INTRODUCTION
Freezing by Contact with a Cooled Gas
It is known by many names, such as cabinet freezing, air-blast freezing, belt freezing, spiral freezing and tunnel freezing.
Cryogenic freezing
Liquefied gases directly contact the foods in cryogenic freezing [1].
Emerging technology
ISOCHORIC FREEZING
Why is it different from other methods
In a typical Isochoric process,
PRESERVATION OF GRAPE TOMATO BY ISOCHORIC FREEZING
IMPACT ON ENZYME
The isochoric method helps lessen food browning. When potatoes were kept at 5 °C under isochoric refrigeration as opposed to isobaric freezing, there were noticeable differences in their colour.
FOOD QUALITY IMPACT
A constant-volume preservation method in a closed rigid container can better retain the food’s quality. For instance, potatoes lose weight at the same temperature in an isobaric freezing system. In contrast, when stored in an isochoric refrigeration system (5 °C) system immersed in a 10% (w/w) sucrose solution, potatoes experience no weight loss.
IMPACT ON MICRO-ORGANISM
Escherichia coli was shown to suffer from membrane damage, changes in the size and form of the cell, protrusions, ruptured membranes, and the outflow of intracellular materials after being isochoric-cooled to 15 °C.
FUTURE PROSPECTS