Physical Chemistry of Foods

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Globular proteins can denature at low temperature, for the most part
because of decreased hydrophobic interaction; see Figure 7.5. The
denaturation is generally reversible, but enzymes are inactive in the
denatured state.
Most microorganisms cannot grow at temperatures below zero,
although their fermentation activity may slowly proceed at some
degrees below zero.

Freeze-Concentration. Freeze-concentration has been discussed.
Some examples of the proportion of water frozen are in Figure 16.10. By
and large, the smaller the initial freezing point depression of the product, the
higher the proportion of water that can freeze, although it also depends on
the water content at which a glass transition is reached, which depends in


FIGURE16.10 Examples of the proportion of water frozen as a function of
temperature in some foods.

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