| Abalones are members of a large class, Gastropoda, of mollusks, naturally occurring in all oceans of the world. In China, more and more people enjoy this shellfish, since its traditional culture history, unique taste and nutrition. Recently, the enlarging of abalone aquiculture and output are remarkable. It indicates an optimistic future of the abalone market. Drying is the main processing method of abalone in Asian countries. In this paper, raw abalone was dried and then restored water, eventually became water restored abalone. During this circular processing, the structure and rheological property changes of abalone were studied, and the quantitative correlation between rheological properties and characteristic values of structure for abalone was also studied.1. Selecting sun drying and hot-air drying for abalone's drying method, because the former is the traditional drying method and the latter is widely used in modern industry. The drying dynamics and dried abalone's quality of this two drying method were compared. The results show that the two methods had a similar process: a short-time rising rate period and following a falling rate period. Shrinkage ratio of these two dried abalone were reached 80%. When drying processes were finished, hot-air drying just cost half of the time of solar drying. Both of the two abalones had significant increase comparing to boiled abalone in the content of delicious amino acids (DAA), furthermore the hot-air dried abalone had a bigger advantage than the solar dried abalone in DAA and AMP content. The color of hot-air dried abalone was tan and bright, but solar dried abalone was white partially. The microstructure of these two dried abalone meat had significantly differences: muscle fiber of solar dried abalone was shrank equably and compactly, while the fiber of hot-air dried abalone was distorted badly and appeared lots of big holes.2. Using histological method (Van Gieson staining) and rheological test method (stress-relaxation and rupture strength measurement) to study the structural and rheological properties of abalone meat during the process of water restoration. Firstly, the optimal water restoration condition were confirmed as following, NaCO3 concentration is 5%, lye dunk time is 24h, boiled time is 40min, water dunk time is 4d. During the water restoration process, the mass, volume and water content and of dried abalone were increased persistently, the ash, protein and collagen content were decreased. The restored water sun dried abalone had higher water content and more solids loss than sun dried abalone, but they had approximate collagen content. Through the result of histology structure observe, it was found that, during the water restoration process, the muscles fibrils became more dispersedly, voids among muscles fibrils expanded, and finally the restored water abalone'muscles fibrils had a loose network structure, and the restored water sun dried abalone had more larger voids than sun dried ones. It was indicated that the rheological parameters (E0,τ1,η1 and rupture strength) changed gradually with structure of muscle fibrils and water content. The adductor muscles of abalone had orientation property, so the rheological parameters were affected by muscles fibrils. At the cross section of muscle tissue, the elasticity component and rupture strength decreased gradually, and the viscosity component decreased firstly and then increased. At the vertical section, the changes of rheological parameters were accordant with the cross section but the elasticity component, which increased a little and then came full circle. The foot muscle structure were un-orientation property, so the rheological parameters were affected by water content and loss solids. As a whole, the elasticity component and rupture strength decreased, the viscosity component increased, fluidness enhanced.3. Contrast of physical chemical properties in raw, cooked and restored water abalone were studied. It was found that, the mass, volume, water content of cooked abalone were less than restored water abalone'; the flavor component was more than the latter; but the nutrition component, such as mucopolysaccharide, were more than the latter. Restored water abalone'mass, volume, water content were higher than raw abalone; the flavor component were less than raw abalone; the nutrition component, such as mucopolysaccharide, taurine, were less than raw abalone's. Raw abalone's muscles fibrils were slender, compact, netlike, and voids among fibrils were small and equably. Restored water abalone's myofibrils were agglomerate, and muscles structure were loose and disrepair. Using image processing and analysis technique, the characteristic values of structure for abalone was studied. The distance between myofibrils of raw abalone was larger than cooked and restored water abalone'. The ratio of total muscle fibrils in full image domain of raw abalone was 5~7% more than restore water abalone'. The ratio of total voids in full image domain of restored water abalone was above 40%, higher than raw and cooked abalone.The elastic modulus and rupture strength of raw abalone were higher and mechanical parameters are un-equably; the viscous modulus and relaxation time of restored abalone were higher and mechanical parameters are equably.
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