Microcentrifuge-Based Method for Measuring Water-Holding of Protein Gels

A method developed to measure water-holding properties of protein gels provides high precision and expanded analysis. A cylindrical gel sample was placed in an inner cell (which at its base contained a filter membrane) of a commercial microfiltration unit. The unit was then spun in a horizontal rotor microcentrifuge. Rates of water loss and degree of compression were determined. The rate of water loss could be modeled as the summation of two exponential decay functions. Degree of compression correlated with held-water. Gel rehydration ability and microstructure were used to study effects of centrifugal compression on gel structure.