TEXTURAL CHANGES OF RAW AND COOKED MUSCLE OF SHRIMP, <i>LITOPENAEUS VANNAMEI</i>, INFECTED WITH NECROTIZING HEPATOPANCREATITIS BACTERIUM (NHPB)

Abstract

ABSTRACT Alive white shrimp ( Litopenaeus vannamei ) were experimentally infected with necrotizing hepatopancreatitis bacteria (NHPB) to evaluate the effect of the infection on the postmortem texture of shrimp muscle. The infection percentage was monitored for 18 days. NHPB was propagated in 16.7, 66.7 and 86.4% of shrimp after 7th, 15th and 18th days from experimental infection. Texture profile analysis (hardness, fracturability, elasticity and cohesiveness), shear force and water‐holding capacity (WHC) were monitored in both raw and cooked shrimp muscle sampled from the live stock. No significant differences were detected among infected and healthy shrimp (raw and cooked) during the first 15 days; however, lower hardness, fracturability, elasticity, cohesiveness and WHC were detected in muscle from infected shrimp (cooked and raw) compared with that from healthy shrimp after 18 days. Results suggest that NHPB have a negative impact on the postmortem textural properties of the white shrimp, but the effect is observed only after certain period. PRACTICAL APPLICATIONS Several shrimp farms in Latin American countries are having necrotizing hepatopancreatitis disease problems. As postmortem texture in shrimp muscle is one of the main characteristics for their acceptance in the market and decides its quality, this article attempts to show how the disease affects the postmortem textural properties of the white shrimp muscle.