WATER-HOLDING PROPERTIES OF MILK PROTEIN PRODUCTS - A REVIEW

Water-holding properties have been well recognized by food technologis ts among the diversity of functional properties attributed to milk pro tein products. In general, water-holding is accomplished by a complexi ty of interactions between water and milk proteins. Besides the term w ater-holding, synonyms such as water retention, imbibing and hydration have been used to describe this phenomenon. This paper provides a cle arer understanding of this parameter by considering some fundamentals of both the molecular structure of milk proteins and the physical inte rrelationships between water and milk protein powder particles. Differ ences in water-holding properties of milk protein products are frequen tly observed and may be due to the nature of the protein and to techno logical influences. Methods measuring water absorption and methods tha t measure water retention are applied for the examination of water-hol ding. By following this distinction, the principles of various methods (e.g., the Baumann method, the absorption capacity test, Farinographi c procedures, net tests, filtration tests, modern instrumental techniq ues) are reviewed.