Stability of enzymes to temperature and high hydrostatic pressure.

Transfer of compression heat during HP processing results in temperature gradients and thus possibly to an inhomogeneous process impact on temperature sensitive products. The current temperature sensors do not allow this temperature distribution to be detected easily. Specific wireless sensors, presssure temperature time indicators (pTTIs) could offer a solution in this matter. Based on the pressure-temperature sensitivity of their inactivation, enzymes have been put forward as candidate pTTIs. A profound insight in the inactivation kinetics can be applied as a basis for the design of enzyme-based indicator systems that allow to evaluate the impact of a preservation process on quality and safety. In practice (and in case of extrinsic indicators), the stability of the enzyme is often adjusted by changes in its environment in order for it to match that of the target index better. Besides pH and ionic strength, also water availability (either by reduction of moisture content or by addition of sugars and polyalcohol) can be adjusted to reach this goal.

Keywords:Enzyme, Pressure, Solvent, pTTI, Kinetics, Impact

Disciplines:Food sciences and (bio)technology