Dynamic model system to study the kinetics of thermally-induced syneresis of cheese curd grains

A dynamic model system for the observation of the 3-dimensional syneresis of cheese curd grain during cheese making was developed to study the influence of temperature in a range from 20 to 80 degreesC on the grain structure. The syneresis of grains prepared by cutting a rennet skim milk gel into small defined cubes rises when the temperature increases. But, above 50 degreesC no further increase of the syneresis is achieved, since skin formation obstructs the running out of whey from the cheese curd grains. For temperatures between 20 and 50 degreesC the syneresis was able to be described by a formal kinetic model and an activation energy of approximately 100 kJ/mol was estimated. The value of the activation energy suggests that chemical linkage reactions may be responsible for the shrinking of the grains and promote syneresis. The dynamic system developed allows a defined investigation of factors influencing the syneresis of cheese curd grains and their modelling.