Canning is a method of preserving food. Put simply, the objective if canning is to put serialized food into a sterilized airtight container. In accomplishing this, canned food can last for up to 30 years. However, the typical shelf life of canned food is usually around 1 to 5 years.
In 1974, samples of canned food from the wreck of the Bertrand, a steamboat that sank in the Missouri River in 1865, were tested by the National Food Processors Association. Although appearance, smell and vitamin content had deteriorated, there was no trace of microbial growth and the 109 year-old food was determined to be still safe to eat.
Canning food was first used on a large scale by the French military. The reason for this was that at the time the military depended on horses and carts. This meant that shipping food was a long process. As such, fresh fruits and vegetables would often go bad long before reaching their intended destination. In many conflicts solders were more likely to die from malnutrition, disease, and food poisoning, than they were to die from enemy fire.
In 1795 the French military decided to remedy this problem by offered a cash prize of 12,000 francs for a new method of preserving food. A fellow by the name of Nicolas Appert suggested canning. The canning process was first proven to work in tests conducted by the French navy in 1806. Nicolas Appert, was later awarded the prize in 1810.
There are many different methods for canning. However, the most popular method is to boil the food under high pressure before putting them into a sterilized Mason jar. I am personally a big fan of salt. As such, I will often put a dash of salt in with my canned goods. Salt and sugar can make for an inhospitable environment for microbes.
Boiling water can kill most bacteria and microbes. However, some bacteria such as the bacteria that cause botulism can survive boiling water. As such, you may find it advantageous to invest in a pressure cooker.
The following is a simple guide to canning:
Step 1: The first thing you need to do is to collect your supplies. You will need food to be canned, Mason jars with lids, a pressure cooker, and towels.
Step 2: The next step with be to either rinse or cook any of the foods you are going to can. You will also want to boil the lids and rings to your Mason jars. Remember that serialization is key. As such, you will want to make sure that all of the surfaces and utensils have been washed and cleaned.
Step 3: You will then want to put your food into the Mason jars and fill them with water. You may also choose to put a dash of salt in as well. You will then seal your jars and place them into your steam canner (pressure cooker). You will need to leave some space between each jar.