The Relationship between Chemical Compositions and Body Weight of Cultured Cobia (Rachycentron canadum) of Different Growing Stages

養殖海鱺(Rachycentron canadum)成長期間化學組成與體重之關係

莊健隆(Jan-Lung Chuang) ； 林瑞堂(Ruey-Tarng Lin) ； 蕭泉源(Chyuan-Yuan Shiau)

《臺灣水產學會刊》 34卷1期 (2007/03) Pp. 21-30

https://doi.org/10.29822/JFST.200703.0003

摘要

箱網養殖之31尾海鱺(Rachycentron canadum)體重範圍自1.5至8703g，1.4 kg以下的魚，肥滿度與魚體大小呈顯著正相關(r=0.79)，以上者則無相關性。普通肉pH值介於5.5~6.3之間，類似洄游性紅肉魚類；氨與尿素亦低，和一般硬骨魚類無異，pH、氨及尿素與魚體大小皆無良好之相關性存在。海鱺之一般成分受魚體大小影響甚大，尤以脂肪和水分最為顯著，在同一魚體中，腹部普通肉脂肪含量明顯高於背部肉，甚至達2倍以上，兩者之脂肪含量皆與魚體大小呈顯著之正相關(r=0.80；r=0.78)，相對地，隨魚體重量增加，水分含量愈少，蛋白質與灰分在魚體間之差異則較小。游離胺基酸總量及其主要之胺基酸包括牛磺酸、甘胺酸、丙胺酸與麩胺酸等皆隨魚體重量之增加而有減少之趨勢，其中牛磺酸與魚體重量之負相關性最高。海鱺肉中含有雙胜肽之甲肌肽，含量介於14~80mg/100g，在魚體間差異大，但與大小卻無良好相關性。ATP相關化合物中以肌苷酸(IMP)為主，總量及IMP與體重皆無顯著之相關性存在。

關鍵字

海鱺 ； 化學組成 ； 體重 ； 成長

並列摘要

The condition factor of 31 cage-cultured cobia (Rachycentreon canadum) with body weight ranging from 1.5 to 8730 grams was significantly and positively correlated with body weight for fish below 1.4 Kg (r=0.79), while no good correlation was found among fish above 1.4 Kg. The pH value of white muscle in cobia was between 5.5 and 6.3, which was similar to that of pelagic fishes. The levels of ammonia and urea were low in cobia. This is also similar to the most teleosts. No significant correlation was found between fish body weight and pH, ammonia and urea. There were large variations in fat and moisture contents of white muscle among different size of cobia, but not in protein and ash. The fat level in the ventral meat was two times higher than that of the dorsal meat of the same fish. Fat contents of both dorsal and ventral meats were significantly and positively correlated with body weight (r=0.8 and 0.78, respectively). In contrast, moisture content decreased gradually as fish body weight increased. The predominant free amino acids (FAAs) in cobia were taurine, glycine, alanine and glutamic acid. The contents of these FAAs and total FAAs tended to decrease as body weight increased. When comparing with glycine, alanine and glutamic acid, taurine was most significantly and negatively correlated with fish size. Anserine, a dipeptide, was detected in the meat of cultured cobia, and its content ranged from 14 to 80 mg/100g; however, it was not significantly correlated with fish body weight. Inosine monophosphate (IMP) was the most prominent component of ATP-related compounds. Both ATP-related compounds and IMP had no significant correlation with fish size.

並列關鍵字

Cobia ； Chemical Compositions ； Body Weight ； Growing