Adjusting pressure setting and processing time when modifying pressure canning recipe
When it comes to pressure canning, is there a "golden rule" or standard for modifying recipe pressure settings or processing times when you want to change the quantity of jars used?
For instance, I am interested in cooking and canning this Split Pea and Ham Soup recipe.
Unfortunately, the recipe only makes 2 quart jars. I have a Presto 23-quart canner that can fit more than 2, and so -- if possible -- I would like to scale the recipe up to cook enough soup for 4 or maybe 5 quart jars worth.
But if I stuff 4 or 5 quart jars into the canner, does the pressure setting for this recipe (10 PSI) or the cook time (90 minutes) change? If so, what's the general rule for figuring these types of modifications out?
Best Answer
No modifications are necessary.
The pressure of the canner entirely determines the temperature of the water around the jar, and you don’t start timing until the canner is at that temperature/pressure, so regardless of the scale you’re assured of processing for long enough. In a larger canner and/or a weaker stove the contents of the jars will end up being slightly more cooked because of the longer lag time before you start the timer, but there’s not much you can safely do about that, and for pea soup it will make literally zero difference.
Pictures about "Adjusting pressure setting and processing time when modifying pressure canning recipe"
Can you process canning too long?
The steam should not come out in spurts; it should be steady and vigorous. If you shut your canner too soon, the food often will not heat for long enough during processing and can spoil in storage even if the lid appears sealed.Can different size jars at same time?
Because different sizes of jars require different processing times (larger jars take longer for proper heat penetration), for food safety, you should always use the jar size listed in the recipe. Remember: "You can always safely go down and process at the same time, but you cannot go up in jar size," Piper says.How long do you pressure cook when canning?
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