One such novel method is high-pressure freezing, which
results in instantaneous and homogenous ice crystal formation
throughout the product due to the high supercooling effect achieved
on pressure release. The result of the increased pressure causes a shift
in the type of ice crystals that are formed from type I (lower density
than liquid water) to type IV ice crystals. Type IV ice crystals are
smaller and denser than water and do not cause the product to
swell by 9–13%, the normal expansion that occurs with type I crystals.
The theory is that, with type IV ice crystals, there is less mechanical
damage to the cell structures, which results in a superior quality
product. The drawback of this method is the capital layout and the
product size limitation. Currently only products that are able to fit
into the product chamber (0.15 ml to 3000 ml) can be frozen in this
manner.