photo by kind permission ©Alison Brierley
Jam is easier to make than most people think and definately a thrifty thing to do if your sister has a garden full of fruit trees.
English yellow plums are also know as Pershore plum or egg plums, can sometimes be a little pappy if you choose to eat them as a fruit but they make a truly wonderful jam. The Harvest time can vary depending on location and weather patterns but usually runs from mid August until mid September. When British yellow plums are out of season you can still find them in your supermarkets from warmer climates like Italy.
If you've ever tried to make jam and failed there are usually 3 main reasons:
The number one thing you need for successful jam making is an accurate thermometer.
Forget Grandma's set in a saucer method because it is too hit and miss,
Accurate temperature is the number one way to increase your chances of a jam that sets.
That does not necessarily mean an expensive one in fact I prefer the "pen" type that you can clip to your pocket just like a pen. The thermometer in this photo I have had for years.
If you live in the UK you can buy one here just for £4.80 + P&P
Or perhaps this one that has a useful clip on it so you can clip it to the side of your saucepan.
The second most important thing is sugar content, too little and it doesn't set, too much and it's too sweet. When I was putting together this recipe I originally tried using 2kilo of sugar for 1.5kilo of fruit and it set fantastically but was just too sweet. So my second attempt I cut the sugar in half down to the 1 kilo of sugar you see in my finished recipe. But my point is when you are trying a new recipe stick to it exactly!! before you start tinkering.
The third reason a jam can fail is low pectin content and to make it more complicated, different fruits have different levels of pectin. If you're lucky enough to have fruit trees in your garden you can presume that when the fruit is at its peak then the pectin level is at its highest. You can add extra pectin by using fresh squeezed lemon juice and skin*.
Yellow Plum and Vanilla Jam © Kevin Ashton 2014
1.5 kilos of yellow plum (destoned)
1 kilo of granulated sugar
1 lemon *(peel and juice)
28grams of unsalted butter
2 small vanilla pods
100ml cold water
1. Wash and dry your plums and then cut them in half and remove the stone. The easiest way I find to do this is to cut down from the top of the plum either side of the stone to give yourself 2 halves (as I have done in photo A). Then cut as much of the flesh off the stone (see photo B) so you don't waste any.
3. Place the plum flesh (remember my recipe calls for 1.5lkilo destoned weight) into a heavy bottomed stainless steel saucepan together with the cold water. Cover with a lid and heat the fruit with a medium heat. Remove the lid and stir the fruit every couple minutes to make sure it isn't sticking to the pan. Cook until the fruit is just tender and remove the lid and then add the sugar, lemon juice and lemon peel. Stir well until the sugar has completely dissolved.
4. Cut the vanilla pods lengthwise, scrap out the vanilla seeds and add to the jam, stirring them in well. Now add the unsalted butter and again stir in (the butter adds richness and also lessens the amount of foaming the jam produces. For the more experienced cooks you can also skim off any scum that floats to the top. The trick is to throw away the scum without throwing away half the jam. Removing the scum will help give you a clearer and shinier finished jam.
5. Continue monitoring the jam stirring occasionally until the jam reaches setting point 220F / 104C for at least 3 minutes. Once ready remove from the heat and remove the lemon peel, carefully pour the jam into clean, warm sterilised jam jars. If you see any air bubbles remove them. Seal and label the jars while they are still warm. Allow them to cool completely then store.
The empty vanilla pods can be chopped up and stored in caster sugar which over time infuses the sugar with vanilla flavour.
Before you start your jam, make sure all of your jars are still airtight, then wash them and set to dry. An easy way to sterilise your jam jars is wash them in your dishwasher, so they come out sterilised, hot and dry and ready to use.