Abstract
Summary: Microwave attenuation properties of frozen fish muscle exhibit a time dependence, falling in value over periods of 1–3 weeks. This reduction of attenuation is due to gradual accretion of ice in the frozen system at the expense of unfrozen water. More than one exponential component is observed in the overall change and at least two are seen. These are both thermally activated and the activation energies for the characteristic time constants lie in the range 32–49 kJ mol−1. This is similar in value to activation energies for diffusion through dehydrated and frozen systems (after recalculation of the latter published data). An explanation is offered which takes this into account.