烹饪时间对鱼肉中脂肪酸的影响

Effect of cooking time on fatty acids in fish

中文关键词:  脂肪酸  鱼肉  烹调时间  氯仿-甲醇法

英文关键词:fatty acid  fish meat  cooking time  chloroform-methanol method

中文摘要:

      目的 考察不同烹饪时间对鱼肉中脂肪酸营养价值的影响, 并对不同鱼类的适宜烹调时间进行评价。方法 采用清蒸的方式对秋刀鱼、石斑鱼、鲫鱼和罗非鱼进行烹调, 利用氯仿-甲醇提取法提取鱼肉脂肪酸, 通过气相色谱技术(gas chromatography, GC)对鱼肉中脂肪酸进行定性定量, 讨论烹饪时间对不同鱼肉中脂肪酸含量变化的影响。结果 随着烹饪时间的增加, 4种不同种类的鱼肉中不饱和脂肪酸的含量都呈现下降趋势, 当烹饪时间为0.5~1.0 h时, 不饱和脂肪酸二十碳五烯酸(eicosapentaenoic acid, EPA)、二十二碳六烯酸(docosahexaenoic acid, DHA)、油酸、亚油酸、亚麻酸含量下降速率最快并且产生有害脂肪酸(反式脂肪酸), ω-6/ω-3脂肪酸比值也呈现出上升趋势, 鱼肉脂肪酸营养价值降低。结论 在对鱼肉进行烹饪时, 应严格控制鱼肉烹饪时间在0.5 h左右, 才能有效的保证鱼肉中脂肪酸的营养价值。

英文摘要:

      Objective To investigate the effects of different cooking time on the nutritional value of fatty acids in fish, and evaluate the suitable cooking time of different fish. Methods Cololabis saira, Epinephelussp, Carassius auratus, Tilapia nilotica were firstly steamed, and the fatty acid of fish was extracted by chloroform-methanol extraction. The qualitative and quantitative analysis of fatty acids in fish was analyzed by gas chromatography (GC), and the effect of cooking time on the change of fatty acid content in fish meat was discussed. Results The content of unsaturated fatty acids in 4 different types of fish showed a downward trend over cooking time. When the cooking time was 0.5~1.0 h, the unsaturated fatty acid (eicosapentaenoic acid, docosahexaenoic acid) content decreased at the fastest rate and produced harmful fatty acids (trans fatty acids). The ratio of omega-6/ω-3 fatty acids also showed an upward trend, and the nutritional value of fish fatty acids decreased. Conclusion The cooking time of the fish should be strictly controlled at about 0.5 h, which can effectively guarantee the nutritional value of the fatty acids in the fish.