通过以0.0、0.5、1.2、2.4、4.8、12.2mg/kgT-2毒素微胶囊毒饵料20d染毒凡纳滨对虾,采用感官评价、理化分析及显微观察法测定T-2毒素对凡纳滨对虾肌肉品质特性和自溶作用强度的影响。结果表明,T-2毒素暴露对生鲜对虾色泽具有显著性影响(P<0.05),通过理化分析得出低剂量作用时对虾肌肉硬度和咀嚼性明显升高(P<0.05),随后肌肉组织硬度、弹性、内聚性、胶黏性和咀嚼性显著降低(P<0.05);肌肉蒸煮损失率呈现先下降后上升趋势,显微结构观察肌纤维间隙不断变大,肌纤维密度下降,肌纤维碎片不断增加,肌肉品质劣化。随T-2毒素暴露剂量升高,氨基态氮溶出量逐渐降低、可溶性蛋白溶出量先升高后降低,可溶性固形物的溶出量显著增加(P<0.05),肌原纤维长度呈现显著性下降(P<0.05),扫描电子显微镜下观察肌原纤维断裂严重,自溶强度增加。
Varied doses of T-2toxin(T-2),namely0.0(control),0.5,1.2,2.4,4.8,12.2mg/kg,were orally administered to the white shrimp Litopenaeus vannamei for20consecutive days.The quality characteristics and autolysis of shrimp muscle were investigated by sensory evaluation,physicochemical analysis and microscopic observation.The results indicated that T-2exposure significantly affect the color of shrimp muscle.T-2exposure at low dose could result in a significant increase in hardness and chewiness(P<0.05),but a significant decrease in hardness,elasticity,cohesiveness,glueyness and chewiness at high dose(P<0.05).The cooking loss of shrimp muscle first rose and then decrease.Microscopic examination revealed loosening and fragmentation of muscle fibers and wider gaps between muscle fibers,suggesting a decline of shrimp muscle quality.Increasing T-2exposure resulted in a decrease in amino nitrogen content and an increase in soluble solid content.Soluble protein in shrimp muscle hydrolysate increased first and then decreased(P<0.05).Myofibril length showed a significant decline with the increase in T-2(P<0.05).Electron microscopy confirmed fracture and dissolution of myofibrils,suggesting increased autolysis.