It really is all about the chemistry. Safe home food preservation boils down (ha ha) to the correct technique for the acidity level of the food.
For instance, foods with a high acidity level present an unfriendly environment to most pathogens, and these foods may be safely canned at the temperatures reached by a water bath canner.
However, low-acid foods provide a welcome mat to most pathogens. Because of the friendly conditions for bacterial growth, foods with a low acid level must be canned at a higher temperature to ensure that all the danger of food borne illness has been avoided.
Water boils at 212 degrees F — no higher. A temperature of 240-250 degrees F for 20 to 100 minutes must be reached to eliminate all the pathogens which can grow in low-acid foods.
The pressure canner to the rescue.
This handy device allows the home food preserver a great deal more flexibility as regards to the types of foods which may be canned. Although many foods qualify for pressure canning, the Master Food Preservers of El Dorado County recommend that you, “follow directions exactly. Never can vegetables or meats for which you do not have a research-tested processing time. Canning time is dependent upon many factors; the amount of starch, tightness of the packed food, microorganisms which contaminate and grow in that type of food, type and size of pieces packed in the container, and temperature at which the food is processed.”
Learn how to use a pressure canner properly at the free public education class offered by the MFPs on Saturday, Aug. 11, at the UCCE office. The class will be repeated on Tuesday, Aug. 14 at the Marshall Grange.
Both classes will be held from 10 a.m. to noon. MFP volunteers will demonstrate how to use a pressure canner and will be happy to answer any questions about pressure canning or home food preservation. Detailed written instructions on the use of pressure canners will be available.
Older pressure canners and some newer models as well, may not be calibrated correctly.
The Master Food Preservers offer a free pressure canner testing service. Call the office (number below) and leave a message and someone will return the call with more information about the service.
For questions about safe home food preservation or to schedule a speaker for organizations or clubs on the topics of food safety or food preservation call the Master Food Preservers at 530-621-5506.
For more information be sure to go to the Master Food Preserver Website at cecentralsierra.ucanr.org/Master_Food_Preservers/. Sign up to receive the new Master Food Preservers E-Newsletter at ucanr.org/mfpenews/.