pungent and sour while that of palm oil was more husk-like; sesame oil, seedy and earthy notes; rice bran oil was branny, earthy and groundnut oil more nutty, and had a fresh oil-like note on the profilogram. Profilogram of blends showed a decrease in the intensities of dominating notes of the base oils. The color measurement of blended oils showed variation in L*, a*and b*values with a⁺(redness) for refined palm oil blends, b⁺(yellowness) for sesame and mustard oil blends and a^-(greenness) for rice bran oil blends. The sensory color perception values and CIE color values for L*, a*and b*were negatively correlated for lightness (L*) and sensory redness color values (r=-0.67; p<0.05), while a positive correlation existed between a*and sensory redness values (r=0.72; p<0.05). The apparent viscosity of the oil blends indicated a pseudoplastic shear thinning behavior. The apparent viscosity of the base oils increased when blended with sesame or rice bran oil, while it decreased upon blending with refined palm oil.