I. Ludikhuyze et al., Combined pressure-temperature inactivation of alkaline phosphatase in bovine milk: A kinetic study, J FOOD SCI, 65(1), 2000, pp. 155-160
A detailed kinetic study on pressure-temperature inactivation of alkaline p
hosphatase has been performed in the pressure range 0.1 to 725 MPa at tempe
ratures between 25 and 63 degrees C. Inactivation could be accurately descr
ibed by a first order kinetic model, allowing D-values to be calculated. Ac
cording to the thermal death time terminology, z(T)- and z(P)-values were c
alculated, expressing temperature and pressure dependence respectively. How
ever, at high temperature, pressure dependence could not be calculated unam
biguously. D-values firstly increased with increasing pressure up to 300 MP
a and then decreased with further pressure increase, showing thermal inacti
vation to be counteracted by low pressure. Finally, a global model describi
ng the D-value as a function of pressure and temperature has been formulate
d.