Mekonnen Mengistu F, Desta Derese T, Alemayehu Fikadu R, Kelikay Gezahegn N, Daba Alemneh K
School of Nutrition, Food Science and Technology College of Agriculture Hawassa University Hawassa Ethiopia.
College of Medicine and Health Science Hawassa University Hawassa Ethiopia.
Food Sci Nutr. 2020 Aug 2;8(9):4814-4821. doi: 10.1002/fsn3.1760. eCollection 2020 Sep.
During frying, fat degrade and many reactions occur resulting in numerous altered fatty acid products. This would lead to the formation of fatty acids and changes in nutritional qualities. Hence, this study was aimed to determine the changes during frying on fatty acid composition of Nile tilapia () fish muscle from local fish market of Hawassa, Ethiopia. Fish fryers reported that they usually use palm oil for frying. They also indicated that the oil is kept for days and reused for frying at different cycle. In fried fish, 35 types of fatty acids were identified and 27 in raw fish muscle. Palmitic, stearic, heptadecanoic, and tetradecenoic acids were the abundant saturated fatty acids in both fried and raw fish muscle. Oleic, Docosahexaenoic, Eicosapentaenoic, and Linoleic acid were the major unsaturated fatty acids. The percentages of total saturated fatty acids (SFA) of raw fish muscle (47.4%) were found to be lower compared with fried fish muscle (51.8%). The -6-3 ratio (7.83), index of atherogenicity (0.85), and thrombogenicity (1.71) in the fried fish muscle were in the undesirable values. The hypocholesterolemic/hypercholesterolemic ratio was relatively similar in the fried (1.09) and raw (1.02) fish muscles. The total unsaturated fatty acids (UFA) level of raw fish muscle (52.2%) was higher than the fried fish muscle (47.2%). Higher percentage of fatty acid was identified in the fried fish muscle compared with raw. Frying considerably altered fatty acid composition of fish muscle. It increased saturated fatty acid concentration and decreased unsaturated. Hence, frying noticeably decreases the nutritional quality of fish muscle. Therefore, it is suggested that further analysis on fatty acid composition of oil usually used for frying and the nutritional quality index across frying cycles.
在油炸过程中，油脂会降解并发生许多反应，从而产生大量变化了的脂肪酸产物。这会导致脂肪酸的形成以及营养品质的改变。因此，本研究旨在确定埃塞俄比亚哈瓦萨当地鱼市尼罗罗非鱼（）鱼肉在油炸过程中脂肪酸组成的变化。油炸摊主报告称，他们通常使用棕榈油进行油炸。他们还表示，油会保存数天，并在不同周期重复用于油炸。在炸鱼中，鉴定出35种脂肪酸，而生鱼肉中为27种。棕榈酸、硬脂酸、十七烷酸和十四碳烯酸是炸鱼和生鱼肉中含量丰富的饱和脂肪酸。油酸、二十二碳六烯酸、二十碳五烯酸和亚油酸是主要的不饱和脂肪酸。发现生鱼肉中总饱和脂肪酸（SFA）的百分比（47.4%）低于炸鱼肉（51.8%）。炸鱼肉中的-6-3比值（7.83）、致动脉粥样硬化指数（0.85）和血栓形成指数（1.71）处于不理想的值。炸鱼（1.09）和生鱼（1.02）肌肉中的降胆固醇/升胆固醇比值相对相似。生鱼肉中总不饱和脂肪酸（UFA）水平（52.2%）高于炸鱼肉（47.2%）。与生鱼肉相比，炸鱼肉中鉴定出更高百分比的脂肪酸。油炸显著改变了鱼肉的脂肪酸组成。它增加了饱和脂肪酸浓度，降低了不饱和脂肪酸浓度。因此，油炸明显降低了鱼肉的营养品质。因此，建议对通常用于油炸的油中脂肪酸组成以及整个油炸周期的营养品质指数进行进一步分析。
