Study On The Cryoprotective Effect Of ?-cyclodextrin/ovalbumin Complex Cryoprotectant On Culter Alburnus

Culter alburnus are widely distributed in the freshwater basin in China and it is a medium-sized economic fish with high economic benefits.In recent years,with the gradual development and maturity of the cultivation technology of culter alburnus and affected by the relative concentration of the fishing season,high-yield culter alburnus have exceeded the demand of the market in the current season.Therefore,freezing storage methods are often used to preserve the culter alburnus.However,frozen storage will cause irreversible quality deterioration of the culter alburnus.Adding traditional commercial cryoprotectants will bring the shortcomings of high sweetness and high calories to the product.In this article,the research object of this article is to use?-cyclodextrin(?-CD)and Ovalbumin(OVA)as cryoprotectants materials to study the cryoprotective effect of?-cyclodextrin/Ovalbumin(?-CD/OVA)complex at different concentrations(0,2,4 and 6%)on fish meat,myofibrillar protein and myofibrillar protein gel to provides a specific reference basis for screening the optimal concentration of green commercial cryoprotectants.The main research contents and results are as follows:1.Using?-cyclodextrin and ovalbumin as raw materials,explore the best quality ratio of the two compounds.The results show that when the mass ratio of?-cyclodextrin and ovalbumin is 1:3,the minimum turbidity and particle size of?-CD/OVA(1:3)composite system are 0.101 and 91 nm,respectively and the maximum absolute value of the potential is 8.17 m V.The TEM observation results show that?-CD/OVA(1:3)has the best dispersion degree under this ratio,and it has better dispersion stability.The DSC analysis results also show that the thermal denaturation temperature of the?-CD/OVA(1:3)complex system at this ratio is 62.7?,and the thermal stability is the best.Therefore,?-CD/OVA with a mass ratio of 1:3 is selected as the complex cryoprotectant for culter alburnus is more suitable.2.To study the cryoprotective protection effect of?-CD/OVA(1:3)complex cryoprotectant at different concentrations(0%,2%,4%and 6%)on fish meat.The results show that,compared with the blank group,?-CD/OVA can effectively delay the quality deterioration of fish during frozen storage.?-CD/OVA effectively inhibits the decrease of fish whiteness,water holding capacity and hardness,delays the rising trend of pH,TBARS value and TVB-N value,slows down the spoilage of fish meat,and improves the water retention capacity of fish meat.The microstructure of fish meat was further observed by tissue section and SEM,and it was found that 6%?-CD/OVA has obvious cryoprotective protection effect on fish meat.The internal tissue structure of fish with 6%?-CD/OVA treatment is tightly arranged during the freezing period.,the muscle fiber structure is intact,and there is no obvious rupture of the endomuscular membrane.3.To explore the cryoprotective protection effect of?-CD/OVA(1:3)complex cryoprotectant with different concentrations(0%,2%,4%and 6%)on myofibrillar protein and the cryoprotective protection mechanism of?-CD/OVA complex cryoprotectant.The results show that the addition of 6%?-CD/OVA can effectively inhibit the polymerization and denaturation of myofibrillar protein during the freezing process,and the cryoprotective protection effect of 6%?-CD/OVA is significantly better than that of 2%and 4%?-CD/OVA.6%?-CD/OVA significantly inhibited the decrease of myofibrillar protein content,solubility and Ca²⁺-ATPase activity(P<0.05).The hydroxyl groups on?-CD/OVA molecules bind to protein functional groups through hydrogen bonds and it reduces the oxidation degree of sulfhydryl groups and effectively delays the rise of the pH and surface hydrophobicity of the system.Ultraviolet spectroscopy and endogenous fluorescence spectroscopy show that?-CD/OVA can inhibit the unfolding of the polypeptide chain structure,thereby effectively protecting the stability of the tertiary structure of myofibrillar protein.The analysis results of the secondary structure show that?-CD/OVA effectively inhibits the transformation of?-helical structure to other structures,and improves the frozen storage stability of myofibrillar protein.4.To study the cryoprotective protection effect of?-CD/OVA(1:3)at different concentrations(0%,2%,4%and 6%)on the performance of myofibrillar protein gels.The results show that the addition of?-CD/OVA can effectively improve the gel properties of myofibrillar protein.The treatment of 6%?-CD/OVA significantly inhibited the decrease of gel whiteness and water holding capacity,delayed the rise of the relaxation time,improved the water retention capacity of gel,and significantly reduced the degradation of myosin.The results of dynamic rheological analysis show that the treatment of 6%?-CD/OVA makes the gel network structure more stable and elastic.Scanning electron microscope observation results show that the addition of 6%?-CD/OVA can promote the formation of a tighter gel network structure.