Evaporative weight loss in the food cold chain can lead to both significant loss of product quality (and hence value) and to the loss of saleable weight. During cold storage of many food products, heat transfer processes are fast relative to the required heat of vaporization, so weight loss can be modelled by a simple model of convective mass transfer from the surface of the product in the gas phase. Measured data from the literature was used to validate the model by assessing whether the rate of weight loss was proportional to the partial pressure driving force for data measured for the same product and packaging stored in similar cold storage facilities. The trends in rate of weight loss were close to linear (R~2 > 0.90) for most data suggesting that the simple model was adequate for a wide range of products and storage situations. The model indicates that for cold storage the most cost-effective options to reduce weight loss are colder storage temperatures, high air relative humidity and tighter temperature control. Lower air velocity also reduces weight loss but the effect may not be as significant as anticipated dues to the convective resistance being small, relative to packaging or product skin resistances to mass transfer. Packaging films reduce weight loss but must be tight-fitting to avoid moisture transfer between the product and packaging "headspace", and thus within package frosting or condensation, when there are temperature fluctuations.
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