Canning is cool again, but who's to say it ever went out of style? After all, the delicious tastes of garden-grown veggies and jammy preserves are always satisfying. If you're getting into the habit of canning your home-grown produce, consider the following tips:

What is canning?

Canning, as the name implies, is the process of preserving food in cans. At the grocery store, you can find all sorts of fruits and vegetables preserved in cans. At home, you're not likely to use actual cans, but rather glass jars with sealed lids.

Surprisingly, we have Napoleon to thank for canning. In 1800, the French emperor offered a cash reward to anyone who could develop a method of preserving food for soldiers on the march. Confectioner Nicholas Appert developed a special jar that could be sealed when heated, won the prize money, and gave the world a life-saving invention.

Today, many households across Canada preserve home-grown produce to enjoy the delicious flavors all year round and save on grocery costs. Others preserve fresh vegetables from their local farmers market.

What is the most effective canning method?

There are two modern methods of canning foods: water bath canning and pressure canning. The first method uses boiling water to heat jarred food, creating a seal; the second requires a special piece of equipment called a pressure canner to rapidly seal jars at a high temperature.

"The water bath method is more popular than pressure canning."

The water bath method is ideal for high-acid foods such as fruits, tomatoes and pickles. Because this method keeps the produce submerged in hot water for a long time, it destroys any imperfections like mold or yeast.

The pressure canning method is best for low-acid produce and foods that are especially prone to spoilage. This method is the only way to effectively can meats, poultry or seafood. In the pressure canner, a high temperature eliminates bacteria.

It should be noted that there are other canning methods that use an oven or kettle to produce heat. However, these methods are not able to achieve the same pressure levels as the water bath and canner methods, and may cause faulty seals.

The water bath method

To begin, boil water to 82 degrees Celsius. It's important to check each jar for nicks or scratches around the seal. Even a small flaw can cause the seal to fail. Canning jar lids come in two pieces - a ring and a top. The ring should fit snugly on the jar. Wash all jar components in warm water using a gentle soap. Rinse thoroughly, then place them in the boiling water.

The easiest and safest way to move jars in and out of the water is to use a special jar rack. Always use a towel or oven mitt to hold onto the glass or metal pieces that might have come in contact with the boiling water.

To prepare your recipe, remove one jar from the water at a time. Fill the jar with your ingredients, remembering to leave some space between the food and the jar lid. Your recipe will tell you how much room to leave. The wrong amount of air for the recipe could cause the seal to fail. To remove air bubbles that form along the sides of the jar, use a wooden skewer or rubber spatula. By paying close attention to air bubbles at this stage, you'll increase the chance that each jar will seals successfully.

Before placing the lid on the jar, wipe down the rim with a clean cloth. The threads should be completely free of residue. Place the top of the lid firmly on the jar, then tightly screw on the ring. Finally, return the jar to the boiling water. The jar should be covered by at least five centimeters of water. Place a lid on the pot. Every recipe has a unique processing time. After the jars have been in the water for the appropriate amount of time, turn off the heat, remove the pot lid, and let sit for five minutes before removing the jars.

As you remove them from the water, place each jar on a towel. Let sit for 24 hours. To test the seal, unscrew the lid ring and attempt to lift the top with your fingers. The seal should be strong enough to resist the effort. If not, refrigerate the jar and consume, or toss. Canned goods can remain fresh for up to 18 months when stored in a dark, cool and dry environment. 

Canning preserves garden fresh flavors for months.Canning preserves garden fresh flavors for months.

The pressure canning method

Boil water in your pressure canner. As with the previous method, inspect and wash each jar and lid, then place in water boiling at 82 degrees celsius. Removing jars one at a time, fill each with your desired recipe and remove air bubbles. Wipe the lip of the jar to completely remove any residue, then firmly attach the lid, and place the jar in the pressure canner.

With all the jars in the canner, lock the lid and adjust the heat level to the high setting. You canner has a steam vent. Let steam escape from the vent for 10 minutes, then close off the vent, careful not to let the steam touch your skin.

Your recipe will tell you how long to leave the jars in the canner. When the time is up, turn off the heat and let the canner sit for another 10 minutes. Open the lid, then let sit for 10 minutes more. Waiting the proper amount of time will allow the food to seal properly and reduces the risk of steam burns.

Place each jar on a towel and let sit for 24 hours. Repeat the tests from the previous method to test each seal.

Canning is fun and accessible. Plus, it can support a healthy lifestyle. Give it a try with your friends and family to preserve this season's flavors for months to come.