Venting

Asked July 29, 2018, 7:27 PM EDT

I forgot To vent my presto canner before canning green beans , i left The weights on and timed 25 min after the jiggle began , should i reprocess ? And If so how do i do That ?

Martin County Kentucky family and consumer sciences pressure canning martin county kentucky

1 Response

Hello!

Forgetting to vent the pressure canner can result in green beans that are not safe to eat. If it has been less than 24 hours, you can safely reprocess. Remove the rings and lids and replace with new lids. Follow the instructions to vent the canner, bring to pressure, and process for the full recommended time. See more information below from the National Center for Home Food Preservation to understand why this is important.


Serious errors in processes obtained in pressure canners can occur if any of the following conditions exist:




  • Air is trapped in the closed canner during the process. Air trapped in a pressure canner lowers the temperature obtained for a given pressure (for example, 10 or 15 pounds pressure) and results in underprocessing. To be safe, USDA recommends that all pressure canners must be vented 10 minutes before they are pressurized.

    To vent a canner, leave the vent pipe (steam vent) uncovered (or manually open the petcock on some older models) after you fill the canner and lock the canner lid in place. Heat the canner on high until the water boils and generates steam that can be seen escaping through the open vent pipe or petcock. When a visible funnel-shape of steam is continuously escaping the canner, set a timer for 10 minutes. After 10 minutes of continuous steam, you can close the petcock or place the counterweight or weighted gauge over the vent pipe to begin pressurizing the canner.

Replace the lid with a new, properly prepared lid. Repeat the canning process, using the same processing time for this second process. Another option is to refrigerate the jars and eat the beans within a week, or to freeze the green beans for longer term storage. If more than 24 hours had passed, then we would recommend that you discard the beans.

There are cases of botulism from under-processed home-canned green beans and other vegetables. These two short reports document that this is hazard to be taken seriously.
http://nchfp.uga.edu/publications/Botulism_NCSU_greenbeans.pdf
http://nchfp.uga.edu/publications/botulism_NCSU_beets.pdf

August 2014
Kasey Christian, National Center for Home Food Preservation