Safe Summer Canning
Canning is a great way to preserve an abundant harvest for later. There are a few different methods for canning, such as Boiling and Pressure Canning. Regardless of the method, the goal is to alter the conditions as such to prevent the growth of unwanted microorganisms-bacteria, molds, and yeasts by inhibiting the interaction of food enzymes, oxygen exposure, and moisture loss.
The National Center for Home Food Preservation (NCHFP) is a trusted authority on all things related to canning, especially regarding safe home canning practices. In order to properly preserve canned fruits, vegetables, and meats, and to prevent the growth of harmful bacteria, such as Clostridium botulinum, there are some important guidelines that must be considered. Clostridium botulinum live as spores or vegetative cells which can produce deadly toxins within 3 to 4 days of growth in a low-acidic, moist, moderate temperature, low-oxygen environment. The USDA’s Complete Guide to Home Canning explains research-based guidelines for home canning, in order to prevent the growth of harmful bacteria in canned foods, such as Clostridium botulinum.
The most important step to home canning is choosing the right method based on the acidity of the food. For example, whether to use a pressure canner or boiling-water canner depends on the acidity of the food. All low-acid foods (pH value higher than 4.6), such as red meats and all fresh vegetables except for most tomatoes, should be sterilized at a temperature of 240° to 250°F, which can be easily done with a pressure canner operated at 10 to 15 PSIG for 20 to 100 minutes. Acidic foods (pH value of 4.6 or lower), such as most fruits, can be sterilized in boiling water for 5 to 58 minutes, depending on the specific fruit. Low-acidic foods require sterilization at a higher temperature in a pressure canner because they are not acidic enough to kill off dangerous bacteria like acidic foods can.
Finally, It is essential to choose and follow a published canning recipe, as the proportions of acidic liquid, canning temperature, and processing times are specific to each type of food, in order to safely prepare them for storage.
For further information on how to produce both safe and tasty canned fruits and vegetables, you can visit the NCHFP’s website.
https://nchfp.uga.edu/how/general.html
https://www.coshoctontribune.com/story/news/2021/08/08/dos-and-donts-canning/5511132001/
https://nifa.usda.gov/press-release/usdas-complete-guide-home-canning-available