Mixed Citrus Marmalade

In the room at the back of the house next to a sunny patio door lives my orangery. Two potted citrus trees.

The older is a Calamondin (Citrofortunella Mitis). This small citrus is thought to be the result of a cross between an orange and a kumquat, and its fruit are used extensively in Filipino cuisine. Its one of the commonest type of potted orange trees sold as houseplants.

The younger is a Meyer Lemon. This one is thought to be a cross between a lemon and an orange and produces lemon-shaped fruit that get a blush of orange on the skin when they ripen, and are sweeter than ordinary lemons.

A third tree waits in the wings on the kitchen windowsill. An australian immigrant - Fingerlime (Microcitrus Australasica). It is still very small - having arrived as a seedling earlier in the year - and is currently just about getting ready for its first repotting. It will be a few years before it is big enough to start flowering and producing its unusual fruit.

This year's citrus crop came to a total of about 1lb of fruit from the two fruiting trees. By themselves that would make only a very small batch of marmalade, so I padded them out by adding 6 limes and 6 oranges from the supermarket.

On the first day:

Wash all the fruit, and dry them off.

Take a large glass mixing bowl and another small bowl.

On a plate - so you can collect the juice - thinly slice the calamondins and meyer lemons, peel and all (they have quite thin peel with little pith). Put any seeds you may find in the small bowl, and then put the sliced fruit and all juice into the large bowl.

Next, cut thin strips of zest from all over the limes and oranges and add these to the bowl.

On the plate, quarter and finely slice 3 of the limes. Add the fruit and juice to the large bowl. Squeeze the remaining 3 limes thoroughly and add the juice to the large bowl. Slice up the squeezed lime halves and add them to the small bowl with the seeds.

Peel the remaining zest and pith from 3 of the oranges and put it into the small bowl, and then quarter and thinly slice the 3 oranges into the large bowl. Squeeze the final 3 oranges thoroughly and add all the juice to the large bowl. Cut up the squeezed oranges and add them to the small bowl.

Tip the contents of the small bowl - all the pips, pith and squeezed out fruit - into a muslin bag and tie shut. Put this bag into the large bowl too.

Boil a kettle and pour hot water over everything in the large bowl until the water level just covers all the fruit in the bowl. Place a small ceramic plate on top to weigh down the muslin bag and keep it under the water surface.

Cover the bowl with a clean teatowel to keep out fruit flies, and leave the fruit to soak overnight.

On the second day:

Microwave the bowl on full power until it is bubbling. Cover with the teatowel again and leave to stand.

At this point it got forgotten about for a day, so...

On the third (fourth) day:

Microwave the bowl on full power until bubbling again. Test a piece of zest to ensure that it is soft and cooked, and microwave some more if not.

Once the zest is soft, let it stand a few minutes until the muslin bag is cool enough to handle. Squeeze the juice and pectins out of the pith and pips through the muslin bag into the bowl. Get as much out as you can, then discard the contents of the muslin bag.

Weigh the fruit and juice in the bowl, and then tip it into a maslin pan. Add the same weight in sugar. Warm gently and stir to dissolve the sugar in the juice.

Once all the sugar is dissolved, turn up the heat and boil until jam setting point is reached.

Let cool for a few minutes, then stir to distribute the pieces of zest and fruit through the jam. Spoon into heated sterile jars and seal in the usual way.