EFFECT OF MATURATION ON LARGE-DEFORMATION AND FRACTURE PROPERTIES OF (SEMI-)HARD CHEESES

Some general aspects of large deformation and fracture behaviour of se mi-hard and hard cheeses are discussed with special emphasis on change s due to maturation. Fracture properties are shown to be much more dep endent on large inhomogeneities than the resistance against small defo rmation (the modulus). The modulus increases during maturation, primar ily due to the decrease in water content. Fracture properties are affe cted by the drying up of the cheese as well as by proteolysis. These f actors not only affect fracture stress and strain directly, but also i ndirectly by influencing energy dissipation during the deformation and fracture process. The latter may cause the dependence of fracture str ain on the rate of deformation to be different for various cheeses.