The hydration or combined water of gelatin

Abstract

In a previous paper it was shown that when gels of gelatin are so frozen that the ice and the gel phases are separated by a plane surface so that they are at the same temperature and pressure, there is a clear cut separation into ice and more concentrated gel and the concentration of the latter is determined by the temperature; there is in short a completely reversible phase equilibrium between ice and gelatin gel. This earlier work has since been extended by experiments over a wider range of temperatures and with gels containing varying amounts of non-electrolytes and neutral salts. The present paper is an attempt to define the state of the water in gelatin gels from an analysis of these data.