电子束辐照处理对鮰鱼冷藏期间品质的影响

以新鲜鮰鱼为原料，利用电子束辐照（0、1、3、5 kGy）结合真空包装于4 ℃条件下冷藏，通过测定菌落总数、总挥发性盐基氮（total volatile basic nitrogen，TVB-N）含量、硫代巴比妥酸反应物（thiobarbituric acid reactive substance，TBARs）值、质构、色度、持水性、感官品质和挥发性物质的变化，研究不同辐照剂量对鮰鱼冷藏期间品质的影响。结果表明：经过电子束辐照处理的鮰鱼贮藏期显著延长，未辐照冷藏时间为6 d，1、3、5 kGy辐照组分别为15、25、30 d；在冷藏期间，辐照组菌落总数在冷藏15 d达到6 （lg（CFU/g）），TVB-N含量在冷藏25 d时达到20 mg/100 g，辐照组菌落总数与TVB-N含量的增长速率显著低于未辐照组，且随辐照剂量的增大，增长速率下降，未辐照组的TBARs值明显低于辐照组，辐照加速了脂肪氧化速率，辐照处理对鮰鱼的持水性、质构和色度影响不大。

Effect of Electron Beam Irradiation on Quality of Channel Catfish during Cold Storage

In this study, small pieces of fresh channel catfish flesh treated by electron beam irradiation at different doses (0, 1, 3 and 5 kGy) combined with vacuum packaging were stored at 4 ℃ and evaluated for total viable count (TVC), total volatile base nitrogen (TVB-N) content, thiobarbituric acid reactive substances (TBARs) value, texture, color, water-holding capacity, sensory quality and volatile substances. The results showed that the storage period of electron beam irradiated channel catfish was significantly prolonged compared with the untreated control group (15, 25 and 30 days at doses of 1, 3 and 5 kGy versus 6 days, respectively). On day 15 of storage, the TVC in the irradiated group reached 6 (lg (CFU/g)), and the TVB-N content reached 20 mg/100 g on day 25. The growth rate of TVC and TVB-N content in the irradiated group was significantly lower than in the non-irradiated group, and declined with increasing radiation dose. Moreover, the TBARs value of the non-irradiated group was significantly lower than that of the irradiated group, indicating that the irradiation could accelerate the rate of lipid oxidation. On the other hand, the irradiation treatment had little effect on the water-holding capacity, texture or color of channel catfish.