Formation of biogenic amines and quality of shrimp (Feneropenaeus indicus) treated with combinations of chitosan, NaCl and citric acid under refrigerated storage

Abstract

Shelf life of post-harvest shrimp varies depending on processing and storage conditions. As seafood is highly susceptible to contamination by microorganisms producing biogenic amines, monitoring of biogenic amine levels under various treatment conditions is essentially important. The effect of 1 per cent chitosan in combination with 1.5 per cent NaCl and 1.5 per cent citric acid on the biochemical and microbial quality characteristics and formation of biogenic amines of Indian white prawn under refrigerated storage was carried out. The biogenic amines which showed specific change during storage were putrescine and cadaverine. The putrscine and cadaverine content of chitosan – NaCl treated sample was significantly lower than that of control on the day of rejection (9th day). The chitosan-NaCl treated sample got rejected on 9th day of storage with a putrescine and cadaverine content of 4.96 and 1.2 ppb respectively. While the chitosan-citric acid treated sample got rejected on 7th day of storage with a putrescine and cadaverine content of 19.35 and 0.34 ppb respectively. A lower increase of pH and TVBN was observed in both the treatments compared to control sample which got rejected sensory wise on 5th day of storage. Loss of freshness and melanosis of treated samples was lower than that of control. The mesophilic count of T1 and T2 reached 7 log cfu/g on 9th and 7th day respectively.