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There were high losses in storage in bygone years - if grain
was not dry enough, it could be spoiled by mildew or fungus, there
were high losses to mice and birds, apples could only be stored
for a few months, potatoes and other roots could be stored under
heaps of earth for 6 months, cabbage could be pickled, jams could
be made, hams and fish could be smoked or salted, and people could
get through the winter until the first green shoots of spring
arrived, perhaps tightening their belts a little to get by.
Later, foods could be canned, or bottled, or dried.
Nowadays, it is a different story. Even if there were no imports,
one can find local apples, onions and potatoes everywhere that
have been stored for 9 months before being sold, still looking
perfect.
How is this done ? I think there are 3 main possibilities
- Now that air-conditioning equipment is easily available, some
crops can be kept for a long time at constant temperatures in
cool rooms, just above freezing, especially with good aeration
( apples or potatoes, would be spoiled by freezing)
- Many products are deep-frozen, either raw or after initial
cooking.
- A process of irradiation has also been introduced, where the
product is exposed to radiations from radioactive isotopes.
This results in products which are biologically dead, but which
look fine.
With imports as well, we can now buy Brussels Sprouts in April
and strawberries at Christmas !!
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