Properties of water in foods : in relation to quality and stability

Session I. Fundamentals : high moisture systems. - Water and aqueous solutions : recent advances. - Phase separation in protein - water systems and the formation of structure. - The dipalmitoylphosphatidylcholine (DPPC) - water system. - An enzymatically modified protein as a new surfactant and its function to interact with water and oil in an emulsion system. - Session 2. Fundamentals : low and intermediate moisture systems. - The influence of soluble components on water sorption hysteresis. - Some facts concerning water vapour sorption hysteresis on potato starch. - Influence of temperature on sorption equilibria. - Development of B.E. T. -like models for sorption of water on foods, theory and relevance. - Solution thermodynamics and the starch-water system. - Session 3. Physico-chemical and enzymatic changes. - Effects of water activity and water content on mobility of food components, and their effects on phase transitions in food systems. - Enzyme activity as a function of water activity. - The influence of water content and temperature on the formation of Maillard reaction intermediates during the drying of plant products. - Polysaccharide-water interactions - thermal behavior of rice starch. - Session 4. Microbiology and water activity. - Present state of knowledge of aw effects on microorganisms. - Effects of aw and pH on growth and survival of Staphylococcus aureus. - Effect of aw on growth and survival of Bacillaceae. - Effect of water activity on mold growth and mycotoxin production. - The antimicrobial activity of sugar against pathogens of wounds and other infections of man. - Hurdle technology applied to meat products of the shelf stable product and intermediate moisture food types. - Session 5. Technology : diffusion properties and non equilibrium states. - Fundamentals of diffusion of water and rate of approach of equilibrium aw. - Diffusivity of sorbic acid in food gels at high and intermediate water activities. - Aroma diffusion : the influence of water activity and of molecular weight of the other solutes. - Choice of packages for foods with specific consideration of water activity. - The role of water in the rheology of hygroscopic food powders. - Session 6. Technology : humectants and new intermediate moisture foods (IMF). - A pragmatic approach to the development of new intermediate moisture foods. - Water binding of humectants. - Novel intermediate moisture meat products. - Extrusion cooking for cereal-based intermediate moisture products. - Polyglycerols and polyglycerol esters as potential water activity reducing agents. Chemistry and sensory analysis. - Session 7. Freezing and low temperature phenomena. - Complex aqueous systems at subzero temperatures. - The freezing of biological cells in aqueous solutions containing a polymeric cryo-protectant. - Freezing in polymer - water systems and properties of water. - Freeze-texturing and other aspects of the effects of freezing on food quality. - Computed instrumental analysis of the behavior of water in foods during freezing and thawing. - Session 8. Commodities : properties of water and technology. - Water in fish : its effects on quality and processing. - The effect of water on the quality of meat and meat products : problems and research needs. - Water in dairy products related to quality, with special reference to cheese. - Confectionery and water activity: determination of aw by calculation. - Session 9. Moisture measurement and prediction. - Comparison of sensors for measurement of air humidity. - Standardization of isotherm measurements (COST-project 90 and 90 bis).