Study On The Tissue Structure And Texture Of Abalone (Haliotis Discus Hannai Ino)

Abalone(Haliotis discus hannai Ino), belonging to Gastropoda, is a kind of precious marine animal. Abalone muscular foot, the edible part of abalone, changes significantly in quality during heating treatment. Meanwhile, along with the rapid development of "Northern abalone farming in the south" maricultured method, abalone production increased year by year. Therefore, the refine and further processing of abalone became an emphasis in recent research.Abalone muscular foot were investigated by conventional instruments, microscope and texture instrument. The nutrient components, tissue structure and textural charateristics of abalone were monitored and the differences of different parts of abalone meat were compared and analyzed. The results indicated that moisture, crude protein, collagen and the number of collagen fibers gradually increased while the number of muscle fibers gradually increased from the middle to the verge of muscle. The moisture percent of raw samples and protein and collagen percent of the drying samples from the verge of abalone meats were 83.90%, 80.20% and 37.50% respectively. What is more, hardness, chewiness and resilience of the joint muscle were significantly higher than those of the middle muscle, but the springiness was lower.To ascertain quality changes regularity, abalone muscular foot were heated at 50,60,70, 80,90,100℃ for 1 h and the changes of the nutrient components, microstructure and textural parameters were examined. The results showed that the mass loss of abalone meats increased with the increasing temperature, and the loss ratio reached 23% at 100℃. With the increase in temperature, the ash content decreased gradually, and the total sugar content increased firstly and then decreased, which reached the maximum at 80℃. Shrinkage of muscle fiber and increase of the intermyofibrillar gap were observed with the increasing temperature. Besides, shear force, hardness and chewiness increased firstly and then decreased from 50 to 100℃, and the greatest shear force was achieved at 70℃. Springiness, cohesiveness and resilience increased obviously from 50 to 70℃, thereafter which reached plateau. The study demonstrated that the quality of abalone muscular foot changed significantly after heating treatment at different temperatures. The loss in water-soluble components and shrinkage in the muscle fiber can increase the shear force and the hardness, but the loss in water-dissoluble components and the breakdown in muscle fiber can increase the tenderness and decrease the hardness.Single-factor experiments were conducted to establish correlation between heating treatment conditions and abalone products quality and to ascertain that heating treatment influenced tissue structure, tenderness, hardiness, springiness, cohesiveness, chewiness, resilience and sensory of abalone muscular foot. The results indicated that high heating treatment (>90℃) resulted rapidly in fragment of muscle fibers, and an increase in gaps between myofibrillar material. The optimized condition in texture was deemed to be heated at 80℃ for 1-14 h. And there were no significant difference at low temperatures. So the optimized condition in quality was determined to be heated at 80℃ for 1-6 h. In this region, heating treatment showed less loss in mass and positive results by modifying structure and the textural characteristics of tenderness, hardness, cohesiveness, springiness and chewiness.