Comparative effects of chlortetracycline, freezing, and gamma radiation on microbial population of ocean perch.

The microbial populations in chlortetracycline (CTC)-treated (50, 100, 200, and 500 ppm), frozen (-15 C), and irradiated (0.1 Mrad) ocean perch (Sebastodes alutus) were compared. The control sample spoiled at 7 C, primarily because of the growth of Pseudomonas. Irradiation changed this to Achromobacter-dominated spoilage. Freezing or CTC treatment altered the spoilage pattern very little. CTC was particularly effective against ultraviolet fluorescent Pseudomonas species at the higher concentrations. Freezing and CTC were not effective against "coryneforms."