Our aim was to study the effect of phenyllactic acid treatment on the quality of channel catfish during low temperature storage. Channel catfish was treated with phenyllactic acid (0.5, 1.5 or 2.5 g/100 mL) and stored at 4 ℃. The changes of total bacterial count (TBC), total volatile basic nitrogen (TVB-N) content, thiobarbituric acid reactive substances (TBARs) value, water-holding capacity (WHC), texture, color and sensory quality were analyzed. It was found that TBC, TVB-N content and TBARs value of channel catfish treated with phenyllactic acid were significantly lower than those of the control group, indicating that phenyllactic acid preserves the quality of channel catfish; the most pronounced effect was observed at 2.5 g/100 mL, but compared with the other concentration groups, little differences were found in pH, WHC, color and texture. In general, treatment with 2.5 g/100 mL phenyllactic acid can significantly prolong the shelf life of channel catfish during low temperature storage while having little effect on its physicochemical properties and sensory evaluation.

In order to explore the effect of irradiation dose on the quality and flavor of crayfish roe from crayfish processing wastewater, changes in safety indexes such as total bacterial count, coliform group, and heavy metal content were analyzed after ⁶⁰Co-γ ray irradiation at different doses (2, 4, 6, and 8 kGy). Meanwhile, the flavor characteristics were evaluated by the combined use of electronic nose and gas chromatography-mass spectrometry (GC-MS). The results showed that irradiation doses ≥ 4 kGy had better inhibitory effects on the total bacterial count and coliform group, and the heavy metal content in the treated sample met the national standard. The results from the electronic nose showed significant differences in the flavor of crayfish roe treated with four different irradiation doses, and the response values for nitrogen-containing oxides and sulfur-containing compounds increased with irradiation dose. The sample treated with a dose of 6 kGy had the highest amount of volatile flavor compounds (19), the predominant ones being aldehydes, alcohols, and heterocycles. The 4 and 6 kGy irradiation groups were more acceptable in sensory evaluation. In general, 6 kGy irradiation was superior to the other doses in terms of safety and flavor.