Canning of
foods first occurred in the 18th century but in jars! Due
to the demands of long sea voyages, armies being away from
home for long periods and the increasing needs of urban populations,
effective means of food preservation were required. At the
time, methods of preservation included drying, smoking, pickling
and salting of foods, but were inadequate for preserving
foods for a long period of time. Demand for canned food skyrocketed
during World War I, as military commanders sought vast quantities
of cheap, high-calorie food to feed their millions of soldiers
Canning
is a method of preserving food in air-tight vacuum-sealed
containers and heat processing sufficiently to enable storing
the food at normal-home temperatures. Canning is one of
the safest ways to preserve foods. To retain peak quality,
the shelf life of canned food is at least two years, and
the vitamin level in canned food remains stable during
the shelf life as long as the container is not damaged
in any way. Commercially canned food is very safe, actually
much safer than the home-canned kind and has a shelf life
of a good two years, often much more.
Canning has no effect
on proteins, carbohydrates and fats. If you take can meat,
for example, it will have the same
amount of protein and fat after canning as it had before.
In general, canning does not seem to affect the nutritional
values of food very much. From that point of view, you
don’t have to feel sorry about turning to a can for
a quick and convenient meal. Your fresh vegetables can
lose more vitamins by lying in storage rack for a week.
Canning is a useful way to preserve vitamins, as concentrations
of some vitamins can decrease by 50% within the first 7
days after harvest when stored at ambient temperatures.
Tinned
food only needs to be warmed through before serving because
it has already been cooked in the can. By keeping
the cooking juices, canned foods lose remarkably little
of their nutritional value. Canned poultry and fish, both
protein foods, are comparable to their fresh-cooked counterparts
in nutritional value. Protein is not lost during the canning
process. And some varieties of canned fish tend to have
higher calcium levels than their freshly cooked counterparts.
Many
canned fruits and vegetables are high in vitamin A; canned
products have comparable levels of vitamin A
to their fresh or frozen counterparts. Tinned food retains
vitamin C for up to two years because the can is completely
sealed and the food inside is cooked and stored in a vacuum.
Fresh fruit and vegetables may start with more vitamins,
but crops that go directly from field to processor often
retain vitamins better than those that travel across the
country and sit for days in produce bins or at home in
refrigerators. Canned pineapple, asparagus and grapefruits
are significant sources of vitamin C.
There are an enormous
variety of canned foods, which differ both in terms of
type of ingredients and method of processing.
In the end, it can be clearly stated that it’s better
to go for canned food rather than bad food. |
