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Physical-chemical basis of injury from intracellular freezing in yeast

1967; Elsevier BV; Volume: 3; Issue: 4 Linguagem: Inglês

10.1016/s0011-2240(67)80025-7

1090-2392

P. Mazur,

Food composition and properties

The death of cells of Saccharomyces cerevisiae cooled at rates above I-lOoC/min is correlated with the formation of ice crystals within the cells.This view is based on the following evidence:(1) The cooling rates that produce death coincide with those that cause intracellular water to become supercooled; (2) The volume of rapidly cooled cells is much larger than it would be if they contained no ice; (3) Alternative hypotheses do not account for the observed data.Cells that are killed under conditions yielding intracellular ice show extensive permeability damage immediately after thawing.Evidence is presented to support the view that intracellular freezing is a cause of death and not a consequence of death from some other cause.This view is based chiefly on the observation that survival is proportional to warming velocity.Two explanations for the lethal action of intracellular freezing are discussed.One is that injury is due to the removal of water by intracellular ice; the other is that injury is associated with the tendency of ice crystals to attain a minimum surface energy (i.e., a maximum radius of curvature).The evidence with yeast favors the latter.