Microbial growth at reduced water activities: studies of a w prediction in solutions of compatible solutes

Studies were made of the prediction of intracellular water activity ( a w ) of microorganisms grown at reduced a w . These included the determination and prediction of a w of potassium L‐glutamate solutions and the prediction of a w in mixed solutions of various compatible solutes and macromolecules. Compatible solutes studied were L‐proline, glycerol, potassium chloride and D‐arabitol. The results indicate that a w predictions of such mixtures may be done with acceptable accuracy by neglecting solute‐solute interactions.