Roasted Seedless Grape Jam

September 29, 2017(updated on August 30, 2021)

Our intrepid contributor Alex Jones is back with a recipe for roasted grape jam. Just reading this post makes my mouth water!I can’t even imagine how good her kitchen must have smelled during the roasting process! -Marisa

I didn’t taste a Concord grape until I was in my late 20s and buying them from local Pennsylvania farmers to share with members of the Greensgrow CSA. And once I had — while I finally understood what “grape” flavor is meant to emulate — I just couldn’t get down with the seeds. They were too much work to snack on compared to the fat, juicy table grapes I’d grown up with as a kid in California.

So imagine my delight when I found out that when Lem Christophel, a Mennonite who runs Eden Garden Farm in Dillsburg, Pennsylvania, brings grapes to my local farmers’ market, they are completely seed-free.

I love them for snacking (these days, I try to leave the California produce as a special treat to help me get through the depths of winter), and last year, I made possibly the most delicious raisins I’ve ever had by steming a few bunches and throwing them in the dehydrator. But I’d never canned them before.

Last Saturday, I got my chance: a big rainstorm had passed over Lem’s part of the state, and some of his juicy red and purple grapes had split right before harvest. Lem knows I’m a preserver, so he tempted me with a great deal  — five pounds for $10 — and, of course, I caved.

After thoroughly stemming, picking, and washing my stash, I had three pounds of good fruit to work with. But I wanted to do something a little different than the jelly or smooth-milled jam that comes from seeded grapes. I settled on roasting the grapes — a mix of standard-sized dark purple specimens and small, spherical reds — in the oven with a little honey to intensify their flavor.

They roasted at 425oF for a little under half an hour — my oven runs cool, so I recommend checking at 15 and 20 minutes so you don’t end up with a burnt mess. I pulled the pan out when the grapes started to give up their juice and the skins began to wrinkle.

Post-roast, I had eight cups of juicy cooked grapes, which, once buzzed up in my Dutch oven with the stick blender, gave me around four cups of slightly chunky pulp. Using the ratio from Marisa’s Concord grape jam as a guide, I added roughly half that volume of sugar (two cups) and squeezed in half a lemon.

I cooked down the mixture until it looked nice and dark and thick and the apartment was infused with a juicy grape aroma. Then the mixture went into jars and then the water bath canner for 10 minutes.

(One important note: Although I was checking temperature with my instant-read thermometer and using the plate test, I got a little set shy and pulled the jam off the heat when the wrinkles in the jam on the plate had just started to show up and the thermometer still read just 219oF, so it’s a little saucier than I prefer. Go for the full 220oF and you should get a mixture that doesn’t require a spoon to serve.)

The next morning, I took the jam for a test drive over a few slices of coconut-acorn sourdough bread from my Fikira Bakery bread CSA that I toasted and smeared with a few spoonfuls of Valley Milkhouse’s creamy, tangy Clover, a fromage blanc-style fresh cheese.

The preserve is delicious — a little chunky from leaving some of the skins whole, bright and bold and a perfect distillation of seedless grape flavor. I can imagine spooning this over French vanilla ice cream or serving it with a punchy blue cheese and toasted walnuts.

I look forward to popping open one of the five half-pint jars I canned this winter and brightening up my morning. Maybe I won’t need those California grapes after all.

5 from 1 vote

Roasted Seedless Grape Jam

Servings: 3 pints
Author: Alex Jones


  • 3 pounds seedless red or purple grapes after picking through
  • 1/4 cup honey
  • 2 cups sugar
  • 1/2 lemon juiced


  • Preheat oven to 425 degrees F.
  • Prepare a water bath canner, five half pint jars, lids, and rings.
  • Wash, pick over, and stem grapes. (You should have approximately three pounds after stemming.) Toss the grapes with the honey and spread them in a single layer on a parchment-lined baking sheet. Roast for 25-30 minutes, until the grapes begin to give up their juice and the skins wrinkle.
  • Once cool enough to handle, put the grapes into a large measuring cup and blend with a stick blender to your desired consistency (I made mine relatively smooth with some big chunks still in there). You should have around 4 cups of grape puree.
  • Place the puree, sugar, and lemon juice in a heavy-bottomed pot. Bring to a boil over medium-high heat, then cook, stirring frequently, until the jam passes the plate test or shows 220 degrees F on an instant-read thermometer.
  • Remove the jam from the heat and funnel into prepared jars. Wipe rims, apply lids and bands, and process in the water bath canner for 10 minutes. After canning, allow the jars to sit for 24 hours. Check seals, remove bands, label, and store.

Sharing is caring!

Leave a comment & rate this recipe

If you enjoy this recipe, please do give it a star rating when you post a comment. Star ratings help people discover my recipes. Thank you!

Your email address will not be published. Required fields are marked *

Recipe Rating

11 thoughts on "Roasted Seedless Grape Jam"

  • Funny, I’ve seen Thomcord grapes at my market – they’re seedless Concord-style grapes from California! My kids love them.

  • Second year in a row using this recipe. It’s the only one I trust for my own Concord grapes, and the honey I harvest from my bees. Family and friends love this as a gift. Off to make more! Happy Holidays!!!

  • Hi Marisa,
    What was the reason you decide to roast the grapes first? Does it give off a touch of roasty flavor or just to get rid of its juice ?

    1. Typically grapes need to be cooked and food milled/pureed before you can proceed with making anything with them. You can either do this by simmering on the stovetop with a little water or roasting. Either technique is fine. This recipe was developed by a contributor and she opted for roasted to help concentrate the flavor. It definitely gives them an enhanced sweetness.

  • 5 stars
    Loved your recipe. I added 6 oz. of fresh cranberries to give it a little tartness. It was
    delicious! Thank you for the oven roasting idea. I plan on trying this method for some other jams. 😁