I could try and pretend that there was some great Heston Blumenthal moment here in my decision to combine strawberry and raspberry into one jam rather than keeping them segregated as seems to be the custom. I’ll be quite honest, the reasoning behind this recipe was because I hate decision making and for so many recipes I labour long and hard over whether or not to use strawberry jam (which just works better with certain flavours) or raspberry jam (which is – or was – my favourite flavour jam). What I have discovered is that no one should ever eat them separately again. Ever. In my opinion, this is the best jam I’ve ever tasted (and I’m not just saying that because I made it!) It really is the perfect balance and for anyone scared of making jams, this is a great place to start.
- 14 ounces / 400g strawberries, quartered
- 14 ounces / 400g raspberries
- 1lb 12 ounces / 800g jam sugar
Sterilize your jam jars as per instructions (I always follow these Kilner instructions ).
Place your berries and sugar into a large preserving pan or saucepan (be aware that the mixture does bubble up considerably so don’t be fooled into thinking that just because the ingredients will fit into a smaller pan that it will suffice!)
Give a good stir until everything is well combined (your berries … although nerd alert … they’re not really berries … will already be starting to break down).
Put the pan on a low-medium light and heat slowly. You can shake the pan gently every now and again, but do not stir.
Once the sugar has dissolved and the mixture is turning syrupy you can turn the heat up to high at which point it will likely start to bubble. Keep an eye on it so that it doesn’t bubble over.
Using a sugar thermometer to check the temperature, keep heating your jam until it reaches setting point (105°C / 221°F).
Remove from the heat and using a jam funnel decant it into your sterilized jars and seal and leave to cool (preferably overnight). Make sure you skim off any scum there might be on the surface before putting it into jars as this will make it taste slightly bitter.
The unopened jars will keep for a good few months but once opened the jam should be kept refrigerated and eating within 4 weeks.
You may also, as a precaution, like to put an upturned saucer into the freezer and when the jam reaches setting point, carefully dollop a spoonful onto the back of the cold saucer and leave it for a minute or so to cool. Then press it gently with the tip of your finger and there should be a skin that wrinkles. This means your jam has set. If not, continue to heat for a few more minutes and try again. Don’t be fooled into thinking that just because your jam is still quite syrupy that it hasn’t set – it will go more solid while cooling in the jars.
Jam sugar which can readily be found in most grocery stores and supermarkets contain the right amount of pectin which is present in some fruits but not all. Pectin is what helps the jams or jellies to set. For fruits such as apples and citrus which are already high in pectin you don’t need jam sugar but use preserving sugar instead. Apples are a good source of pectin which is why you often find them combined with other fruits. Strawberries and raspberries being low in pectin therefore need the pectin-enriched jam sugar.