Canning is a method used to preserve fresh food in jars using high temperatures to kill microorganisms and inactivating enzymes that could cause food to spoil. The heating process pushes air from the jars, creating a vacuum seal as jars cool. Without air, the bacteria, yeasts, and mold will not grow and food won’t spoil. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.