不同提取方式下小黄鱼下脚料粗鱼油脂肪酸组成及挥发性风味成分的变化

Effects of Different Extraction Methods on Fatty Acid Composition and Volatile Flavor Components of Crude Fish Oil from Larimichthys polyactis Scraps

摘要:

为提高小黄鱼下脚料的高值化利用，研究以小黄鱼下脚料为试材，将其进行前处理分别制成湿样（Wet Sample，W）和干样（Dry Sample，D），采用索氏提取法（Soxhlet Extractor Method，S）及酶解法[碱性蛋白酶（1）、中性蛋白酶（2）、木瓜蛋白酶（3）]提取粗鱼油，对其理化指标进行评价、并分析其脂肪酸组成及挥发性风味成分。结果表明，7种不同提取方式（DS、D1、D2、D3、W1、W2、W3）制备的粗鱼油其理化指标值均满足水产标准（SC/T 3502-2016）三级的规定。所得粗鱼油中棕榈酸（C16:0）、硬脂酸（C18:0）、棕榈油酸（C16:1）、油酸（C18:1n9）均为主要脂肪酸，其中D1处理组粗鱼油EPA和DHA相对含量最高，为25.59%。不同提取方式所提粗鱼油中共检出99种挥发性风味成分，包括醇类16种、醛类16种、酮类15种、酯类3种、酸类8种、碳氢化合物16种、酰胺类化合物3种、杂环化合物及其他22种，其中DS处理组粗鱼油的风味与酶解法相比较差，表明冷冻干燥前处理在一定程度上改善了粗鱼油的风味。综上，采用冷冻干燥前处理结合酶解法对小黄鱼下脚料进行提取，提取得到的粗鱼油的品质优良，就其脂肪酸组成而言，多不饱和脂肪酸含量较高，因此其营养价值较高，且该处理有效改善了粗鱼油的风味，可为小黄鱼下脚料的高值化利用提供一定的理论依据与参考。

Abstract:

To enhance the value of Larimichthys polyactis scrap utilization, L. polyactis scraps were pre-processed to yield wet (W) and dry (D) samples as test materials. The Soxhlet (S) extraction and enzymatic hydrolysis methods (alkaline protease (1), neutral protease (2), and papain (3)) were used to extract crude fish oil. Evaluations were conducted on physicochemical indices, fatty acid composition, and volatile flavor components. The physicochemical index values of crude fish oil prepared by each of the seven different extraction methods (DS, D1, D2, D3, W1, W2, and W3) all met Level 3 requirements of the Aquatic Products Industry Standard (SC/T 3502-2016). The main fatty acids of the crude fish oils were palmitic acid (C16:0), stearic acid (C18:0), palmitoleic acid (C16:1), and oleic acid (C18:1n9). Among these, the content of EPA and DHA in the D1 treatment group was highest at 25.59%. In total, 99 volatile flavor components, including 16 alcohols, 16 aldehydes, 15 ketones, 3 esters, 8 acids, 16 hydrocarbons, 3 amides, and 22 heterocyclic compounds, were detected in the crude fish oils extracted using the different methods. The flavor of crude fish oil from the DS-treated group was relatively poor compared with that of the enzymatic hydrolysis methods, suggesting that lyophilization improved the flavor to some extent. In conclusion, the crude fish oil produced by combined enzymatic hydrolysis and pretreatment lyophilization was of high quality. These methods yielded elevated polyunsaturated fatty acid content, suggesting high nutritional value of these crude fish oils. These processes also successfully enhanced crude fish oil flavor, serving as a theoretical foundation and point of reference for value added utilization of L polyactis scraps.