目的 制备壳聚糖纳米硒(CS-SeNPs)，将其应用于南湾鱼肉的冷藏保鲜，以延长货架期。方法 以壳聚糖作为稳定剂和分散剂，通过化学还原法，在抗坏血酸的作用下还原亚硒酸钠，制备CS-SeNPs;以壳聚糖浓度、亚硒酸钠和抗坏血酸摩尔比(Vc/Na2SeO3)、反应温度及反应时间为因素进行单因素试验，在试验基础上，以CS-SeNPs的稳定性为响应值，选择壳聚糖浓度、Vc/Na2SeO3、反应温度作为考察对象，通过响应面优化试验得到CS-SeNPs的最佳制备工艺;将CS-SeNPs应用于南湾鱼肉的保鲜，考察其贮藏保鲜效果。结果 CS-SeNPs的最佳工艺参数如下:壳聚糖浓度为20 g/L，反应温度为40 ℃，Vc/Na2SeO3摩尔比为4∶1，此时A410/A490为2.176±0.008 6。与对照组相比，经CS-SeNPs处理后具有更好的保鲜效果，能延缓鱼肉贮藏期间脂质氧化、菌落总数、总挥发性盐基氮值与汁液流失率的升高，保持鱼肉的pH值，延长其冷藏货架期。相关性分析表明，TVB-N值和汁液流失率与冷藏鱼肉贮藏品质相关性极强。结论 与对照组相比，保鲜组能将南湾鱼肉的冷藏货架期延长3~6 d，为CS-SeNPs在保鲜方面的应用提供一定的数据支撑。

The work aims to prepareChitosan nano-selenium (CS-SeNPs) and apply it in the cold storage of South Bay fish to prolong its shelf life. CS-SeNPs was prepared by chemical reduction of sodium selenite with ascorbic acid using chitosan as stabilizer and dispersant. A single factor test was conducted with the concentration of chitosan, the molar ratio of sodium selenite to ascorbate (Vc/Na2SeO3), reaction temperature and reaction time as factors. On the basis of the test, the stability of CS-SeNPs was taken as the response value, and the concentration of chitosan, Vc/Na2SeO3 and reaction temperature were selected as the objects of investigation. The optimum preparation process of CS-SeNPs was obtained by response surface optimization test. CS-SeNPs was applied to the preservation of South Bay fish and its preservation effect was investigated. The optimum process parameters of CS-SeNPs were as follows:the concentration of chitosan was 20 g/L, the reaction temperature was 40 ℃, the molar ratio of Vc/Na2SeO3 was 4:1, and the A410/A490 was 2.176±0.008 6. Compared with the control group, CS-SeNPs after treatment had a better fresh-keeping effect, which could delay the increase of lipid oxidation, the total number of colonies, the total volatile base nitrogen value and the SAP loss rate during fish storage, maintain the pH value of fish and extend the shelf life of fish in cold storage. The correlation analysis showed that the value of TVB-N and the rate of juice loss were highly correlated with the storage quality of frozen fish. Compared with the control group, the refrigerated shelf life of South Bay fish can be extended by 3-6 days in the treatment group, which provides certain data support for the application of CS-SeNPs in preservation.