Ruby grapefruits have such a beautiful color. I buy them in bulk and love to put them in my juices (this is my favorite grapefruit juice combination!) I also adore jams and marmalade and found myself craving a grapefruit marmalade. I thought that canning would be a great way to capture their lovely pink hue and would mean I would continue to have access to it throughout the year. I used to be scared of making jams and jellies, but it really is so simple, and is a wonderful way of capturing the flavor of fruits and vegetables at the height of their season.
Unfortunately, I didn’t write up this blog post when I originally made my first batch of this marmalade. I just made a small batch, maybe about 4 half pint-sized jars, and as I started to write this post, I realized that I had actually either given away all the pots as gifts, or eaten them myself, and so couldn’t photograph the end result. Oops. Well …. so here we are making it again! Not really such a chore, as it happens.
First you will want to sterilize all your equipment: wash and rinse eight half pint jars and their lids, a jam funnel and a ladle. You can do this a number of ways – I usually boil the jars for 10 minutes, or you could also put them in a hot oven, or even run the sanitize program on your dishwasher.
This marmalade is quite soft set – and you can make it stiffer by boiling it for longer. Making the end result a cross between bitter and sweet is key when it comes to marmalade. You need the fruit, sugar and the peel – but you really don’t want the pith – it adds an unsavory flavor and will mar the finished look and taste of your marmalade. When you are chopping up the fruit, make sure you remove all the pith. You want the flesh and the skin only. I usually use a citrus reamer, or a vegetable peeler to very thinly peel the grapefruit. You may end up with a little pith – not a big deal – but try and get as little as possible. The example on the right is what you are aiming for.
Place the peel (no need to chop up) in a small saucepan with about 2 cups of water and 1/8 t bicarbonate of soda. Bring to a boil and simmer for about 15 minutes. Strain and leave to cool. Cooking the peel first both aids in softening the peel, as well as releasing the pectin, so ensuring your marmalade will set correctly. Once cool, you have a choice here – you can either gather the peel up on a chopping board, and slice it thinly into shreds – or put it in the food processor and pulse until it’s as roughly or finely chopped as you like.
To prepare the fruit, cut a very small piece off the bottom off the grapefruit, so that it sits flat on the chopping board, and then cut from the top to the bottom of the fruit, cutting with the shape of the fruit – and this will remove all of the pith.
Now chop up the fruit: cut it into quarters and remove the tough line of pith down the middle; place in a food processor, along with all of the juice – making sure to remove any pips along the way. Grapefruit pips are large and there’s usually not many, so this is pretty easy. Pulse the fruit about half a dozen times, until the pieces are quite small (or again, you can keep it chunkier, if you prefer your marmalade with chunkier pieces – just pulse less times). You may need to do this in several batches.
Add the fruit to the jug with the pith – once it reaches the top, pour into a large saucepan. Keep measuring out the contents of the food processor, keeping track of the total volume of fruit and pith combined. In this instance, I ended up with about 9 cups total volume. Next, put the same volume of sugar into the pan, minus one cup – so I ended up putting in 8 cups of white, granulated sugar. Stir slowly to combine the fruit and the sugar. At this point, place about 4 small plates or saucers into the freezer. You will use these to check the set point of the marmalade a little later.
Turn on the heat to medium and simmer, stirring every few minutes until the sugar has completely dissolved – about 5 minutes. Next add the lemon juice, stir briefly and bring to a rolling boil. Turn the heat down to medium high, until the contents are bubbling away – but no longer rising up to the brim of the pan. Cook – stirring about every 5 minutes to ensure the bottom doesn’t start to stick – for 15 minutes. Start checking the set of the marmalade after this time.
Take the pan off the heat and take a plate out of the freezer and put a teaspoonful of jam onto the plate. Return to the freezer for 2-3 minutes and then test the set by pushing your finger against the edge of the marmalade. If it wrinkles, it’s ready. If not, return the pan to the heat and test again after 5 minutes. You may need to do this 2 or 3 times. In the picture above, the marmalade is still a little runny and does not wrinkle when pushed. I returned the pan to the heat for 5 more minutes and this achieved the set I like. The marmalade will thicken up just a little bit more once cooled in the jar for 24 hours. As I said, I prefer a soft-set marmalade – if you prefer a firmer set, then you will need to boil for a little longer.
Once the marmalade is ready, take the pan off the heat and leave to sit for a good 5 minutes. This will ensure the peel doesn’t sink to the bottom of the jars. Now, using a sterilized funnel and ladle, scoop the marmalade into the dried, warmed pots, leaving about 1/2″ headspace. Dip the tip of a sterilized knife along the edge and down to the bottom of each pot. Gently pull the knife towards the center and then remove it. This will ensure there are no air bubbles in the finished marmalade. Wipe the rims of the jars with a clean, moistened paper towel and rest the lids on top. Put on the bands and screw to hand-tight. Do not over-tighten at this point.
