Grapefruit Jam


I have a bad habit of buying a mountain of fruit without much of a plan and then letting it sit around while I ponder and research. It doesn’t get me into too much trouble this time of year since apples, pears and citrus can store fairly well. It becomes more of a problem during the summer months, when things ripen at lightning speed.

grapefruit jam

When I came across a tower of red grapefruit priced four for $1, I bought eight, figuring they’d keep until I determined how to deal with them. I tucked the bag into the back of the fridge while I considered marmalades, curds and jellies. By the time I came back to it, more than two weeks had passed. Thankfully, grapefruit are sturdy and so they didn’t suffer too terribly in the interim.

grapefruit jam

Because the fruit wasn’t organic, I decided against marmalade (always best not to use the whole fruit if you don’t know how it was treated) and instead opted for a grapefruit jam. I was inspired by the filling I made for this citrus tart a few weeks back. I also happen to love the flavor of grapefruit and I was hopeful that it would translate well to a spreadable preserve.

grapefruit jam

When it comes to grapefruit, I’ve never been one of those people who cuts it in half, carefully dusts it with sugar and digs it with a spoon. I eat ’em peeled and segmented, just like an orange. It’s a little messy, but truly, there’s no way to deal with a grapefruit that isn’t just a little messy.

grapefruit jam

This recipe makes two pints (or four half pints if that’s your preferred measure). It’s a little bit of work to supreme the fruit (instructions here), but once that part is done, it cooks up in about 20 minutes like so many speedier jams. Spread on a buttered English muffin, it’s delivers the grapefruit flavor nicely, without the bitterness you get from marmalade. And though I like a hint of bitter on occasion, I was entirely fine not to find it here.

Small Batch Grapefruit Jam

Yield: 2 Pints


  • 8 large red grapefruit (approximately 4 pounds)
  • 2 1/2 cups granulated white sugar


  1. Start by supreming the grapefruit. Do this by cutting the top and bottom off. Then, working from north pole to south, cut the rind off the fruit (you want to expose the interior surface of the fruit). When rind is entirely removed, use the knife to separate the fruit from the membrane of the fruit.
  2. Collect the naked fruit sections and their juice in a large bowl. Set any seeds you find aside. Bundle them up in a length of cheesecloth. They’ll give the jam an extra hit of pectin.
  3. Once all the fruit is supremed, pour it into a large, non-reactive pot and add the sugar and the cheesecloth bundle containing the seeds. Stir until the sugar begins to dissolve.
  4. Turn the heat to high and bring the fruit mixture to a boil. Cook at a bubble, stirring regularly, until the jam reaches 220 degrees and passes the plate/sauce/wrinkle test (remove the pot from the heat source while you’re testing to prevent scorching).
  5. When the jam passes these set tests, pour into prepared jars. Apply lids and rings and process in a boiling water bath for ten minutes.
  6. When time is up, remove jars from canner and let them cool on a folded kitchen towel. When jars are cool to the touch, remove rings and test seals. Store sealed jars in a cool, dark place. Any unsealed jars should be refrigerated and used first.

Related Posts:


64 Responses to Grapefruit Jam

  1. 51
    Gwendolyn says:

    I made a batch of Meyer Lemon Jam with this recipe like you suggest in another blog post. I supremed about 20 lemons since that worked out to be roughly 4 pounds. I think I made have overdone it though? It’s very puckery sour! Next time I will definitely be adding more sugar…one cup more? What do you suggest?

    • 51.1
      Marisa says:

      Anything made with lemons is often quite tart. You can increase the sugar to taste. Whatever works for you!

  2. 52
    Derek says:

    I’ve made several citrus jams over the past month and all of them seem to be “tacky”. Is that normal for citrus jams? I’ve made hundreds of jams but none are tacky like these citrus.

  3. 53
    vvoman says:

    Mine refuses to set, at all. It’s not even vaguely thick. I’m going to redo it soon, we’ll see what happens I guess.

  4. 54
    jennifer says:

    I tried this recipe and at first it would not set. But after about 30 minutes it set rapidly. Now I have jars of Jam that I can not spread because its too stiff. I placed a jar in the refrigerator and it turned to one solid block. (The temperature while cooking stayed under 200 until it suddenly set and then it shot up to 220). Is there any thing that can be done to salvage the batch? Or maybe use for another purpose?
    I am interested in trying recipe again, If I can get this right I just know that the jam will be wonderful tasting. Any thoughts? Thanks!

    • 54.1
      Marisa says:

      The only thing you can do for the overset batch is to thin out each jar with a bit of water before serving. Or you can call it a fruit paste and serve it with cheese, the way you would membrillo.

  5. 55
    Mary McCreadie says:

    Since grapefruit can vary in size, could you estimate net from supremed grapefruit? Would 6 cups we enough?

  6. 56
    Mary McCreadie says:

    Aaand my grapefruit were VERY juicy. More juice than fruit sections, does that matter?

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.