Canning

Canning

Making salmon cans

Canning is a method of preserving food in which the food contents are processed and sealed in an airtight container. Canning provides a shelf life typically ranging from one to five years, although under specific circumstances, it can be much longer.

History

Early canning methods

The process of canning was first developed in the late 18th century as a way to preserve food for the military. The French government offered a cash prize for a new method of preserving food, which was won by Nicolas Appert, who developed a method of sealing food in glass jars. This method was later adapted to use tin cans, which were more durable and easier to transport.

Process

Canned foods

The canning process involves placing foods in jars or cans and heating them to a temperature that destroys microorganisms and inactivates enzymes. This heating and subsequent cooling forms a vacuum seal. The vacuum seal prevents other microorganisms from recontaminating the food within the jar or can.

Steps

1. Preparation: The food is prepared by cleaning, peeling, chopping, or cooking as necessary. 2. Filling: The prepared food is placed into jars or cans. 3. Sealing: The containers are sealed with lids or caps. 4. Processing: The sealed containers are heated to a specific temperature for a set period of time. 5. Cooling: The containers are cooled, creating a vacuum seal.

Types of Canning

Cannery worker filling tuna cans

There are two main types of canning: water bath canning and pressure canning.

Water Bath Canning

This method is used for high-acid foods such as fruits, pickles, and tomatoes. The jars are submerged in boiling water for a specified time.

Pressure Canning

This method is used for low-acid foods such as vegetables, meats, and seafood. The jars are placed in a pressure canner, which allows the temperature to rise above boiling.

Industrial Canning

Artashat Cannery

Industrial canning is a large-scale operation that involves automated machinery to fill, seal, and process cans. This method is used to produce canned goods for mass distribution.

Home Canning

Home canning is a popular method for preserving food at home. It allows individuals to preserve seasonal produce and create homemade jams, jellies, and pickles.

Safety

Canning is a safe method of food preservation if done correctly. It is important to follow proper canning procedures to prevent the growth of Clostridium botulinum, which can cause botulism, a potentially fatal illness.

Related Pages

• Food preservation
• Pickling
• Fermentation
• Clostridium botulinum

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