بررسي تاثير نايسين Z واستات سديم بر زمان ماندگاري فيله ي كپور نقره اي ( Hypophthalmichthys molitrix ) در طي نگه داري در دماي 4 درجه ي سانتيگراد

Effect of Bacteriocine ¬Z and Sodium Acetate on Shelf-life of Silver Carp (Hypophthalmichthys molitrix) Fillet During Refrigerator Storage

High spoilage of fish has caused preservation of fresh fish quality to be one of the notable important issues in fishery industry and for consumers. In this study the effects of Nisin Z (%0.02) and sodium acetate (2g/100ml) were reviewed separately and simultaneously on silver carp (Hypophthalmichthys molitrix) filet. samples were studied in vacuum for around 9 days at 40c in packed and fillet form and then microbial parameters (the total viable, psycrotrophic and lactic bacteria counts) and chemical parameters (PV, TBA, TVB-N) and so pH value (all over days), total protein, moisture and ash (in first time) were analyzed during 0, 3, 6 and 9 days.TVN and TBA levels in samples containing Nisin and those combined with sodium acetate maintenance increased during the storage period but did not exceed the set limit until day 9, but the control samples had maintained to be unacceptable for consumption to day 4. Review of microbial factors showed that the amount of Psycrophil bacteria, lactic and total bacteria in control samples were higher than the samples containing Nisin and that was also higher than sample containing combined Nisin and sodium acetate, where the amount of total bacteria in control samples, containing Nisin and containing combined sodium acetate and Nisin was set higher than the threshold in the days 4, 6 and 9. Results from chemical and microbial analysis showed that simultaneous use of sodium acetate and Nisin Z could increases the lasting life of silver carp fillet packed in vacuum at temperatures of 40c for 5 days.