采用单因素实验和响应面优化实验对草鱼内脏中鱼油的钾法提取工艺进行研究,并对其脂肪酸组成和氧化稳定性进行了分析。实验结果表明:鱼油提取的最佳工艺条件为pH 8.4,水解温度61.28℃,水解时间41.6 min,KCl用量为4.29%,液料比为1∶1,盐析时间为10 min。采用逐步回归拟合,获得鱼油提取率的预测模型如下:提取率/%=-1 374.0+102.780A+11.111B+28.912C+26.190D-7.005 5A2-0.071 5B2-0.302 2C2-10.259D2+3.495 0AD-0.086 2BC+0.289 5BD+0.353 0CD,最佳提取率预测值为55.95%,实测值为55.84%。通过对精炼鱼油的脂肪酸分析,共检出13种脂肪酸,脂肪酸中以棕榈酸、油酸和亚油酸为主。其中不饱和脂肪酸占74.32%,饱和脂肪酸占25.68%,必需脂肪酸占24.14%。ω-3脂肪酸(EPA和DHA)含量占多不饱和脂肪酸含量的2.94%,顺式脂肪酸含量占不饱和脂肪酸含量高达99.98%。氧化稳定性研究表明,鱼油的诱导时间为0.18 h。

The single-factor experiments and response surface methodology experiments were used to optimize KCl extraction processing of oil from grass carp viscera and oil's fatty acid composition and oxidation stability were analyzed. Experimental results showed that optimal processing of oil for grass carp viscera was : pH 8. 4,hydrolysis temperature 61. 28 ℃,hydrolysis time 41. 6 min,KCl content 4. 29%,liquid to solid ratio 1 ∶ 1,salting-out time 10min. By gradual regression fitting,the optimal predictive model was: Extraction rate( %) =- 1374. 0 + 102. 780A +11. 111B + 28. 912C + 26. 190D- 7. 0055A2- 0. 0715B2- 0. 3022C2- 10. 259D2+ 3. 4950AD- 0. 0862BC +0. 2895BD + 0. 3530CD. Use the above model,the predicted value was 55. 95%,and actual value was 55. 84%. By fatty acid analysis of refining fish oil,the results were: 13 kinds of fatty acid were determined,particularly palmitic acid,oleic acid and linoleic acid. The unsaturated fatty acids was at 74. 32% of the total fatty acids,saturated fatty acids was 25. 68%,essential fatty acids was at 24. 14%,ω-3 fatty acids( EPA DHA) was to 2. 94% of polyunsaturated fatty acids,and cis-fatty acids was to 99. 98% of unsaturated fatty acid. This indicated the fish oil had good nutrition value. Oxidation stability studies showed that oxidation induction time of fish oil was 0. 18h. This study provided a theoretical basis of fish oil extraction and storage.