Comparison between the effects of α-tocopherol and BHT on the lipid oxidation of Kilka fish

Three species of kilka (Clupeonella spp.) in the Caspian Sea have a high commercial value. In Iran it is use to produce canned, marinated packs and paste in making sausage and nugget. Kilka is a nutritious fish with high level of iron and considerable level of polyunsaturated fatty acids making it prone to auto-oxidation. The quality of kilka is the most important factor affects on its products, therefore antioxidants can be used during kilka handling and storage. Since consumers tend to choose products with natural additives, in this study the effects of α -tocopherol on the kilka fish oxidation is compared with BHT. Kilka was immerged in 0.1, 0.5 and 1 perecent w/v basis concentrations of α -tocopherol and BHT for 15 minutes, and then treated samples were packed separately and stored at 4oC. The inhibitory effects of α -tocopherol on the outooxidation of kilka was investigated every 24 hours over a period of 4 days by monitoring changes in peroxide value, free fatty acid content as well as thiobarbituric acid reactive substances. Results showed that there was no significant difference ( p>0.05) between 1% levele of α tocopherol and the same level of BHT. One percent of α -tocopherol is therefore regarded as the preferred concentration for controlling oxidation of kilka oil on the basis of efficacy.