Fatemeh Khedri; Ainaz Khodanazary
Abstract
Introduction: The mackerel (Scomberomorus commerson; Scombridae) also known as "Sheer fish" in Persian, is the most popular fish in Iran with the highest economic value. This fish is mainly offered on the Iranian market as skinned and boneless fillets. Major changes occur in proximate, microbiological, ...
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Introduction: The mackerel (Scomberomorus commerson; Scombridae) also known as "Sheer fish" in Persian, is the most popular fish in Iran with the highest economic value. This fish is mainly offered on the Iranian market as skinned and boneless fillets. Major changes occur in proximate, microbiological, chemical and sensory composition of fish fillets during storage in the refrigerator. To preserve the fish fillet, antioxidant additives prior to packaging is a common practice used in food market to extend the shelf life of aquatic products. Currently, synthetic antioxidants such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) frequently have been used prior to packaging. However, recently the consumers’ demand has ben changed to fillets with natural preservatives such as green tea extract (GTE), usually packaged in vacuum packaging (VP). Green tea is a good source of polyphenolic compounds such as catechina having strong antioxidant and antimicrobial properties. Incorporating GTE as a food additive due to its antioxidant activities is a growing interest in the seafood industry. GTE can improve the marketing potential of various seafood products and can effectively be used in the packaging food industry.Materials and method: Mackerel, Scomberomorus commerson was purchased from a local fish market in Abadan city, Khozestan province, Iran. Fish were freshly caught and completely free of additives. The fish samples were kept in ice with a fish/ ice ratio of 1:2 (w/w) and transported to the seafood processing laboratory within one hour. Upon arrival, fish samples were washed in cold water and each sample was carefully filleted by hand. Two fillets were obtained from each fish after removing the head and bone. Mackerel fillet were soaked with 1 g GTE/ L solution at a fillet/solution ratio of 1: 2 (w/v) for 15 min at 4 °C, followed by draining on the screen for 3 min at 4 °C. The trays of containing samples were then vacuum- packaged (VP).Results and discussion:The results indicated that the bacterial experiments (total count and pscychrotrophic bacteria) showed the antibacterial effect of green tea extract. Lipid oxidation value experiments (peroxide and thiobarbituric values) showed lower oxidation value in fillets treated with GTE, compared to fish kept under vacuum packaging without treatment and the control (P
