Effect of hydrostatic pressure and holding time on physicochemical quality and microbial inactivation kinetics of black tiger shrimp (Penaeus monodon)

The effects of high pressure processing (HPP), applied within 300-600 MPa for 3-15 min at ambient temperature (27 +/- 2 degrees C) on physicochemical (color, texture, trimethylamine nitrogen and thiobarbituric acid content) attributes and inactivation kinetics of natural microbiota (total aerobic mesophiles, psychrotrophs, Escherichia coli, and Staphylococcus aureus) in black tiger shrimp (Penaeus monodon) were investigated. The color parameters L* (lightness) and b* (yellowness) increased but a* (redness) decreased with pressure and holding time imparting a brighter and mildly cooked appearance to shrimp muscle. Pressure-induced lipid oxidation accelerated at pressure treatments of 400-600 MPa. Hardness was found to be influenced by both pressure level and holding time. Among the group of microorganisms studied, pressure sensitivity of E. coli was found to be maximum whereas aerobic mesophiles were least sensitive (z(p) values of 421 MPa and 714 MPa; Delta V values of -18.60 x 10(-5) and -9.13 x 10(-5) m(3) mol(-1), respectively). Industrial relevance: High pressure processing (HPP) is a promising seafood preservation technique and has been successfully applied over a range of seafood. Shrimp is a high value commodity with constant demand in the seafood market, but it is highly perishable. This study will demonstrate the changes induced by HPP in black tiger shrimp which may further be applied to develop the process technology to preserve the valuable catch. (C) 2015 Published by Elsevier Ltd.