中国沿海主要牡蛎养殖品种的营养品质和风味特征比较分析

Comparative analysis of nutritional components and flavor characteristics of cultivated oyster from different coastal areas of China

为了给牡蛎肉深加工及综合利用提供具有应用价值的基础数据,系统地探讨了中国主要养殖区新鲜牡蛎食品化学特性的差异性。结果显示,不同养殖海域及不同品种牡蛎的粗蛋白、脂肪、灰分、糖原和牛磺酸含量均具有显著差异(P<0.05)。牡蛎中锌(Zn)含量最高,各金属元素含量具有显著的地域差异性(P<0.05),其中汕头牡蛎的锌、铜(Cu)、镉(Cd)和铅(Pb)含量均显著高于其他样品(P<0.05)。呈味物质特征表现为,呈味氨基酸含量丰富,核苷酸及其关联化合物和甜菜碱含量均具有较强的地域和品种间差异性(P<0.05),其中甜菜碱含量呈"南低北高"的特征,品种间差异表现为香港牡蛎含量最低,福建牡蛎最高。醛类是新鲜牡蛎特征气味的重要组分,各地区牡蛎中检出的气味物质数量和种类有所不同;关键风味物质(ROAV≥1)中,1-辛烯-3-酮是汕头牡蛎最关键风味物质,而其他牡蛎中(E,Z)-2,6-壬二烯醛对风味贡献最大。综上,不同地理群体牡蛎的一般营养成分、牛磺酸、呈味物质和气味成分差异性显著。

In order to provide basic data for intensive processing of oysters,we compared the nutritional components and flavor characteristics of cultivated oysters from different coastal areas of China.Results show that the contents of nutrient substances in the oysters,including protein,fat,ash,glycogen and taurine,were significantly different(P<0.05).It is found that the Zn content in the oysters was the highest among all the detected elements which had significant regional difference(P<0.05).The contents of Zn,Cu,Cd and Pb in the oysters from Shantou were significantly higher than those from the other areas(P<0.05).For the taste-active components,there were abundant delicious free amino acids,flavor-enhancing nucleotides and betaine in the oysters,most of which showed significant difference in different areas and among varieties(P<0.05).The betaine content in the oysters from the north was generally greater than those from the south(lowest in Crassostrea hongkongensis but highest in C.angulata).The main flavor components of oysters from different sea areas were significantly different,and the key volatile flavor compounds(relative odor activity value,ROAV≥1)were aldehydes.Among them,1-octen-3-one showed the greatest contribution to the overall flavor of oysters from Shantou,but(E,Z)-2,6-nonadienal was the most important flavor substance in the oysters from the other sea areas.It is revealed that significant difference existed in the contents of nutrient composition,taurine,taste substance and volatile flavor composition in oysters from different regions(P<0.05).