Tuesday March 13th 2012, 11:04 pm

making marmalade using mixed citrus fruits

The big citrus preserving fest is just about over now. The Seville oranges have finished for the year and though there is always some citrus fruit available to buy all year round, with a plentiful supply of rhubarb just around the corner, I’ve had quite enough of the colour orange and am ready to don my rose tinted spectacles. Actually I haven’t made too much marmalade this year for one reason or another, but full of the usual good intentions still managed to buy the fruit anyway.
So time to clear the decks. That bowl of kumquats that I searched so earnestly to find, that pomelo that has sat patiently in the kitchen for the last few weeks and the handful of ruby oranges that I had almost forgotten were there, all need using up pronto. And then there are unwaxed lemons, 2 limes with peel starting to yellow and 3 bog-standard oranges that somehow got mixed in with the blood oranges at the fruit and veg shop. Oh, and a few bitter Seville oranges too. So to celebrate the last of the citrus why not use the whole lot in one fell swoop.
In some ways a recipe for this fruit-medley marmalade isn’t necessarily that useful to anyone else as the chances of you having the same mixture of fruits may be unlikely and the idea of going out with a shopping list for this exact combination fruitless. But knowing some basic principles for making marmalade is useful and can encourage everyone to use what they have as well as give you confidence to do your own thing if you fear stepping outside of the box. If that all sounds too much like hard work, by all means follow the recipe to the letter or sample a marmalade made earlier; pink grapefruit, rhubarb and cardamon marmalade or gooseberry and lime marmalade or perhaps lemon, fig and lavender marmalade, which is a good one for making just about any time during the year.

leaving peel and pulp to soak overnight to boost the pectin

I love marmalade with a tart edge to it rather than being too sweet, so using bitter oranges suits me down to the ground. There is a difference between a bitter marmalade and a BITTER marmalade, the latter caused by the inclusion of the fruit’s pith. An overpowering unpleasant bitterness somehow coats the inside of your mouth and stays with you for ages after you’ve eaten your toast! I also love peel in my marmalade, lots of peel. Without it marmalade would simply be jelly! Hand cutting peel can be a tedious part of the process and it is hard to get a really fine even cut. For me this is all part of the ceremony of marmalade making, though luckily I don’t make huge batches. I do have a special bean shredding attachment for my Kenwood Chef which can do the job neatly, easily and quickly, though rarely use it, but if you intend to make marmalade big time it might be worth finding something similar to streamline the job.
The peel needs to be really well cooked first, seemingly overcooked, as it candies and hardens once it is boiled in the sugar syrup. Jane Hasell-McCosh, who founded and organises the annual Marmalade festival at her home, Dalemain Mansion, Nr Penrith, told me that undercooked peel is the most common reason for entries being marked down. The peel should first be cooked until when pressed between finger and thumb it disintegrates, and that can take between 1-2 hours of slow cooking to achieve. Of course, if you like a chewier texture, cook it for less time but don’t expect any rosettes for your efforts.
Different kinds of citrus fruits contain varying amounts of pectin, the stuff that helps jam to set, so you do need to do whatever you can to make the most of what pectin there is. Tying pips and pith into a bundle with muslin and soaking them with the peel in the water or juice overnight helps to extract the available pectin. I have never found it necessary to add extra pectin to my marmalade.

making marmalade using mixed citrus fruits

Use your own combination of citrus fruits. You could include grapefruits, mandarins and sweet oranges as alternatives. Roughly match the total weights shown in the recipe but don’t get too hung up on matching measurements exactly.


