Effect of α-tocopherol on the storage stability of rista

Abstract

The effect of incorporation of a-tocopherol (0.02%) on the quality and storage stability of Rista was studied. The pH and stability of raw emulsion of Rista formulated with a-tocopherol (T1) was significantly (P<0.05) lower than control emulsion (T0). In the cooked products, pH, cooking yield and proximate composition except ash content of Rista showed significant (P<0.05) differences. The overall palatability scores of Rista samples showed comparable results between the two groups. Another objective was to assess the effect of a-Tocopherol as antioxidant on the storage stability of Rista in refrigerated storage for 3 weeks at 4±1°C. The pH and moisture of Rista samples increased significantly (P<0.05) during storage. Thiobarbituric acid value of Rista samples increased significantly (P<0.05) with the advancement of storage. However, the values even at the end of storage period were well within the reported safe limits and not indicative of any rancidity. The total plate and coliform counts of Rista samples increased significantly (P<0.05) during storage. Yeasts and moulds were detected only from day 14 of storage and then increased significantly (P<0.05) by the end of day 21 of storage. Microbial counts in general remained low and well within permissible limits even at the end of the storage period. The results of sensory evaluation revealed a gradual decrease in the scores of various attributes with the advancement of storage. However, the scores even at the end of storage period remained generally in the range of above six indicating good acceptability of the product. It was concluded that the incorporation of α-tocopherol at 0.02% level, in Rista could be one of the alternatives to address the problem of lipid oxidation with beneficial effects on quality and storage stability.