There are a few failproof signs of fall for me. Catching a whiff of wild Concord grapes on a cool day in September is one of them.
The heady, slightly musky smell is a sure sign that the weather is well on its way to turning colder. (Do you have grapes growing out back in your yard? Then you know just the intoxicating fragrance I’m talking about.) I was delighted to find them when we were out and about this weekend. I grabbed a few boxes, and practically skipped home to make some jam.
Facts about Concord grapes
Concord grapes are the very same little purple wonders that give Welch’s grape juice its signature flavor.
Concord grapes come from (you guessed it) Concord, a now-sleepy little Massachusetts town that was a hotbed of activity during the Revolutionary war. Concord was home to writers and thinkers like Thoreau and Emerson. And it’s also not that far from where we live in Salem.
They were first planted by Ephraim Wales Bull in 1854. His grapes were hardy, and survived in Concord, where other European varieties did not.
Nowadays, Concord grapes also grow in the wild all over many parts of the Northeast. And when summer turns to fall, you can find them in stores and farmers’ markets if you’re lucky.
A few facts about Concord grapes:
- Concord grapes are a dark purplish black, and are often covered in a light layer of harmless white bloom.
- They’re usually less sweet than traditional grapes.
- Concord grapes are also a “slip-skin” variety of grape (as opposed to “fixed-skin”), which means that they pop right out of their jackets when you give them a little squeeze.
- They’re generally used for juice and jam or jelly, not for eating out of hand because they have big seeds.
- Folks also put them into pies and tarts, like this.
Notes on timing, pectin, and canning
The timing on this recipe is imprecise at best, and will depend on your particular batch of grapes, specifically on how much pectin they had. Fruit loses pectin as it ripens. (And pectin is the stuff that thickens jam.) Concord grapes don’t have a ton of pectin, and each batch will be slightly different. For that reason, this recipe also relies on reducing the jam to thicken it.
The bottom line? Cook the jam for 20 minutes as I indicate, then check it and cook it a little longer if it’s not done. Keep reading, I’ve included just what you need to look for.
Also, this recipe makes about 4 pints, which is a relatively small amount of jam. I just keep it fresh in the fridge, where it will be happy for weeks—if it lasts that long.
For instructions on how to properly can jams and jellies, take a peek at these instructions from the good folks over at Ball.
Concord Grape Jam
3 lbs. concord grapes
3 cups sugar
2 Tbls. lemon juice
Yields about 4 pints
Skin the grapes
This is a pain to do, but it goes faster than you think it will. It’s also kind of gross, but kind of fun. If you have kids in the kitchen, they’ll make perfect little helpers.
Grab a grape. Remove the stem. Give it a gentle squeeze between your thumb and first two fingers. The skin will split, and the meat of the grape will pop right out.
Do this over a bowl, so you can catch the juice that the grapes give off. There’ll be a fair amount of it and you’ll want to toss that into the jam pot with the fruit.
Keep the grapes in a bowl…
…and set the skins aside in another (or just heap them in a pile, like I did). Repeat until you’ve skinned all your grapes.
Puree the grape skins
Once all your grapes are peeled, put the skins in the food processor. (I’m reasonably sure a good blender would work for this, but haven’t tested it.) Toss in 1 cup of the sugar.
Process them on high for a minute or two. The skins will combine with the sugar and completely liquify. This is fun and feels like magic. (Hey, it’s the little things!) It happens almost instantly, and is delightfully shocking to see. Be careful from this point on. This stuff stains like mad.
The mixture will be thick, like this, and flecked with bits of grape skin. That’s just fine. You’re going to strain the mixture eventually. (Give it a taste. It’s heavenly already.)
Cook the Concord grape jam
Put the pureed skins in a medium-sized, heavy-bottomed pot. Add the peeled grapes.
Add the lemon juice, as well.
And the remaining 2 cups of sugar.
Stir the whole mess up to combine it well.
Set the pot on the stove over high heat and bring it to a boil. Stir occasionally.
Once it boils, drop the heat low enough so that the jam maintains a simmer—but doesn’t rapidly boil.
Cook like this for 20 minutes, stirring frequently. Keep an eye on the heat. If the jam feels like it’s sticking to the bottom of the pot when you stir, lower your heat a little. (If you keep the heat too high, it will scorch and your jam will have a burnt taste.)
After 20 minutes, your jam will have thickened and reduced, and should look about like this:
Strain the jam
Before you start, grab a plate and put it in the freezer. You’ll need it to test the jam in a few minutes.
Set a large, heatproof bowl on the counter. Fit a strainer on top. Pour the jam through the strainer, into the bowl. Be very careful when you do this. It may be delicious, but boiling hot jam is like napalm.
With a spatula, push the jam through the strainer. Keep smooshing it until most of the jam is in the bowl, and you’re left with a lump of seedy pulp in the strainer, like this:
How to test the jam for doneness
This is the part where the recipe gets a little imprecise. Now, at this point, your jam should be pretty thick. But the question is: Is it thick enough? Let’s find out. (A note for my buddy Jeff over at A Dork and His Pork: Yes, I switched spatulas at this point.)
Grab that plate that you just stashed in your freezer a few minutes ago. It should be very cold to the touch. If it’s not, stick it back in until it is.
When your plate is cold, drop a spoonful of hot jam on it in a little puddle. Pop the plate back into the freezer for 1 minute. (Yep, just one minute will do the trick.)
After 1 minute, yank the plate out. Tip the plate on its side. The jam should stay where it is in a blob, not run down the plate. Next, scoot the jam a little with a finger. The jam should have a skin that wrinkles up, like this:
If your jam passes both these tests, it’s done! If it’s still too thin, take the strained jam and simmer it for another few minutes. Then test it again. Repeat until it’s thick enough.
Jar, serve, and enjoy!
Ladle your warm jam into clean, sterilized jars. Let them cool to room temperature, then cover them and pop them in the fridge.
Peek into a readers’ kitchens as they make this jam
Update—October 13, 2009—A special thanks to Sheldon, who made a huge batch of this jam from Concord grapes in his own yard. He was kind enough to send me the video he and his son made.
Here’s what he wrote:
“This is a video my son helped me make – turning 12 pounds of the Valiant strain of Concord Grapes into jars of jam. I found that every pound of grapes took one cup of sugar (and a bit of lemon juice) yielding one 250 ml jar of jam. It wasn’t too sweet…in fact just a bit tart, but really is one of the best jams or jellies I’ve ever made.
A very special thank you to Jessie at the Hungry Mouse for her wonderful, easy to follow and well illustrated recipe. Here is a link to that page, which I had opened the entire time I was making the jam.”
And here’s his video.
Oh, he also canned it in a traditional water bath. Some of you have asked how that works out, and it looks like it’s just fine! He didn’t add any additional ingredients (no Certo or Surejell).