Makes approx 1.25Kg (4 x 1/2 pint jars and a bit)

Fruit with combined weight approx 1240g (2 3/4lbs):
kumquats (325g / 12oz)
1 pomelo (465g / 1lb)
3 Seville oranges (325g / 12oz)
1 lemon (125g / 4 oz)

300ml (1/2 pt) mixed citrus fruit juice (I used blood oranges and limes, close to past their prime but still full of juice)
1.2ltrs (2 1/4 pts) water
approx. 800g (1 3/4lbs) sugar

Wash and scrub all the fruit and drain in a colander. Cut the kumquats lengthways into quarters and remove and collect the pips. Remove the peel from the pomelo, Seville oranges and lemon. Pull away the thick pith from the pomelo and any from the oranges and lemon that comes away easily and discard it, then roughly chop the flesh from the fruits, collecting it together with any juice and the kumquat pips. Finely chop the peel into shreds. This made approximately 360g (12oz) chopped peel and 750g (1 1/2lbs) pips and flesh. Wrap the pips and flesh into a bundle with muslin tied securely with string.
Place the peel, muslin bundle, juice and water in a bowl and leave to soak for 12-24 hours. Put everything from the bowl into a pan with a lid, bring to a simmer and cook gently until the peel is soft, which may take 1 – 2 hours. Remove the muslin bag, collecting any liquid that drips from it. Separate the peel from the juice by pouring through a sieve over a bowl, then measure and weigh them both separately.

At this stage it made 700ml (1 1/4pts) juice and 480g (1lb) cooked peel. To calculate how much sugar I needed I made two calculations; one for the amount of juice and one for the weight of the peel then added them together. I choose a classic sugar to juice ratio as used for making a jelly of 400g (14oz) sugar to every 600ml (1 pint) juice = 460g (1lb), plus 70% sugar to weight of peel = 336g (12oz). 460g (1lb) + 336g (12oz) = 796g Rounded up to 800g (1 3/4lbs).

Prepare clean jars and lids by sterilising them in a low oven, keeping them warm till needed. If you plan to can (water process) your marmalade, prepare the water bath and jars and place jar seals in a pan of hot water on the hob.
Place the peel, juice and sugar in a preserving pan and stir over a gentle heat until the sugar is dissolved, then turn up the heat and bring to a rolling boil until the marmalade reaches setting point (a blob of the syrup on a plate quickly forms a skin that wrinkles when you push a finger over it). This took me about 10 minutes to achieve. Skim if necessary and allow the marmalade to cool for 5-10 minutes then stir to distribute the peel. Pour the marmalade into hot jars and seal. If you are canning your jam, process for 5 minutes then remove from the canner. Leave till cold, then test the seals. Don’t forget to label and date your marmalade.

What a wonderful post, you answer many of the little questions that niggle me on my infrequent visits to marmalade making, I never knew the sugar to peel ratio bit, never seen it anywhere. Thank you so much 🙂

Comment by Joanna 03.14.12 @ 9:49 am

Joanna, the 70 percent sugar to peel ratio is in fact quite a low amount. Generally recipes match sugar to fruit 100 percent. Also often people think ‘more sugar makes more jam’ but what you end up with is too sweet! The sugar is a preservative though, so adding plenty is a safe way to do things but doesn’t make for the best tasting jam.

I set out how I calculated how much sugar to add. I don’t believe there is a set way to do this, this is just how I approach things based on my knowledge of the subject.

For a jam / marmalade to keep well (without canning it) it needs to have a 60 – 70 percent sugar content, which isn’t simply based on how much sugar you add. It also takes into account the sugar content of the fruit used. To work this out you need a refractometer to take a Brix reading, which measures the refraction of light through a sugar syrup!

This marmalade has a Brix reading around 68 percent, so is pretty spot on, (could possibly have less sugar added,) and it should store perfectly well without canning.

This all takes jam making to a more complicated level but I’m always aiming for the perfect formula, so the preserve I end up with is more then just fruity sugar but instead captures the absolute flavour essence of those particular ingredients. It is all about respecting the ingredients not just boiling them to bits! That is what makes preserving amazing.

Comment by laundryetc 03.14.12 @ 10:24 am

Hi Gloria. I’m interested in what you say about the refractometer. I’ve never used one but have heard they are accurate. Do you always use one? if so, which make and model would you recommend? I make preserves on a small scale and would be interested to know more about this. Thanks.

