Control of water in foods during storage

Abstract Moisture content and its water activity ( a w ) are critical parameters affecting the shelf life of most food products. In most cases excessive amounts of water will cause spoilage, while in other cases loss of water will render foods unacceptable. The control of water in foods requires knowledge of their sorption/desorption behavior, critical moisture content, the environmental storage conditions of temperature and relative humidity, packaging parameters including volume to area ratios and permeability. Fast and reliable methods of evaluating the above parameters are needed to predict the storage life of foods. The importance of moisture control in produce as well as in dry products is discussed. Fast methods to evaluate water sorption/desorption behavior of foods are described. A computer program, which integrates all parameters required to predict the water dependent shelf life of foods, including changing conditions during storage, is also reported.