Meidell Line Skontorp, Slizyte Rasa, Mozuraityte Revilija, Carvajal Ana Karina, Rustad Turid, Falch Eva
Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7012 Trondheim, Norway.
Department of Fisheries and New Biomarine Industry, SINTEF Ocean, 7010 Trondheim, Norway.
Foods. 2024 Jul 4;13(13):2133. doi: 10.3390/foods13132133.
Silaging can be used as preservation technology to valorize currently discarded raw material into protein hydrolysate on board deep-sea vessels. The aim of this study was to investigate the effect of sorting and raw material freshness on the quality and yield of protein hydrolysates obtained through silaging of saithe () viscera. Additionally, the effect of using acid-containing antioxidants was tested. Out sorting of the liver prior to silaging resulted in slightly higher hydrolysate yields. The hydrolysates with the highest protein contents were obtained from silages made from fresh raw materials (day 0), and the content decreased significantly after longer storage of the raw material (2-3 days at 4 °C). Storage of the raw material for 1 day did not affect the quality. However, a significantly higher degree of hydrolysis (DH), content of free amino acids (FAA), and total volatile basic nitrogen (TVB-N) were obtained when raw materials were stored for 3 days. The FAA composition was influenced by the raw material's freshness, with increases in free glutamic acid and lysine and a decrease in free glutamine after longer storage. None of the studied parameters were significantly affected by out sorting of liver or the addition of antioxidants. Overall, the results indicate that the whole fraction of the viscera can be utilized without reducing the quality of the hydrolysate and that the raw material should be stored for a maximum of 1 day prior to preservation to optimize the quality.
青贮可作为一种保存技术，将目前被丢弃的原材料在深海船只上转化为蛋白质水解物。本研究的目的是调查分拣和原材料新鲜度对通过腌制绿鳕（）内脏获得的蛋白质水解物的质量和产量的影响。此外，还测试了使用含酸抗氧化剂的效果。在青贮前将肝脏分拣出来，水解物产量略高。蛋白质含量最高的水解物来自用新鲜原材料（第0天）制成的青贮饲料，在原材料长时间储存（4℃下2 - 3天）后，含量显著下降。原材料储存1天不影响质量。然而，当原材料储存3天时，水解度（DH）、游离氨基酸（FAA）含量和总挥发性盐基氮（TVB - N）显著更高。FAA组成受原材料新鲜度影响，长时间储存后游离谷氨酸和赖氨酸增加，游离谷氨酰胺减少。所研究的参数均未因肝脏分拣或添加抗氧化剂而受到显著影响。总体而言，结果表明内脏的整个部分都可以利用而不降低水解物的质量，并且原材料在保存前应最多储存1天以优化质量。
