Effect of chitosan coating combined with green tea extract on the melanosis and quality of Pacific white shrimp during storage in ice

Abstract

The subject of present study was to evaluate the effect of chitosan coating combined with green tea extract (GTE) on the melanosis formation and quality of Pacific white shrimp (Litopenaeus vannamei) during 9 days of storage in ice. The melanosis formation was significantly inhibited and sensory quality was significantly improved in shrimp treated with chitosan coating, GTE and chitosan coating combined with GTE, compared with the control. The increase in the total bacteria amounts, pH and total volatile basic nitrogen were significantly inhibited in shrimp treated with chitosan coating, GTE and chitosan coating combined with GTE. The melanosis score and total volatile basic nitrogen of shrimp treated by chitosan coating combined with GTE was less than that treated by chitosan coating or GTE alone. These results suggested that chitosan coating combined with GTE could be used as an effective natural alternative to synthetic antimelanosic agents to inhibit post-mortem melanosis and improve the quality of shrimp during storage in ice.