Q: I am looking to make blueberry jam to give as a wedding favor when I get married next June. I want to can in small 2-ounce jars, but I am having trouble finding information on how to process them and how long the jam's shelf life will be in these mini jars. Any help would be greatly appreciated!
Sent by Sara
Editor: Sara, congratulations on your upcoming wedding! While I haven't canned in jars quite so tiny, for my own wedding I canned jam in small 4-ounce jars and processed them with the help of a Master Preserver friend, using the same hot water bath method as you would with a larger jar.
Hopefully some of our readers have had some experience canning in mini jars. In the meantime, here are some helpful hints for small-batch canning from Marisa McClellan of Food in Jars:
• Why Small Batch Canning Is Awesome: And What You Need To Get Started
Readers, do you have any advice or expertise for canning in 2-ounce jars?
Related: Small Batch Recipe: Strawberry Thyme Jam
(Image: Marisa McClellan)
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I have no idea, but this is such a nice idea! A wedding favor I would actually use!
I would use the processing time for half pints or the smallest size listed. But please make sure that there's enough acidity in your jam recipe because no matter how long you process it, not enough acid and it becomes like Russian Roulette.
The processing time is usually around 10 minutes for jam ... I would probably stick with that, despite the smaller size. I don't think it'll harm the jam, and better safe than sorry! Shelf life is usually at least a year. Good luck and congrats!
I would first make sure your jars are actually designed for boiling water bath canning; otherwise, they might not be safe to use. For processing time (and overall safety), you can follow one of these recipes.
Processing time is the same for jars in sizes 2, 4, 8, 12 and 16 ounces (typically ten minutes). It increases for larger jars. This is because 10 minutes is the baseline for sterilization.
the usda guide to pickling and canning might help. just google it. it's worth noting that the use of presterilized jars while not necessary, cuts down on canning time and makes for a better gel if you are using pectin. its only 5 mins in the water bath for pint jars if you sterilize them 1st vs 10 if you dont.
In any case, if you purchase your jars by the case via Ball or Kerr (here's their website http://www.freshpreserving.com/home.aspx) normally it comes with a detailed guide to canning.
As a rule, the [small] size of the jar is not relevant. It's the *process* that's important. The exception would be very large canning jars which are rarely used. Congrats..
We canned about 40 different items (for a total of 280 favors) for our wedding favors (including jam). We used small 2 & 4 oz jars and canned items like pickled beets and asparagus in pint jars. Processing time is the same. We also canned about 10% more than we anticipated needing and randomly selected samples at different intervals (we canned in our spare time for >1 year). I just finished one of the extra blueberry jams, and it was perfection. We had GREAT feedback from family and friends who attended, and it let us showcase some of our amazing Northwest foods and our love for food and cooking. Congratulations, and good luck!
Thank you everyone! The tiny jars are not 2 pieces, so the USDA does not have information on it and does not recommend them. That said, I see them used all over, so I'm sure it's possible!
Try the oven!! I sterilize my jars for 30 mins at 250 degrees and then fill and put them back in to process for 10-15 mins. I find it so much easier than the whole boiling water thing. I can process lots of jars at once too- I put them on a sturdy half-sheet pan. This works with one and two piece lids and if you have an oven thermometer is totally fool proof.