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It’s strawberry season – the perfect time to pick them fresh from the field and make strawberry jam that tastes like summer in a jar. But don’t let your vision turn into a nightmare. Having a great recipe and the right equipment is critical. And so is knowing what not to do.A great recipe and the right equipment is critical. So is knowing what NOT to do. Click To Tweet
A Word About Strawberry Picking
Only pick the berries that are fully red because strawberries don’t continue to ripen after picking. Those white/pink berries will stay white/pink – and flavorless. Also, unless you’re planning to make jam that evening, don’t pick berries in the heat of the day. Pick them in the cool morning or evening or they’ll start to soften. And by soften, I mean turn to mush within 24 hours.
The best way to store the strawberries when you get them home is in a shallow container in the fridge.
Assemble & Prepare Materials
In addition to your perfectly ripe strawberries, you’ll need lemons (or bottled lemon juice) and pectin. You’ll also need jelly jars with lids and rings and a large pot suitable for a canning bath. It’s also advisable to use a wide-mouth canning funnel to get the jelly into the jars without making a mess.
This big beautiful pot is brand-spankin’ new and I couldn’t use it. Once I got it home, I noticed a warning on the instruction sheet not to use it on a ceramic-topped stove – which is what I have. But it didn’t say why. Turns out the ridges on the bottom of the pot don’t allow the sensors of ceramic stoves to keep the element on long enough to make the water in a pot that size boil. Short answer: it’s not safe because it can’t ensure safe-to-eat jam.
So I used another, smaller, flat-bottomed pot I had. Never roll the dice when it comes to potential food poisoning. Big Beauty is going back to the store so someone with a gas stove can buy her.
Step 1: Place jelly jars in a large pot of water and bring to a rolling boil to kill any bacteria. Turn off the burner and let pot simmer while you prepare the jam.
Now You’re Cooking
Step 2: In an 8-quart saucepan, mix 3 and 3/4 cups of washed, capped, and sliced strawberries, 1/4 cup of lemon juice, and 7 cups of granulated sugar. Bring the mixture to a full rolling boil, mashing berries with a potato masher. Or, if you like a smoother consistency like I do, use an immersion blender.
Add the pectin and return mixture to a hard boil for one more minute. Skim the foam off with a large spoon.
Step 3: Put the lids and rings into the pot with the boiled jars. The hot water will activate the seals on the lids as well as sterilize them. But if you put them in the water while it was boiling, you’d make the seals useless. Leave the lids and rings in the water but remove the emptied jars (carefully, they’re hot!) to a wire rack on your counter.
Step 4: Fill the jars with the hot jam leaving just 1/4 inch of headroom. Wipe the rims of the jars with a wet paper towel to clean – do not neglect to do this or you could compromise the seal.
Step 5: Take the seals out of the hot water, one by one, and center each on a filled jar. Secure by applying a ring snuggly.
Step 6: Return filled jars to the large pot, on the stove, filled with hot water. Make sure water level covers the jars and bring to a boil. Boil for 10 minutes. You should see a few little air bubbles seeping from the lids as in this picture.
Step 7: Remove jars from water bath and return to wire cooling rack. Over the next hour or two, as the jars cool, you’ll hear the lids give a little “pop” indicating the seal has set.
Step 8: Cool jars for 24 hours and check lids. The lids should not flex up and down at all when you press on the center of them. Jam should last as long as the lids have no flex to them.
Now You’re Jammin’
Here’s what your finished product looks like.
Critical “What Not To Do” Tips
Learn from my previous mistakes and don’t do these:
- Don’t reduce the sugar or use a sugar substitute. If you do, your jam won’t gel and you’ll have canned strawberry ice-cream topping instead. If you want to lower the sugar content, make sure you buy the pectin made especially for low or no-sugar recipes.
- Don’t double-batch the recipe. For some reason, this also negatively affects gelling. Make 2 batches.
- Don’t freak out if your jam isn’t set right away. It can take up to 2 weeks to fully gel. That’s right – 2 weeks.
Step 9: Enjoy!