Changes in rheological and viscoelastic properties and protein breakdown during the ripening of Port Salut Argentino cheese

BERTOLA, NORA; BEVILACQUA A.; ZARITZKY NOEMI.

INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 1991 vol. 26 p. 467 - 478

0950-5423

Changes in the rheological behaviour and viscoelastic properties during ripening at 10°C of a soft cheese (Port Salut Argentino) packaged in a plastic film (EVA-EVA) were analysed. Casein degradation was measured by electrophoresis dab gels; alfaS1 casein degradation was rapid and striking compared with that of beta casein. Rheological parameters obtained from uniaxial compression tests changed during ripening: hardness decreased, adhesiveness and cohesiveness increased.An exponential decay equation with two maxwellian elements and one elastic in parallel was fitted to characterize stress relaxation curves. Viscoelastic parameters (elastic moduli and relaxation times) were obtained using non-linear regression analysis. The elastic equilibrium modulus decreased 80% during the ripening period and the viscosity of the element with the highest relaxation time decreased 20%.These parameters represented the changes observed in cheese hardness and elasticityduring ageing time and were related to the extent of casein breakdown