Safety is of utmost importance when preserving food because improperly home-canned food can lead to foodborne illness. Bacteria, yeasts and molds can grow quickly on fresh fruits and vegetables. Oxygen and enzymes that can cause food to spoil are found all over and inside produce. Safe home-canning methods help prevent the growth of these harmful bacteria, yeast and molds; remove excess oxygen from the food; destroy spoilage enzymes; and allow for year-round enjoyment of the foods from your garden.
Despite what you might find on the Internet or social media, there are only two methods that are acceptable for home canning safe, quality products. They are the boiling-water-canner method and the pressure-canner method.
The method you use depends on the type of food you are preserving. Boiling-water canners can be used on foods that are naturally high in acid, like most fruits. Pressure canners must be used for all fresh vegetables, meat, and poultry. Both methods, when used properly, can prevent botulism, a deadly form of food poisoning associated with canned food.
Foods that are naturally high in acid or foods that have been acidified with lemon juice or vinegar, like pickles, salsa, and relishes, can be safely processed in a boiling-water canner. The acid prevents the growth of harmful bacteria in these foods.
However, vegetables, meats, and poultry do not contain enough acid to prevent bacterial growth. These foods require temperatures between 240 degrees Fahrenheit and 250 degrees Fahrenheit to prevent the growth of bacteria. A pressure canner is the only way to reach temperatures this high. Therefore, all vegetables and other low-acid foods must be processed in a pressure canner.
Be sure to use up-to-date equipment that's in proper working condition. It's never a good idea to purchase a pressure canner at a yard sale or flea market because replacement parts and manufacturer's instructions might not be available.
Pressure canners made after 1997 are designed with more safety features and weigh much less than older canners. Dial gauge pressure canners should have the gauge tested each year. Your local Extension office can do this.
It is also important to use only Mason-type canning jars and self-sealing, two-piece lids. Never reuse jars that once contained mayonnaise or other food products as they will crack and break during processing.
Always use research-based recipes to preserve foods. These recipes are available in Cooperative Extension Service home-canning publications, the Ball Blue Book Guide to Preserving, or the National Center for Home Food Preservation's website https://nchfp.uga.edu/. Follow each recipe exactly as written. Do not make additions or changes, unless options are provided in the recipe. Not following the recipe precisely or using a recipe that is not research-based, can result in sickness.
For more information on safe, food canning and research-based recipes, contact your Cooperative Extension Office.
Source: Annhall Norris, Extension Associate