The frozen state in mammalian muscle

In common with the majority of colloidal systems, mammalian muscle when frozen undergoes serious structural change, part of the water previously held within the muscle fibres being expelled on thawing as a synaeretic fluid. The trend of recent work on the freezing of tissues has been to minimise the factor of cold and to regard the equilibrium effects of freezing as being produced by a certain measure of desiccation. In the case of living muscle an exact correlation between freezing and drying has been definitely established (Moran, 1929; Smith, 1929; Smith and Moran, 1930). One of the difficulties, however, in extending the concept to mammalian muscle, post-mortem, is the lack of data as to the amounts of water actually present as ice at different freezing temperatures. The present paper describes the results of an attempt to supply this need for three examples of mammalian muscle, namely, beef, mutton and pork.