Hey y’all,
I tried pressure canning for the first time last night with some blackberry jam. I opened the canner this morning and all the seals seem good but a lot of them have bubbles in the jam. Are these safe to eat/store without refrigeration?
by kraa_kraa
7 Comments
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As is normal here what recipe did you use? Now that’s out of the way, from my experience jams are commonly done by the water bathing process so this is unusual, to me.
A safe recipe, followed, is key to having a safe product to eat & share.
A wonderful recipe is found here, from one of our safe and tested websites, Ball’s Healthy Canning :
https://www.healthycanning.com/blackberry-jam-with-pomona-pectin
and another safe website Bernardin:
https://www.bernardin.ca/recipes/en/light-blackberry-jam-no-sugar-needed-pectin.htm
Pressure canning is a wonderful process that permits us to can vegetables, meats, & fishes all because of the higher temperatures. If I may be so bold, here is some reading for you because you are starting your canning journey:
https://www.healthycanning.com/pressure-canning-step-by-step/
Cheers!
edit – spelling
Bubbles aren’t unusual as pressure canned contents cool. The jar had been at pressure when the lid sealed, now it’s at a vacuum. That can create bubbles. In watery contents, you’ll see the bubbles rise and pop as the jar cools. In thicker contents, smaller bubbles don’t rise, so they stay trapped as things gel. Bubbles aren’t a safety issue by themselves.
But why pressure can jam? In general, most recipes call for water bath canning for jams and jellies because (a) they don’t need the higher temperature for safety and (b) pressure canning gets hot enough to caramelize fructose, so it won’t taste like fresh fruit.
There are recipes that use pressure caramelization intentionally for flavor, but I don’t think I’ve seen a published jam recipe that does, only privately tested/proprietary ones.
Jams and jellies never need to be pressure canned. I prepare them in 1/2 pint jars and it only takes 10 minutes in the water bath to process for safety. They are a high acid product…you use pressure canning for low acid things. The extreme high temperature would also affect the gelling properties of pectin.
Water bath and pressure canning are not (for the most part) interchangeable, although tomato products can be done with both.
Update: I tried it and it’s a little too sweet and acidic. I made 9 jars…
…what was this supposed to be?