The Antioxidative and Antibacterial Effect of Origanum Vulgare Essential oil on Surimi Shelf life during Frozen Storage

This study was conducted to evaluate the antioxidant and antimicrobial effects of Oregano (Origanum Vulgare L.) essential oilon surimi preservation during freeze keeping. After manually production of surimi, half of it was mixed with cryoprotectant and used as a control and the other half was mixed with 0.5% of oregano essential oil (w/v), packed in plastics and then stored at -18°C for 0, 1, 3 and 6 month, respectively. The results showed that there was no significant difference between treatments in the case of ash (%) however; protein and fat (%) were significantly lower in control (surimi without additive) than those supplemented with oregano. TBA, TVN and peroxides significantly decreased in oregano treated surimi in all months compared to control. After 0, 1 and 3 month, total psychrophilic (TPC) and pseudomonas bacteria were similar in both treatments. However, total amount of bacteria significantly decreased in treated surimi at the end of 6 month storage as compared to control. The results of color indexes showed that, there was no difference in redness index in all periods; however whiteness and yellowness indexes were significant after 1 and 6 month and lighting index in treated surimi after 1, 3 and 6 month storage. Generally, it can be concluded that, addition of oregano essential oil at 0.5% w/v can improve antimicrobial and antioxidant properties and decrease microbial and oxidative spoilage in surimi.