不同贮藏温度下鱼油品质的变化

为探究鱼油精制前后,即粗制鱼油与精制鱼油在不同贮藏温度下的稳定性变化,分别将其置于35、25、15、5℃恒温箱中贮藏120 d,定期测定其理化指标(酸价、过氧化值与茴香胺值)、脂肪酸组成及挥发性风味成分的变化。结果表明:温度对鱼油品质的作用效果显著,温度越高,其贮藏稳定性越差,品质变化越大,且精制鱼油的贮藏稳定性较粗制鱼油差;在贮藏期内,鱼油酸价、过氧化值及茴香胺值均明显升高;其饱和脂肪酸总含量升高,不饱和脂肪酸总含量降低,使脂肪酸整体不饱和度下降;1-戊烯-3-醇、壬醛、己醛、2-壬酮、2-十一酮、乙酸及丁酸含量变化较明显,对鱼油整体风味影响极大。本研究结果对提高鱼油贮藏稳定性及延长货架期有理论参考意义。

Quality Changes in Crude and Refined Fish Oil at Different Storage Temperatures

In order to evaluate the stability of crude and refined fish oil at different storage temperatures, fish oil samples were stored in four thermostats at 35, 25, 15 and 5 ℃ for 120 days, respectively and changes in physicochemical indexes (acid value, peroxide value, and anisidine value), fatty acid profile, and volatile compounds were detected at regular intervals during the storage period. The results showed that the effect of storage temperature on the quality of fish oil was significant and the higher the temperature, the worse the stability and the greater the quality changed. Moreover, the stability of refined fish oil was worse than that of crude fish oil. During the storage period, the acid value, peroxide value and anisidine value of fish oil increased significantly; the content of total saturated fatty acid (SFA) increased, and the content of total unsaturated fatty acid (UFA) decreased, thereby decreasing the overall degree of unsaturation. In addition, the volatile flavor compounds 1-penten-3-ol, nonanal, hexanal, 2-nonanone, 2-undecanone, acetic acid, and butyric acid changed significantly, greatly affecting the overall flavor of fish oil. The results from the present study will provide a theoretical basis for improving the storage stability and prolonging the shelf life of fish oil.