Recipe: Grapefruit Pectin Jellies

These jellies are basically the point of grapefruit, at least in my opinion.  I find grapefruit far too bitter to eat, but the bitterness and sourness help the pectin to set the jelly, and the resulting confection is just sweet enough, with a lovely grapefruit flavour and only a hint of bitter pith.  If you like other citrus but have never liked grapefruit, give these a try.  You’ll be surprised at how nice they are.

This recipe is actually extremely easy to make – the biggest difficulty in my experience is finding the right kind of pectin.  Well, that and not having exploding thermometers or scales which spontaneously malfunction.  The pectin you can buy at most supermarkets or health food shops is for jam – confectionery requires a stronger pectin.  My pectin is labelled Classic CS 502, with a degree of esterification that is 58-64% and is designed for a soluble solids range of 68-80% and a pH range of 3.0-3.6.  I’m afraid I have very little idea what that means (clearly I need to read more of that food chemistry book), but it might give you something to look for on the packaging.

You also absolutely require good scales and a candy thermometer for this recipe.  I recommend avoiding glass thermometers – they can shatter, and there’s nothing worse than having your jelly all ready to pour into the tin and then realising that you only have half a thermometer and the other half is somewhere in the gel... especially when this was the first time you actually found the right pectin and got the mixture to setting consistency…

Your Shopping List

50 g + 350g sugar (plain white sugar is best here)
20 g pectin
zest and juice of 1 medium grapefruit (about the size of a largeish orange)
175 g glucose syrup (I think this is the same as corn syrup – it’s a clear, very viscous, very sweet liquid derived from corn)
10g citric acid solution (5 g citric acid dissolved in 5g just-boiled water)
caster sugar, to coat

Now what do you do with it?

Mix the pectin with 50g sugar, and put in a small-medium saucepan with the grapefruit zest.  Put the saucepan on your scales and set to 0, then pour in the grapefruit juice, whisking like mad – pectin likes to clump up.  Pour in cold water until the scales read 250g, still whisking madly.

Bring to a boil over low heat, whisking until everything is smooth. Theoretically one is supposed to simmer it for 2 minutes here, but by the time I’m done whisking it, I don’t usually bother.

This is the point where I let it boil up a bit and then add the sugar and glucose

Add sugar and glucose syrup and stir in briefly to disperse.  Incidentally, the easiest way to get glucose syrup out of a jar is with a spoon (or better still, fingers) that you have dipped in cold water – it doesn’t stick as much then.

Just after adding the sugars…

Boil the syrup without stirring until the temperature reaches 108°C.  While you’re waiting for it to get there, line a 19cm square tin with baking paper – this jelly sticks like you wouldn’t believe, so I usually do two layers at right angles to each other.

About 102°C… make sure your saucepan is large enough that it doesn’t boil over!

About 107°C – you can see that it’s getting  yellower and starting to darken at the edges

When the syrup reaches 108°C, take it off the heat immediately, and stir in the citric acid solution as quickly as possible, then pour the lot into the tin.  It will start solidifying as soon as you add the citric acid, so you need to be fast.

Let sit at room temperature for at least 3 hours, then cut into cubes or diamonds  (which is harder than it sounds – this jelly is quite tight and difficult to cut) and toss in caster sugar to coat.

Eat, with delight.

Pectin jellies – lemon on the left, grapefruit on the right


This recipe is obviously vegan and gluten-free, but if you’re trying to avoid sugar I’m afraid you are out of luck.  It keeps for months – I find the consistency of the jelly softens a little over time, but the outside becomes a little harder.

You can make it with any kind of citrus fruit – you just need to adjust things so that you get about 60-100g of fruit juice.  It’s especially good with blood orange and pink grapefruit, and wonderful with kumquat, apart from the fact that zesting and juicing kumquats is a very efficient route to insanity.  You’ll find that the consistency of the jelly varies with the acidity of the fruit. I’ve also made these with apple juice (rolled in cinnamon sugar) and with pomegranate juice – it will work with any nice, acidic fruit, but if you use just fruit juice, it burns easily.

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10 comments for “Recipe: Grapefruit Pectin Jellies

  1. Anne
    January 12, 2012 at 5:08 pm

    These are very very very yummy!!!

    • January 12, 2012 at 8:09 pm

      Thank you very, very much!

  2. Edie Devine
    December 27, 2013 at 6:41 pm

    I really want to make these, but I am confused about the recipe. The ingredients don’t list grapefruit juice—only zest and rind, but your instructions say to “…add the grapefruit juice…”. How much grapefruit juice—just from the one grapefruit? And then what are we to do with the “rind”? Your instructions don’t mention it.

    • Catherine
      December 27, 2013 at 8:39 pm

      Hi Edie,

      That would be because I had a moment of vagueness when writing this recipe and wrote ‘zest and rind’ when I meant ‘zest and juice’. Sorry about that!

      So yes, you want the zest and juice from just one grapefruit (and I just did it again and had to correct it!), and a fairly small grapefruit at that, or there will be too much juice. Make the juice up to 250ml with water – you don’t want it to be all juice or there will be too much sugar in the liquid and it will burn very fast.

      Hope this helps, and apologies for the confusion (I’ve corrected the recipe, too).


      • Edie Devine
        December 28, 2013 at 5:29 am

        Thanks for clarifying. I thought you meant juice, but I assume nothing! I’m so happy I found your blog. I’ve wanted to make these jellies since I had the most delicious jellies in Ireland this summer. They were so tasty and refreshing, without the fake and overly sweet taste that is common here in the U.S. That is what I am after. I tried two attempts a few months ago with what I could learn from different internet sites, but failed miserably. I figure that I needed someone to coach me that is experienced with these things. And sure enough, you have already said several things about the process that I found no where else that will make a big difference in how I go about it. So in January I try again. I may look to you for help…. . Happy New Year!

        • Catherine
          December 28, 2013 at 11:24 am

          Hi Edie,

          No worries at all! I’m very happy to be of help. And yes, it sounds like the jellies you had in Ireland might well be a similar recipe.

          Kind regards,


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