ASSESSMENT OF COHESION IN GRUYERE-TYPE CHEESE BY RHEOLOGICAL METHODS

The quantitative assessment of cohesion in unripened hard cheese was studied using static methods (uniaxial compression and tension, 3-point bending, and cutting) and transient methods (stress relaxation and creep). The two levels of cheese cohesion (denoted as weak and strong, according to the judgement of the cheesemaker) were obtained by two different manufacturing procedures. Statistical analysis showed that all static methods can be used to discriminate various levels of cohesion. Uniaxial tension proved to be the most powerful test to assess quantitatively the cohesive properties of hard cheese since the values of all parameters (fracture stress, fracture strain, work to fracture, modulus of deformability, and apparent flow modulus) depend significantly (α < 0.01) on the level of cohesion. Stress relaxation and creep tests were not as powerful as the rapid static methods in distinguishing the two levels of cheese cohesion.