Kumquat and Lemon Marmalade using a pressure cooker

I have never made marmalade before and have always been put off by the seemingly  never-ending, tedious task of chopping, peeling, shredding, juicing, boiling, testing, etc. But when a friend told me about his method of making kumquat and lemon marmalade by soaking the fruit in sugar for a day, I thought I would give it a go. In his recipe, the kumquats are halved, the pips removed, and then combined in a bowl with lemon juice and sugar for 24 hours before boiling as normal.

My challenge, therefore, was to invent a recipe for a pressure cooker which would be even easier and quicker to prepare. A neighbour’s sister makes quince jelly in a pressure cooker by combining equal parts of fruit and sugar and then cooking for 3 minutes at pressure so I decided to experiment with times to see if this method would be possible for marmalade.

The first attempt was a success (although the cooking times needed tweaking) and I was really pleased with the consistency, texture and taste of the first batch. I had literally thrown everything in together (pips, pith and lemon quarters) but decided that for the second attempt I would tie the pips and lemon pith and skins in muslin to keep them separate.

It was clear that three minutes was far too short and I had to bring the cooker back up to pressure several times. So I decided that for the second attempt I would cook the marmalade for 15 minutes at pressure.

500g kumquats
2 large lemons
400g brown sugar or half the weight of the prepared fruit

Cut the kumquats in half, remove the pips and save on a muslin square. Cut the loquats into 2mm slices.
Peel the lemon rind with a vegetable peeler. Shred the rind into 2mm strips.
Put an empty bowl on the scales and weigh in the fruit and lemon juice. Add half the amount of sugar and mix well.
Securely tie up the lemon pith and pips in the muslin square and add toe the bowl of fruit.

Leave for 24 hours, stirring every so often. At the end of that time, the sugar will have completely dissolved and there will be quite a bit more syrup.

Transfer the kumquats and the muslin bag to a pressure cooker. Bring up to pressure and cook for 15 minutes. Remove the pressure cooker from the heat and slow release the pressure.

Open the pressure cooker and transfer immediately into clean glass jars using a jam funnel and a measuring jug. Turn all the jars upside down to sterilise the caps for about half an hour and then turn back the right way and leave to cool completely.

Scum-free strawberry jam

The finished product

1kg strawberries, hulled
500g jam sugar
1 teaspoon vanilla extract
1 knob butter

The method is the same as before but by adding a knob of butter, scum doesn’t rise to the top so much.

Scrunch the strawberries with your hands to mix the sugar well into the strawberries. Heat the strawberries to the boil in a wide, deep nonstick pan. Boil for 15 minutes and then put into sterilised jars.

This year’s first batch of strawberry jam

Strawberries and sugar

This year we had bought some jam sugar when we were in England so I decided to try it out with the strawberries I had picked today.

They weighed just over 1kg so I added 400g of jam sugar and scrunched them up with my hands in a bowl.

Strawberries with sugar juice

I poured the mixture into a frying pan and brought it to the boil. I left it to boil for another 10 minutes before pouring into clean, sterilised jam jars.

Boiling the strawberries

In previous attempts, I skimmed the foam from the surface but this time I didn’t bother. As they say in Spain “Si no mata, engorda” (= What doesn’t kill you will make you fat).

The end product

Strawberry Jam

The strawberries are now in season and producing lots so it would be a shame not to make the most of them. The only problem with jam-making in Spain is that you can’t buy jam sugar with added pectin and pectin only seems to be available in specialist shops in Madrid. This recipe therefore only uses normal sugar.

The first recipe produced a vibrant red more liquid version with the fruits holding their own better and and the second a more solid, paler jam which was not so runny. Jam-making is a work in progress and this page will be added to in the future. My ideal scenario would be to add some pectin – possibly pectin made a stock when the quinces come into season. The recommended amount of sugar for 1000g of strawberries was 500g sugar but in order to cut down on this we used 350g instead.

I think that the jam produced in the first recipe would be fantastic mixed with fresh strawberries or cherries for the topping for a cheesecake.


1000g strawberries
350g sugar

Mix the strawberries and the sugar and squeeze through your fingers to pulp.

Bring to the boil and boil rapidly for 6 minutes.

Pour into sterilised jars.

Immerse the jars in boiling water and cook for a further 10 minutes.



1000g strawberries
500g sugar
30ml lemon juice

Mix the strawberries, sugar and lemon juice together and squeeze through your fingers to pulp. As I was going to be boiling this recipe for longer, I didn’t want to mash the strawberries as much as in the previous recipe.

Bring to the boil and boil rapidly for 20 minutes.

Pour into sterilised jars.

Immerse the jars in boiling water and cook for a further 10 minutes.