MSU Extension Food Preservation

It is important to stay informed on the latest food preservation processes, because food preservation methods can change based on science. Research is important in finding what process works best to kill harmful bacteria when preserving quality. It is especially important to refresh your knowledge if you have not preserved food for a few years. 

So how do you know if you are using the right food preservation process?

• Use a water bath or atmospheric steam method for high-acid foods. Different types of food require different methods of canning. Acid plays an important role in safely preserving your food; ultimately it determines which canning process should be used to keep food safe. High-acid foods such as fruit, relishes, picked products and salsas can be processed in a hot water bath or an atmospheric steam canner, with varying lengths of time.
  
  To know the correct amount of processing time you must follow a tested recipe. The basics of the water bath canning method involves putting filled jars in a pan that is deep enough to hold a large amount of water, that measures one to two inches above the jars. With the atmospheric steam canner, follow the processing time as you would a water bath. The USDA provides tested recipes and specific length of time for each food item to be processed. The USDA website features a variety of information on canning, pickling, jams/jellies, fermenting, freezing, drying curing/smoking, and storing preserved foods.
  
  
• Use pressure canning for low-acid foods. Pressure canning is for food that is low in acid, including vegetables, meats, soups and stews. Pressure canning causes heat to reach the center of the jar for a certain length of time to kill any bacteria that may be present. This process takes a piece of equipment called a pressure canner.
  
  
• Figure out which pressure canner is right for you. There are two types of pressure canners. One is called a weighted gauge and indicates pressure by rocking, and the other has a dial gauge that displays the pressure. Both canners need your full attention when processing foods. Be aware there are many safety features on newer canners that help keep you safe. MSU Extension advises not to leave the pressure canner while you are processing. It is important to refer to the USDA’s food preservation guide for home canning to figure out the recommended pressure and time to process specific foods.
  
  
• Be prepared. It is important to follow directions and recipes provided by trusted sources like the USDA, So-Easy-To-Preserve, Michigan Fresh Fact Sheets, the USDA’s Complete Guide to Home Canning or the most current edition of the Ball Blue Book when preparing foods to be preserved. These methods and recipes have been tested to help ensure your food is preserved safely and reliably. This typically will mean checking jar rims for chips or cracks, properly preparing the produce and properly keeping hands and items clean during the process.

Michigan State University Extension also recommends taking a class, such as the Food Preservation Workshop provided by MSU Extension's team of food safety experts, to learn the science behind food preservation methods. MSU Extension provides a variety of food preservation programs for anyone that may have the desire to learn the process. To locate a class on various types of food preservation, look on the MSU Extension website or locate your local food safety educator.