Yep, sorry. You need to do what the recipe calls for. Going smaller isn't usually a problem, but going larger is. You must use a lot of jam!

The traditional standard is to add 5 minutes to the processing time for pints. I'm speaking of regular full-sugar jams and jellies. I see several updated online Extension documents that still give that information, so it doesn't appear that has changed.

With a full-sugar preserve it really isn't an issue as far as safety is concerned. What you do want is full heat-penetration with more volume and the additional 5 minutes should achieve that.

I was interested in your comment and checked the BBB. I notice several preserves have been increased from 10 minutes to 15 minutes. I can only guess they're applying that to denser preserves; if there were an acidity issue they wouldn't be canning it by water bath in the first place.

Anyway, 20 minutes for pints should be fine.

Carol

Thank you! If I'm at an altitude of 1300 feet, I need to add an additional 5 minutes as well, right?

So, if the recipe calls for 15 minutes for half pints (as the blueberry lime jam does), I should add 5 minutes for altitude and five minutes for pints for a total of 20 minutes, right?

Thanks again! So helpful!

Yes, add more time. The main reason for using half pints is for the gel. You can get a weaker gel in pint jars due to the longer processing times. I don't see a safety issue at all in pints in this case. Normally it is a no no for safety reasons to use a larger jar. In this case I feel it is due to the gel issue.

I agree with Linda Lou. It isn't safety, it is quality.

We are at 950 feet and jell is not nearly as good with pints as with half pints. If you want the best results using pints then use a recipe that is designed for pints - and there are many of them - as they usually call for a different fruit to pectin ratio.

JMO

Dave

I've never had a problem with the gel in pints, even with a traditional jelly. We always canned in pints when I was growing up. There were too many of us for half-pints.

I don't have experience with the blueberry-lime. But since it contains commercial pectin, I'd say the odds of the gel breaking are pretty slim, even with the additional altitude issue.

All you can do is give it a try and see how it works for you. Some of these things individual canners work out through trial-and-error.

Carol

Thanks all!