Effect Of Sodium Chloride And Sodium Tripolyphosphate On Gelation Properties Of Pressure-induced Chicken Meat Products

Sodium chloride and sodium tripolyphosphate are used very commonly as additives in meat products,while their dosage and effect have been widely focused.Concern about health problems caused by the excessive salt intake,the demand for low-sodium meat products grow with a great speed.Pressurized meat products as a new kind of meat product has huge market potential and welcomed by consumers.Using application of high pressure processing to reduce the salt content in meat products could not only maintain the nutrition of food and flavor,but also lead protein denaturation and gelation.Also with the inactivation of enzyme,the shelf life of products extend.Marinating excellent protein processing characteristics and improving the quality of the products would be great significances to meat production.In this study,in order to reduce sodium content,fresh chicken breast as raw materials,added different concentrations of sodium chloride and sodium tripolyphosphate,determined its physicochemical properties.Heat-induced gel supplemented with sodium chloride or sodium tripolyphosphate as group of control.On the base of these experiments above,structure change of molecules were studied with appropriate proportion of sodium chloride and sodium tripolyphosphate in products treated by different levels of high pressure.Explored the degeneration tendency of protein and changes of hydrophobicity and molecular changes.The results of experiments could provide theoretical basis for pressure-induced ready to eat gel-type meat products.All the specific researches and results were as follows:1 Effect of sodium chloride in pressurized gel-type chicken meat productsFresh chicken breast meat was chopped homogeneous,mixed with different concentration of salt.After pressure treatment,measured on color,water holding capacity,texture properties,microstructure and secondary structure changes of protein.With salt addition increased,the whiteness of pressurized meat products increased and generally higher.Water loss was also decreased,texture characteristic differences were not significant more than 1.2%sodium chloride.Microstructure revealed the addition of salt more than 1%in pressurized meat products already had stable microstructures and the pore radius were smaller and more uniform.Then a-helix content of pressure-induced gel group decreased along with the increasing salt concentration,while ?-sheet content increased.The additive amount of salt increasing obviously improved the gel properties of meat products by using high pressure processing.Assisted with high pressure for 600MPa at 40? for 5minutes,sodium chloride content could be reduced to 1.2%in pressure-induced ready-to-eat gel-type meat products.2 Effect of sodium tripolyphosphate in pressurized gel-type chicken meat productsFresh chicken breast meat was chopped homogeneous,mixed with different concentration of sodium tripolyphosphate with 1.2%sodium chloride.After pressure treatment,measured on color,water holding capacity,texture properties,microstructure and secondary structure changes of protein.Compared the groups of pressure-induced gels with heat-induced gels.With the increase of sodium tripolyphosphate,the whiteness meat products augmented.The gel water loss increased but decreased after 0.1%.The microstructure also showed the more the addition of sodium tripolyphosphate,the thinner of gel network line.a-Helix content of pressurized gel group decreased while ?-sheet content increased.All the results indicated the additive amount of sodium tripolyphosphate increased,obviously improved the gel properties of meat products by using high pressure processing with 600MPa at 40? for 5minutes.Based on the 1.2%sodium chloride addition,sodium tripolyphosphate could be reduced to 0.1%in pressure-induced ready-to-eat gel-type meat products.3 Effect of different pressure levels on the structure and interaction of protein molecules in low salt gelation of chicken meat Studied on different pressure of different pressures at 40? for 5minutes,two groups of 1.2%sodium chloride added and 1.2%sodium chloride with 0.1%sodium tripolyphosphate added as samples to explore the interaction of protein molecules.Determined of hydrophobicity,molecular interaction force,SDS-PAGE and differential scanning calorimetry.With the increase of pressure,the hydrophobicity and sulfhydryl activities increased.The high pressure processing promoted unfolding of myosin and denaturation of protein.The results showed that low-salt pressure-induced gel could keep the good balance with protein-water molecule,protein-protein molecule in myofibrillar protein system to get a uniform structure.