Comment by Rachel Baker 03.14.12 @ 2:03 pm

Well done you for getting around to the marmalade despite all odds. I never really end up making as much as I want: cue Maggie Smith in Gosford Park turning her nose up at “store-bought”.

This is a great post; one might go so far as to say the definitive post on marmalade.

But I guess that means you didn’t enter anything at the Marm Fest?

Comment by Sarah B. Hood 03.14.12 @ 2:41 pm

Rachel, I found it quite hard to find information regarding how to use a refractometer. In the UK if you plan to sell jam and marmalade, you have to follow the trade description guidelines, where those products have a specification. Also you will see that all preserves sold, apart from charity sales etc, have the sugar content stated on the label, by law, and you need a refractometer to know this.
I check the sugar levels when I’m developing recipes, so I know there is enough sugar so the jam will store without canning (water processing) as we don’t generally do that to our jams in the UK. If you can your jam you can use less sugar than conventional recipes.
My refractometer is made by Greiner, which is a well known reputable make. I bought mine from Germany but I’m sure you can get them in the UK. It is important to buy a refractometer that covers the correct range for what you need as they are used for things other than making jam. Think the one I have goes from 0 – 90. This will make sense when you start looking at them. Do a search on ebay for example and you’ll see what I’m talking about.
If you are repeating tried and tested recipes, you can use a refractometer to tell when you’ve reached the correct setting point and the sugar percentage is exactly what it should be. See this article about Rosebud Preserves (starts Pg 79) Elspeth Biltoft always uses a refractometer to know when her preserves are ready. Hope that helps.

Comment by laundryetc 03.14.12 @ 2:52 pm

I’d decided to hang up my jam and marmalade making apron, but between you and Shae, I might have to emerge from retirement. Your marmalade looks delicious.

Comment by Denise | Chez Danisse 03.14.12 @ 5:30 pm

Great post Gloria. I love Marmalade. The weights and tips on how much sugar is great.

Comment by Bonnie 03.14.12 @ 6:26 pm

Lovely to read abut the new season. Not a fan of marmalade, but keen to know more about rhubarb, mine is just begining to push through.

Comment by hilary 03.15.12 @ 4:34 pm


I am really inspired by this post to buy a refractometer, but still confused: should the refractometes scale really start from 0%? So only the 0-90% is good for us? an 50-90% isn’t enough?And after that, what are the setting points in brix scale? where can I read more about making jams/jellies with a refractometer?

thank you very much!


Comment by eszter 03.19.12 @ 12:04 pm

Hi Eszter – My refractometer is 0-90% and is sold specifically for preserving. I have found it very difficult to find information about using a refractometer, and I’m generally good at research! Sorry I don’t have any more information to give you. If you find out more I’d love to know too.

By the way, love the images on your blog and wish I was able to understand the language. Good luck.

Comment by laundryetc 03.19.12 @ 12:18 pm

oh, ok! I’ll try to find some info than. (but for beginning: this 68% what you mentioned earlier in your comment is a good setting point for this marmalade?
(thanks for your kind words! I quickly installed a google translator for my page (in the header area, sorry a bit messy, but works :))

Comment by eszter 03.19.12 @ 1:19 pm

Will depend on what combination of citrus fruits you are using Eszter. I got a firm set and for me it could have been slightly softer. If I had boiled it for a shorter time (few minutes less) then the sugar content would have been lower. Unless you are repeating recipes the sugar content measurement will help indicate chances of keeping without canning. Also if sugar content is too high, then the jam will be liable to crystalise whilst stored.

Comment by laundryetc 03.19.12 @ 4:42 pm

Great post and timely–I have a flat of meyer lemons on the way, even though I went a little crazy marmalade making this year!

Comment by Sara 03.21.12 @ 8:19 pm

You are an inspiration. I have only just found out about a refractometer, I have ordered one and can’t wait to getting closer to the perfect set!
Thank you so much for taking the time to post all this info!

Comment by Bluebell 08.27.13 @ 8:00 pm