姜汁对太平洋牡蛎（Crassostrea gigas）酶解液风味改善的研究

通过感官评价、顶空固相微萃取与气相色谱-质谱联用技术（solid phase micro-extraction gas chromatographmassspectrometer，SPME-GC/MS）以及计算相对气味活度值（ralative odour active value，ROAV）的方法分析太平洋牡蛎（Crassostrea gigas）酶解前后挥发性成分的变化情况，探讨姜汁对牡蛎脂质氧化的抑制作用和改善牡蛎酶解产物风味的效果。结果表明：与新鲜牡蛎相比，酶解液中脂质氧化产物，如异戊醛、壬醛、2-壬烯醛和3,5-辛二烯酮含量分别增加至5.09%、1.6%、1.3%、0.5%，使牡蛎酶解液呈现出较重的腥味与哈喇味，说明牡蛎风味的劣变与酶解过程中发生的脂质氧化有关。牡蛎酶解过程中添加姜汁，脂肪氧化产生的不愉快成分如（E）-2-戊烯醛、（Z）-4-庚烯醛、壬醛、2,3-辛二酮等未被检测到；异戊醛、己醛、（E）-2-己烯醛等物质的相对含量分别减少了81.02%、33.28%、54.39%。姜汁中挥发性成分如香叶醇、香茅醇、对伞花烃和芳樟醇等成为其新的主体呈味成分，并贡献出花香、柠檬香等愉快气味。因此，姜汁对改善牡蛎酶解液的风味有显著效果。

Effect of Fresh Ginger Juice on Flavor Improvement of Oyster (Crassostrea gigas) Hydrolysates

The change in the composition of volatile components in Crassostrea gigas before and after hydrolysis was
analyzed according to sensory evaluation, SPME-GC/MS analysis and ROAV (relative odor activity value). The effect of
ginger juice on lipid oxidation and flavor of oyster hydrolysates was studied. The results showed that the relative contents
of lipid oxidation products such as pentatal, 3-methyl-butanal, heptatal, (E)-2-nonenal, (Z)-4-heptenal and 3,5-octadien-
2-one, which were responsible for fishy and fatty odor, were increased to 5.09%, 1.6%, 1.3% and 0.5%, respectively. The
unpleasant smell of oyster protein hydrolysates might be mainly related to lipid oxidation during hydrolysis. However, after
addition of ginger juice, the unpleasant-odor compounds derived from fat oxidation such as trans-2-pentenal, nonanal, (Z)-4-
heptenal, and 2,3-octanedione were not detected. Meanwhile, the contents of 3-methyl-butanal, hexanal, and trans-2-hexenal
were reduced by 81.02%, 33.28% and 54.39%, respectively. The major volatile components of ginger such as geraniol,
citronellol, citral, p-cymene and linalool were detected in oyster protein hydrolysates, which contributed to the flowery,
lemon and orange flavor of the hydrolysates. Therefore, ginger juice had a significant contribution to the flavor improvement
of oyster hydrolysates.