Food Preservation: Canning

Hopefully we are past the final frost and all the rain and warmth will lead to an abundance in the garden this year. So how can we maximize our gardens? Food Preservation in the form of freezing, canning, and drying. This is article 2 of 4, where we will discuss canning. Freezing is a cheap, easy way to preserve foods where bacteria growth is stopped and items last longer. However, preserving foods by freezing is limited by freezer space. So how else can we stop bacteria growth without a freezer? Canning!

Canning is an excellent method of food preservation, but must be done correctly in order to be safe. There are 2 types of canning: water-bath canning and pressure canning. Both types of canning are great, but the method you will use depends on what foods you want to preserve. So, if you are new to canning, step 1 is to decide which foods you want to make and what the correct canning method is.

So which method to use? Well, it all comes down the acidity of the food. Acidic foods such as fruit, jams and jellies are canned in a water-bath canner. The acid in the food is one of the contributing factors to slow bacteria growth, but sugar/salt content is equally important. To ensure safety, most tested recipes will add additional acidity to the fruits or vegetables to ensure the product is acidic enough for water-bath canning. Foods that are further acidified in this manner, such as pickles and salsa, can be preserved using a water-bath canner as well. Low-acid foods such as vegetables, meat and seafood must be canned in a pressure canner to prevent botulism.

Canning is an art, as well as a science. Following a few guidelines, and working with the Extension office, can help you to be successful. Be sure that if you are using a pressure canner, that pressure dial gauges are checked each year. Checking gaskets and parts to ensure they are in working order is also important. Be sure to follow a tested recipe by USDA or Extension, to ensure that it is safe. By testing a recipe in a controlled laboratory setting, we are able to measure the internal temperature of a recipe in a specific size jar and be sure that it gets hot enough to kill bacteria. Using a tested recipe is such an important part. Like most things, new information is discovered and new technology is tested, so canning books published before 1994 may be out of date. After choosing a recipe, you want to be sure to wash all produce thoroughly in clean water to remove dirt and bacteria. Next, check your recipe for the proper headspace when filling jars. Too much headspace makes it difficult to remove air and produce a good vacuum seal, while too little headspace and the lids may not seal properly. Last, label your jars with the name of the food and the date. Home canned foods have the best quality when eaten within a year.

Because canning is such a great way to preserve foods, it is making a comeback and many people are canning at home. Using reliable information and tested practices will ensure that your home canning is safe and the quality of the product is good. Two reliable sources of canning information on the Internet are: nchfp.uga.edu and ag.tennessee.edu/fcs/Pages/Food/FoodPreservation.aspx. For answers to your home canning questions or to schedule an appointment to have your pressure gauge tested, contact your local extension agent, Alyshia Victoria, by phone 865-992-8038 or email aphill34@utk.edu. Happy canning!