Valcarcel Jesus, Hermida-Merino Carolina, Piñeiro Manuel M, Hermida-Merino Daniel, Vázquez José Antonio
Group of Recycling and Valorization of Waste Materials, Marine Research Institute (IIM-CSIC), Eduardo Cabello 6, 36208 Vigo, Spain.
Centro de Investigaciones Biomédicas (CINBIO), Departamento de Física Aplicada, Facultad de Ciencias, Universidade de Vigo, 36310 Vigo, Spain.
Int J Mol Sci. 2021 Nov 9;22(22):12104. doi: 10.3390/ijms222212104.
The expansion of fish filleting, driven by the increasing demand for convenience food, concomitantly generates a rising amount of skinning by-products. Current trends point to a growing share of aquaculture in fish production, so we have chosen three established aquaculture species to study the properties of gelatin extracted from their skin: rainbow trout, commonly filleted; and seabass and seabream, marketed whole until very recently. In the first case, trout skin yields only 1.6% gelatin accompanied by the lowest gel strength (96 g bloom), while yield for the other two species exceeds 6%, and gel strength reaches 181 and 229 g bloom for seabass and seabream, respectively. These results are in line with the proportion of total imino acids analyzed in the gelatin samples. Molecular weight profiling shows similarities among gelatins, but seabass and seabream gelatins appear more structured, with higher proportion of β-chains and high molecular weight aggregates, which may influence the rheological properties observed. These results present skin by-products of seabream, and to a minor extent seabass, as suitable raw materials to produce gelatin through valorization processes.
受方便食品需求增长的推动，鱼片加工的扩张相应地产生了越来越多的去皮副产物。当前趋势表明水产养殖在鱼类生产中的占比不断增加，因此我们选择了三种成熟的水产养殖品种来研究从其皮肤中提取的明胶的特性：常见的鱼片加工对象虹鳟鱼；以及直到最近还一直以整条鱼销售的海鲈和海鲷。在第一种情况下，鳟鱼皮的明胶产量仅为1.6%，凝胶强度最低（96克勃氏硬度），而其他两种鱼的产量超过6%，海鲈和海鲷的凝胶强度分别达到181克勃氏硬度和229克勃氏硬度。这些结果与明胶样品中分析的总亚氨基酸比例一致。分子量分析表明明胶之间存在相似性，但海鲈和海鲷的明胶结构似乎更紧密，β链和高分子量聚集体的比例更高，这可能会影响所观察到的流变学特性。这些结果表明，海鲷的皮副产物以及少量的海鲈皮副产物是通过增值工艺生产明胶的合适原料。
