My exhausting jam-a-thon. Totally worth it. This is Christmas in the bank.
It was a loooong weekend last week. A three-day weekend that felt like a week.
Every single pear in that blasted bushel (about 80 pears) made it into a jar.


So, first I gathered my equipment:
. . . with clean jars, lids and rings, too.
And then I got to work.
Last weekend, I conked out on writing more about the process at about the point when I got all the pears into the refrigerator with sugar and lemon juice so they could macerate overnight. Sunday was a blur after that.
You skim the surface of the jam when it is nearly done to get rid of the hard white foam that seems to stick together. It comes off easily (don’t worry about that first early foam when the jam first gets hot — it will calm down by itself–that’s mostly air). The foam that remains when the jam is almost done are impurities that will make your jam not jewel-clear. You want to get off as much of that foam is you can:
So how do you know the jam is done? I keep some spoons on a saucer in the freezer, and put some of the jam liquid on a cold spoon, and put it into the freezer for one or two minutes, until the mix feels neither cold nor warm when you touch the bottom of the spoon.
One test is the drip test, where the jam has just the right viscosity:
Another test is the wrinkle test, where you can push it into a shape that wrinkles in front of your finger, and only goes back into a puddle very slowly:
After you get to the right done-ness, you add any final flavors, put into hot jars, and then start canning:
How do you know when to start the canning time? You need the water to come back to a rolling boil. Then you start your timer.
Like this:
After the processing time (10 or 15 minutes for the four recipes I made), you carefully remove the jars from the boiling water, and put them on a folded dish towel (to prevent thermal shock and cushion the bumps — particularly important on granite, which is much colder than the jars). I use my jar lifter, cupping the bottom of the jar with a silicone pot holder, lifting them out one at a time and gently setting them on an old folded dish towel. (Don’t use your nice towels for this. Stains happen.)
And then you listen for the sweet sound of success. It sounds like this. Watch carefully, and you can see the dome lids sealing — especially in the lower right of the final clip. The dome gets sucked down by the vacuum in the jar:
Some liquid preserves, like these pear slices brined in sugar, wine and vinegar, will continue to boil until they seal — some brine will come out. That’s perfectly normal.

Don’t move the jars or disturb them for at least 12 hours. One hour after removing them from the canning pot, gently push down on the center of each dome lid to make sure the jars are sealed (no popping noise when you push down means the jar is sealed). Any jars that don’t seal, should go into the refrigerator and be consumed within 2 weeks. If you’re experienced in canning, you can re-process unsealed jars to seal. Not-sealing can be caused by a dirty or chipped rim, old lids with worn out seals, jars that are too full, or a bad recipe.
The next day, remove the rings and gently rinse and dry the filled jars to remove all traces of sugar. Clean up carefully, especially in the case of overflowing brine, to prevent sugar ants. You can wash the rings to use later. Alternately, you can put clean rings back on. However, storing the jars without rings makes it very clear if something goes wrong with the batch — in a bad batch, the lids may lose their seal owing to bacteria buildup inside the jar. Those jars should be discarded. Once you open the jam, you can never re-use the dome lid again (although it’s OK to use it for a refrigerator-storage lid with a clean ring while you consume the jam). To be sure that used dome lids don’t make it back into your collection, open them with a pointy can opener that will make a dent in the lid. Also, never use a dome lid you’ve had for over a year. Buy fresh new ones each season. The red rubber ring will only form an effective seal if it is pliable and fresh.
Store your bounty in a cool dark place.