The effect of protein unfolding stability on their rates of irreversible denaturation

The rate at which proteins denature irreversibly is related to their conformation stability. This relationship is examined in detail using a two-stage model and numerical simulation. The results are discussed along with proposals for controlling globular protein irreversible denaturation. The rate of irreversible structure change depends on the Gibbs free energy for protein unfolding (Delta G(U(T))) and the rate of at least one irreversible, terminal reaction. Delta G(U) depends on the protein, molecular weight (M-w), mid-point temperature (T-m) and heat capacity change (Delta Cp) for unfolding. The quantitative two-stage model applies to protein structural changes likely within non-ideal systems such as concentrated, low moisture, anhydrous, multiphasic or heterogeneous foods. (C) 1998 Elsevier Science Ltd. All rights reserved.