Felisiak Katarzyna, Szymczak Mariusz
Department of Fish, Plant and Gastronomy Technology, Faculty of Food Sciences and Fisheries, West Pomeranian University of Technology, 71-459 Szczecin, Poland.
Department of Toxicology, Dairy Technology and Food Storage, Faculty of Food Sciences and Fisheries, West Pomeranian University of Technology, 71-459 Szczecin, Poland.
Foods. 2021 Oct 20;10(11):2518. doi: 10.3390/foods10112518.
Currently, herring fillets are salted with acetic acid to activate muscle proteases. This causes a change in the composition of free amino acids, compared to salting of whole fish with viscera proteases. Therefore, old indicators of the ripening dynamics of salted fish based on amino acids are not current. Determination of free amino acids can be performed by many methods, but most are labor intensive and expensive. Therefore, a capillary electrophoresis method without derivatization (CZE) was used to determine the actual ripening rates of salted herring fillets. A group of hydrophobic and basic amino acids were determined in trichloroacetic acid (TCA) extracts of meat and brine to develop 16 indicators. Statistical regression analysis of the indicators (R2adj, RMSE, cluster analysis) followed by principal component analysis (PCA) correlation analysis of the indicators vs sensory evaluation parameters of texture and TPA-hardness of salted fillet meat allowed the choice of the most precise indicators. The best indicator in meat was Phe/Tyr-height, which value increased during salting. A more precise indicator of ripening was His/Tyr-height in brine, which value decreased during salting. Sensory evaluation parameters of salted herring texture correlated strongly with TPA-hardness and traditional indicators such as non-protein nitrogen and protein hydrolysis product fraction content. However, the most precise indicators were those obtained from amino acids determined by the CZE method. Results obtained in this study may be suitable for fast monitoring of the salted herring ripening process in industry.
目前，鲱鱼片用醋酸腌制以激活肌肉蛋白酶。与用内脏蛋白酶腌制整条鱼相比，这会导致游离氨基酸组成发生变化。因此，基于氨基酸的咸鱼成熟动力学的旧指标已不再适用。游离氨基酸的测定可以通过多种方法进行，但大多数方法劳动强度大且成本高。因此，采用了一种无衍生化的毛细管电泳法（CZE）来测定腌制鲱鱼片的实际成熟率。在肉和盐水的三氯乙酸（TCA）提取物中测定了一组疏水和碱性氨基酸，以建立16个指标。对这些指标进行统计回归分析（调整后的R2、均方根误差、聚类分析），然后对指标与腌制鱼片肉的质地和TPA硬度的感官评价参数进行主成分分析（PCA）相关性分析，从而选择出最精确的指标。肉中最佳指标是苯丙氨酸/酪氨酸高度，其值在腌制过程中增加。盐水中成熟的更精确指标是组氨酸/酪氨酸高度，其值在腌制过程中下降。腌制鲱鱼质地的感官评价参数与TPA硬度以及非蛋白氮和蛋白质水解产物分数含量等传统指标密切相关。然而，最精确的指标是通过CZE法测定的氨基酸所获得的指标。本研究获得的结果可能适用于工业中腌制鲱鱼成熟过程的快速监测。
