salts and other compounds that are only slightly soluble (such as
phosphate) may precipitate out, which will change the pH (Einen
et al. 2002) and ionic strength of the unfrozen matrix and cause
conformational changes in proteins. Ions in the concentrated
matrix will compete with the existing electrostatic bonds and
cause the breakdown of some of the electrostatic bonds (Dyer
and Dingle 1961, Shenouda 1980). Takahashi et al. (1993) found,
in their freeze denaturation study of carp myofibrils with KCl
or NaCl, that freeze denaturation above −13◦C is caused by the
concentrated salt solution. Effect of freeze-concentration in a
cellular structure was demonstrated in a phospholipid liposomal
model system (Siow et al. 2007).