The static viscoelasticity and consistency of several processed and natural cheese (Gouda and Cheddar) were measured by means of four kinds of rheometer or consistometer, i.e. parallel plate viscoelastometer, cone-penetrometer, micro-penetrometer and sectilometer.From the analysis of the results by means of the four-element mechanical model, we obtained the instantaneous elasticity (E1), retarded viscosity and elasticity (η2, E2), flow viscosity (η3) and retardation time τ for cheese, respectively. The viscosity of cheese ranged from 107 to 108 poises, the shear rigidity ranged from 105 to 106dynes/cm2 and the retardation time ranged from 200 to 500sec, at room temperature.In the cases of viscoelastometer by shear creep and micro-penetration method, both the logarithmic relation between the creep compliance J (t) and the time scale t could be reduced to a master creep curve by the shift along the axis of time scale at the temperature ranging from 5 to 45°C. It is seen, therefore, that the cheese has the behavior of rubbery elasticity and is thermorheologically simple in the narrow range of temperature.The yield value can be obtained for the same cheese by using a cone-penetrometer which has cones of various angle and weights. The yield value of cheese is about 2×105dynes/cm2 at 29°C and is constant independent of cone angle or weights. Cone-penetrometer and sectilometer can not measure the elastic constant, but are useful for measurements of consistency of cheese. Under a certain condition of measurement, both the logarithmic plots of the degree of sectility Ps and micro-penetration Pm are represented by a straight line.
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