Stability of chloramphenicol residues in shrimp subjected to heat processing treatments.

The stability of chloramphenicol residues in white shrimp (Penaeus indicus) subjected to cooking (100 degrees C) for 10, 20 and 30 min (C1, C2 and C3) as well as retorting (121 degrees C) for 10 and 15 min (R1 and R2) was studied by a microbial assay method using Photobacterium leiognathi as the test organism. The microbial assay method was found to have a good sensitivity of 1 microg/ml the loss of chloramphenicol in shrimp subjected to cooking for 10, 20 and 30 min was 6%, 12% and 29%, respectively. Similarly, the loss was 9% and 16% from the shrimp subjected to retorting for 10 and 15 min, respectively. The loss of chloramphenicol was found to increase with increase in temperature and duration of heating. This study showed that chloramphenicol is an unstable aquaculture drug that is destroyed or degrades during heat processing treatments.