This next part is up to you – I always use a water bath to can my jams and marmalades. This means putting the pots into boiling water, making sure the tops are covered by 1″ water, and processing for 10-15 minutes. This will give the pots a shelf life of at least a year. This is generally not something that is done in the UK. However, standard practice in the US is to follow the canning process for safety reasons. This ensures all the air is removed from the jars and ensures the product will be safe to eat for up to a year. If air is allowed to enter the jars, then mold can grow. Any jars that have mold on the surface when opened should be thrown away. Mold here is likely to be botulism and can really make you ill. Scraping the top and removing the mold you can see is not actually removing all the mold spores. I’m also an advocate for using mason jars. Re-using old jam jars will never give you a perfect seal, and so be an invitation for bacteria to develop and spoil the batch.
After the canning process, re- tighten the lids firmly. When the pots are cold, press the center of each lid. There should be no movement when you touch the lids. Any lids that pop up and down when you push them (meaning they did not seal properly), should be put in the refrigerator and consumed within the month. Otherwise, keep in a cool, dry cupboard for 12-18 months.
Here’s a nice piece on the reasons why canning is important. There’s another useful link after the recipe.
- ** 3 or 4 saucers or small plates
- 8 large ruby grapefruit
- Sugar - see instructions for quantity
- Juice of 2 lemons
- First of all place 3 or 4 small saucers or plates into the freezer - you will use these later to check for the set of the marmalade.
- Fill a large canning pan with water and bring to a boil. ***
- In warm, soapy water wash your jam jars/mason jars and rinse. Place in the pan and boil the jars for about 10 minutes. Add the lids for the last 5 minutes. Turn off the heat and leave the jars in the water until just before you are ready to fill them with the marmalade.
- Using a citrus reamer, or vegetable peeler/paring knife, cut the peel away from the pith. Try and get as little pith as possible. A reamer works really well for this.
- Put the peel into a small saucepan with about 2 cups of water, and the bicarbonate of soda.
- Bring to a boil and then simmer for about 15 minutes.
- While the peel is simmering, cut all the pith away from the fruit.
- When the peel is cooked, drain and cool.
- Chop up the peel into small slivers if desired, or add the peel into the food processor and pulse the contents 5 or 6 times. Pulse to desired size. I prefer mine in quite small pieces.
- Empty the peel into a measuring jug.
- Put the pieces of fruit, plus all its juice into the food processor, picking out any pips as you go. Fill the food processor no more than ½ full. You may need to do several batches.
- Pour the contents into the jug containing the pith, to measure the volume.
- Put the fruit mixture into a large, heavy-bottomed pan, and continue pulsing the fruit, measuring the amount and adding it to the pot. Be sure to keep track of how much fruit and peel you have over all.
- Now add the same volume of granulated sugar, minus 1 cup, to the pot. (I had approximately 9 cups of fruit, so I added 8 cups sugar).
- Stir in the lemon juice, and bring the mixture to a rolling boil.
- Turn down the heat so that the mixture is still boiling, but no longer rising in the pan.
- Cook for about 15 minutes, stirring every 5 minutes or so to check it is not sticking on the bottom.
- After 15 minutes, remove from the heat and take out one of your saucers from the freezer.
- Add a small spoonful of marmalade to the plate and return to the freezer for 2 minutes.
- Check the set by pushing your finger into the edge of the marmalade. If the mixture wrinkles, then it is ready. If it is still runny, return to the heat for 5 minutes more.
- Remove from the heat and re-check the set as before - remembering to remove the pan from the heat while you check the set.
- You may need to do this several times. (Depending on how much juice versus fruit you had).
- Once the mixture wrinkles on the plate, let the mixture stand in the pan for 5 minutes. This will ensure the peel bits don't sink to the bottom of your jars.
- Take your jars out of the hot water and dry with a clean cloth/paper towel.
- Using a jam funnel, fill the jars to about ¼" from the top.
- Once you've filled each jar, run a knife down the jar against one edge until it touches the bottom. Pull the marmalade gently towards the center of the jar, then remove the knife. This will ensure there are no air bubbles in the marmalade.
- Put the lids on the jar and do them up firmly, but do not over-tighten at this point.
- Return the jars to the canning water and process for 10 minutes. ***
- Remove from the water and allow jars to cool on a rack.
- Once completely cool, re-tighten the lids.
- Check the seal by pressing the top of each lid. If they push in, they did not create a vacuum - so put these jars in the fridge and consume within 3 weeks.
- Store all properly sealed jars in a cool, dry place for up to a year.
*** Processing the Jars.
This is not something that is usually done in the UK. However, standard practice in the US is to 'can' the jars in a water bath for 10 minutes. This ensures all the air is removed from the jars and ensures the product will be safe to eat for up to a year. If air is allowed to enter the jars, then mold can grow. Any jars that have mold on the surface when opened should be thrown away. Mold here is likely to be botulism and can really make you ill. Scraping the top and removing the mold you can see is not actually removing all the mold spores.
I leave it up to you as to whether you feel you need to can your jams and jellies or not. Since I learned for myself about the dangers of not having a good seal (ie - you cannot guarantee the quality of a seal from re-suing old jam jars and their lids) I have always used the water bath method. Also, I give a lot of jars away as gifts, and this way I can be sure I am not going to poison anyone!
Here is another great piece on the wisdom of the canning process.