One way to preserve food is to heat it up and put it in sealed jars. Why does this method work?

Answer 1

Check out this page.. says a lot about canning food and preservation!

http://en.wikipedia.org/wiki/Canning_%28food%29

;o)

Answer 2

When you can or bottle food it has to reach a point above boiling. This kills all the harmful bacteria in the food and the lids (which are either sealed by machine or have a rubber ring inside) are sealed. These seals are air-tight; this keeps all other things our of the bottle or can until opened. It also creates a vacuum which is why some jars are difficult to open.

Answer 3

i can work out having a 2 or 3 week supply yet 2 years??? i'm notably useful the food would loose various its nutritional value even despite if it rather is sealed in a bag. they do no longer placed that many preservatives in the canine food. Canned would final longer yet 2 years properly worth??? you does no longer p.c. to feed a canine in basic terms canned food for that long. And for a manner some years do you propose on protecting this?

Answer 4

Heating kills any bacteria and viruses in the food ("pasteurization" after famous French pioneer of microbiology, Louis Pasteur)
The warmed food also expands in size, so when it cools in a sealed jar it shrinks and thereby creates a vacuum lock.

Answer 5

Heating it kills the bacteria while putting it in an airtight sealed jar keeps the bacteria out until it is opened.