Free water in hair keratin? a depolarization thermal‐current study

Abstract

Abstract In the keratin structure, the presence of water having the usual properties of “bulk water” has been discussed for many years. Results of experiments designed to study this question are conflicting and thus do not allow a precise idea of the state of water molecules in keratin at high hydration. A recent depolarization thermal‐current (DTC) study gave good evidence for the presence of a well‐defined DTC peak in the depolarization spectrum of ice. Initially, we verified the exact characteristics of this particular peak under our own experimental conditions. Subsequently, we looked for and found this ice peak in keratin samples. It appears when the water content is 19% or greater. The meaning of this result is discussed in relation to the other experimental results reported in the literature dealing with this question.