不同养殖模式及规格大黄鱼品质特征分析??*

Characterization of large yellow croaker quality in different culture modes and sizes

中文关键词: 大黄鱼  养殖模式  规格  品质  风味

英文关键词: Large yellow croaker  Culture modes  Sizes  Quality  Flavor

中文摘要:

      为了探究养殖模式对大黄鱼（Larimichthys crocea）品质的影响，通过对通框网箱、深水网箱和工船养殖的大规格（500 g～550 g）和小规格（250 g～330 g）大黄鱼形体、质构、基本营养成分、氨基酸、脂肪酸、滋味轮廓和挥发性气味进行测定，通过正交偏最小二乘法判别分析综合评价了上述指标的差异。结果表明：工船养殖大黄鱼的体形优于深水和通框网箱养殖大黄鱼；相同规格工船和深水网箱大黄鱼的硬度、粘附性和胶粘性高于通框网箱；不同养殖模式大规格大黄鱼粗脂肪含量低于小规格；工船养殖和深水网箱大黄鱼单不饱和脂肪酸含量显著高于通框网箱；工船养殖大黄鱼具有较高的鲜味和甜味，深水网箱养殖大黄鱼丰富度较高；小规格大黄鱼异戊醛、2-蒎烯、丙烯酸乙酯、2-丁酮和丁醛-D等含量要高于大规格大黄鱼；正交偏最小二乘判别分析筛选出反油酸、2-丁醇-M、丁醛-M、鲜味、涩味回味、丰富度、蛋氨酸和半胱氨酸是区分不同养殖模式大黄鱼的重要指标。综上所述，工船养殖和深水网箱等新兴养殖能提高大黄鱼体形、质构和滋味，反油酸、2-丁醇-M、丁醛-M、鲜味、涩味回味、丰富度、蛋氨酸和半胱氨酸可用于不同养殖模式大黄鱼的区分。

英文摘要:

      Large yellow croaker (Larimichthys crocea) is a major marine aquaculture aquatic product in China with a highest product among marine aquaculture. In China, large yellow croaker is mainly farmed in nearshore floating cages, but the irrational layout of nearshore aquaculture and the high aquaculture density seriously affected the quality of the flesh. Offshore aquaculture, such as deep-water cage and offshore ship, has the advantages of a wide area and good water quality, the quality of large yellow croaker cultured in offshore systems has been significantly improved. Nevertheless, instances exist in which large yellow croaker raised in nearshore floating cages may be misrepresented as being cultured in offshore systems, likely motivated by the higher market value associated with offshore cultivated large yellow croaker. In order to avoid the occurrence of the above phenomenon, it is necessary to investigate the quality characteristics of large yellow croaker cultured in different modes and screen the representative indexes which can be used to distinguish large yellow croaker cultured in different modes. In order to analyze the quality differences between large yellow croaker cultured in offshore and nearshore modes, fish reared in deep-water cage, floating cages and offshore ship system with large-size (500-550 g) and small-size (250-330 g) were collected from October to November in 2023. Among them, the deep-water cage and floating cages were fixed in the Sandu Bay of Ningde City, Fujian Province. For offshore system, fish was cultured in Guoxin 1, which shifted between Ningde and Qingdao Sea area. After collection, the morphology, texture, basic nutrients, amino acids, fatty acids, taste profile, and volatile compounds odor of flesh were analyzed. The results showed that: (1) morphology of large yellow croaker reared in offshore modes was better than nearshore mode with lower condition factor and higher body length/height, caudal peduncle length/height. And the condition factor and body length/height ratio of large yellow croaker with large size were lower than those of small size in the same culture mode. (2) The hardness, adhesiveness, and stickiness of large yellow croaker from offshore ships and deep-water cages were higher than those from floating cages with same sizes. For fishes from same culture mode, the hardness, adhesion and chewiness of large large yellow croaker were higher than that of small large yellow croaker. Springiness of large yellow croaker cultured in floating cages with small size were significantly lower than those of other fish. (3) The crude fat content of large yellow croaker with large sizes was lower than that of fish with small sizes across different farming modes. For large yellow croaker with large size, the crude fat content of fish cultured in floating cages was significantly higher than that of the other two culture modes, and is lowest in offshore ship system. Fish culture in offshore ship system has lower protein level that of the other two culture modes. In the same culture mode, the ash content of large yellow croaker with small size was lower than that of large size. The moisture among the fish was almost same. Nutritional evaluation of amino acids suggested that limiting amino acid of large yellow croaker with small size is ILE, while limiting amino acid of large yellow croaker with large size is MET and CYS. The monounsaturated fatty acid content of large yellow croaker reared in offshore ships and deep-water cages was significantly higher than that of fish reared in floating cages. EPA and DHA of large yellow croaker were significantly higher in deep-water cage and offshore ship system than in floating cages. (4) IMP contributes higher to the flavor of large yellow croaker among different flavor nucleotides. And in same culture mode, IMP content of large yellow croaker with large size was significantly higher than that of small size. Large yellow croaker reared in offshore ships exhibited higher umami and sweet tastes, while those reared in deep-water cages showed higher richness. Large yellow croaker culture in floating cages had higher levels of 2-methylbutyraldehyde, 2-methylpropionaldehyde, isopropylidene acetone, acetone, 2-hexanone, 2-pentanone, ethyl caproate, and methyl acetate than other two modes, and which show a richer volatile flavour. The contents of isovaleraldehyde, alpha-pinene, ethyl acrylate, 2-butanone, and butanal-D were higher in large yellow croaker with small size than in large size, showing a more intense fruity flavour. Orthogonal partial least squares discriminant analysis identified methyl trans-9-octadecenoate, 2-butanol-M, butanal-M, umami, astringent aftertaste, richness, methionine, and cysteine as important indicators for distinguishing large yellow croaker reared in different culture modes. In summary, emerging culture modes such as offshore ship and deep-water cage is a good way to improve the quality of of large yellow croaker by improving the body shape, texture, and taste of fish.Elaidic acid, 2-butanol-M, butanal-M, umami, astringent aftertaste, richness, methionine, and cysteine can be used to distinguish large yellow croaker cultured in different modes.