EFFECT OF HEATING TIME AND HEAT ON THE PHYSICOCHEMICAL AND ANTIOXIDATIVE PROPERTY OF FISH (LABEO ROHITA) SKIN OIL

Abstract

Objective: Determination of oxidative and thermal stability of Labeo rohita skin oil.
 Methods: Labeo rohita skin oil was extracted by soxhlet method using n-hexane as solvent. Acid value, Free Fatty Acid content, the Peroxide value of the oil was determined and the same was also determined after heating the oil at 90 °c for 1 hour to check whether the oil is thermally stable or not. Antioxidant activity was determined via Total Phenolic content (TPC), 2, 2-Diphenyl-1-picryl hydrazyl (DPPH) free radical scavenging activity and Ferric Reducing Antioxidant Power (FRAP) assay. Oxidative stability was determined by heating the oil at a constant temperature of 90 °c for 1 hour, 2 hour, 3 hour, and 4 hour. The oil was also heated at 60 °c, 120 °c, and 18 °c for a constant time of 2 h.
 Results: Heating increases the scavenging activity of Labeo rohita skin oil as measured by the 2, 2-Diphenyl-1-picryl hydrazyl (DPPH) method. Total phenolic content (TPC) value and Ferric reducing antioxidant power (FRAP) assay value is decreased both with an increase in heating time (**p<0.05) and heating temperature (p<0.01). Acid value and FFA (Free Fatty Acid) content and Peroxide value is increased with an increase in temperature (**p<0.01)
 Conclusion: The Present study explores that Labeo rohita skin oil both thermally and oxidatively stable The results indicate that the oil can be used in food formulation as well as a new cooking oil substitute.