The Influences Of Emulsifying Salts On The Properties Of Casein Micelles And The Cheese Model In Simplified System

The production process of processed cheese and analog cheese are very complicated, with the influence of the type and amount of emulsifying salts the most important. Studying the action mechanism of emulsifying salts on the casein micelle has guiding significance on the production of processed cheese and analog cheese. Herein, five commonly used emulsifying salts, namely, sodium citrate, sodium hexametaphosphate, sodium pyrophosphate, sodium hydrogen phosphate and sodium phosphate polymer, are used in this subject. The effects of different emulsifying salts on the physical properties of casein suspension were first studied, then the technological parameters of cheese model in simplified system were optimized. On this basis, the influences of different emulsifying salts on the structures of cheese model in simplified system were investigated.The amount ratio of emulsifying salts to the casein was set as 0,0.1%,0.3%,0.5% and 0.7% through turbidity tests. The tests of conductivity, the molar ratio of Ca to P, the acid-base titration, the foamability and emulsibility were used to investigate the influences of different emulsifying salts on the physical properties of the casein. Results show that the reaction products of different emulsifying salts with the casein were different, as well as the chelating ability with Ca. Sodium pyrophosphate has strong ability of dispersing casein and chelating calcium ions.With the grease precipitation and sensory evaluation score as the evaluation indicatior, the best addition amount was determined through single factor and orthogonal experiments. Results show that the cheese produced by adding 25g of casein,20g of butter and 45g of water has the highest grade of sensory evaluation based on 100g cheese, in accordance with national standard of cheese.The electron microscope shows that the fat balls of the cheese produced by adding sodium citrate were homogeneous, suggesting its high ability of deliquescence. The cheese produced by adding sodium hexametaphosphate has the lowest ability of precipitating grease. The cheese produced by adding sodium citrate has the minimum hardness, while the cheeses produced by adding sodium hexametaphosphate and sodium phosphate polymer have the maximum hardness. The cheese produced by adding sodium pyrophosphate has the best elastic ability, with the cheese produced by adding sodium citrate the opposite. The cheese produced by adding sodium citrate has the best cohesive quality, while the cheeses produced by adding sodium pyrophosphate, sodium hexametaphosphate and sodium phosphate polymer have little difference in cohesive quality.