Studies of solution processes in hydrated starch and agar at low moisture levels using wide‐line nuclear magnetic resonance

Summary Experiments are described in which the proton magnetic resonance absorption of samples of hydrated starch and agar have been measured in the presence and in the absence of added test solutes containing different proportions of readily‐exchangeable hydrogen atoms in their molecules. The effect of these additions is described in otherwise untreated systems and in systems in which the hydrogen in the hydrated absorbent had been largely replaced by deuterium. In both cases, the size of the resonance absorption signal is unaffected by the additive at low levels of hydration of the colloid absorbent, but above a particular moisture content for each combination of absorbent and solute, the addition of the latter causes an incremental increase in signal. Evidence is presented that this increase is due to mobilization of the solute itself in the water present and does not arise from any influence of the additive on the condition of the water.