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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
The effect of rosemary extract and oregano extract was compared with Butylated Hydroxytoluene (BHT) which was incorporated in chitosan film and studied the quality and shelflife of Indian Mackerel (Rastrelliger kanagurta) steaks during ice storage. The quality of the product was analysed by using biochemical methods (peroxide value, free fatty acid, thiobarbituric acid, trimethyl amino nitrogen, total volatile basic nitrogen, pH), microbial methods (total plate count) and sensory quality. The antioxidant properties of rosemary and oregano extracts were tested in vitro at varied concentrations (100 to 500 ppm) and growth inhibition was seen against gram positive and gram negative bacteria by disc diffusion method. It was observed that 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of Rosemary and Oregano extracts at 100ppm concentration were 77.37% and 62.86% respectively. Rosemary extract showed highest ferric reducing activity at all concentrations(100-500ppm) and exhibited highest reducing power at 500 µg /mL, almost equivalent to BHT at 200 mg/L. Rosemary extract exhibited more chelating activity compared to oregano extract, although both extracts were less efficient compared to synthetic metal chelator, Ethylene diamine tetraacetic acid (EDTA). Rosemary and Oregano extracts were potentially active against gram+ve bacteria whereas, it showed smaller zones of inhibition against gram-ve bacteria. The effect of 1% chitosan, 1% chitosan with 200ppm of BHT, 1% chitosan with 500ppm of rosemary and 1% chitosan with 500 ppm of oregano treatments on quality changes of Indian mackerel steaks during ice storage for 21 days were investigated.