Novel functional salad dressings were formulated by replacing corn oil in conventional salad dressing by red palm olein (RPOL) at 5%, 10%, 15%, 20%, 40%, 60% and 80% levels. Sensory evaluation revealed that salad dressing made from 15% RPOL and 85% corn oil was quite acceptable as the conventional salad dressing (100% corn oil). Therefore, the former two formulas were selected for subsequent evaluation. Salad dressings were stored at room temperature (24°C±2) for 6 months and monitored for their physical properties, fat stability, fatty acid composition and natural antioxidants, namely carotenes, tocopherols and tocotrienols.
The data revealed that the replacement of corn oil in functional salad dressing led to a significant increment in α, γ and δ tocotrienols (29 folds) and carotenes (15 folds) as compared to the control. Storage of salad dressing made from 15% RPOL for 6 months led to significant declines in peroxide and p-anisidine values and little declines in saturated and polyunsaturated fatty acids, as compared to the control. Utilization of RPOL as a replacer of corn oil revealed positively significant effects on stability of salad dressing along with maintaining high content of natural antioxidants.