Jam is such a wonderful thing – especially when home made. We have a good stock of my rhubarb and vanilla jam and this lovely plum jam on our shelf which should see us through this winter.
It appears that people have been making jams for a long time – the first jam recipes appear in ‘De Re Coquinaria’ (The Art of Cooking), a collection of Roman recipes dating from the 1st century AD. Then, the simplest jams consisted of soft fruit heated with sugar or honey which were cooled and stored as a way to preserve fruit. Jams were first brought back to Britain from the Middle East by returning Crusaders in the medieval period. Perhaps there is something about jam and wars – Joan of Arc is supposed to have eaten quince jam before going into battle as it filled her with courage. Maybe I should find a recipe (and some quinces) and make quince jam to put on my toast when I’m facing a particularly busy week at work?
Photos by Jonathan Pielmayer and Sam Edwards on Unsplash
Large-scale jam production became possible after ~1795, when a Parisian pastry chef, Nicolas François Appert found that putting food in sealed containers and heating them in a bain-marie effectively sterilised the contents and protected them from external contamination. Any scientists who enjoy making jam are in good company – one website I read suggests that Marie Curie enjoyed making jam in her spare time.
Making your own jam allows you to reduce the amount of sugar – the jam may well be runnier, but I reckon the taste is just as good, if not better. And I have no difficulty storing it for as long as we need…. The original recipe called for ~1.25kg sugar for 1.5kg of plums, but I’ve almost halved that here.
Plum jam (pdf Plum jam)
1.5kg ripe plums
750g jam sugar (you can use ordinary sugar but jam sugar will help with the set)
Makes approx 4 x 450g jars (I always have more, and a variety of sizes handy)
- Put some clean jam jars in an oven at ~100 degrees to sterilise.
- Halve and stone the plums and put into the preserving pan with 400ml water. Bring to a simmer and cook gently until fruit is tender and the skins are soft (usually around 20 minutes).
- Add the sugar and stir until it dissolves.
- Once the sugar is dissolved turn the heat up and boil rapidly until the jam reaches it’s setting point* – usually about 10-12 minutes. Stir occasionally to prevent sticking and skim off any scum as you go. You can add the juice of a lemon to help the set if this doesn’t seem to be happening!
- Remove from the heat – if the fruit is bobbing about at the surface it probably needs a little longer. Bottle in the warm jars. Place wax circles on top and then put the lids on tightly.
- Enjoy on toast, scones etc…..
*To test for a set – put a saucer in the fridge before you start and put a dollop of jam onto it. Allow to cool for a minute. If it wrinkles when you push it with a finger it has reached setting point. Jam should be removed from heat while you check for a set. If you have a suitable preserving thermometer you could use this instead – setting point is about 104.5 degrees.