How to Make Raspberry Jam

This is a very simple two-ingredient recipe for raspberry jam, and the reason it's so simple is because we'll be using jam sugar. You'll need one kilogram or two pounds of raspberries, and one kilogram or two pounds of jam sugar, and you can find this in the baking aisle. But before you even begin, you need to sterilize any jars and equipment you'll be using. Basically, that just means a good scrubbing in some very hot, soapy water. Also, you'll be drying your jars in the oven, so turn it on to 135°C, that's 275°F, or gas mark 1, and let that heat up while you wash everything. The reason you need to sterilize your jars is so that you don't open your jam six months down the line to find that it's gone all forwards-growing mold. So, remove the impurities, and your jam will be safe for a good long while before you get to enjoy it. Once you've washed and rinsed everything under hot, running water, place the jars upside down in the oven and leave them to dry there while you make your jam. As for the jar lids, follow the manufacturer's instructions, as some of them get damaged with dry heat, so you may need to boil them in water instead. Sterilizing done, there's just one last thing. Pop a few side plates into the freezer. You'll be using them to test the jam later. Get your berries into a very large pot, and then mash the raspberries up with a potato masher, or even a fork. At this stage, you can pass the puree through a sieve to remove the seeds before you carry on. Next, add the sugar and give it a quick mix. The reason this sugar is specifically for jam is that it has added pectin in it, which is what helps jam set. Now, pectin is naturally found in fruit, but having it added to the sugar means you won't be boiling your jam for hours on end, keeping a close eye on a thermometer. Turn your stove on to a low heat and stir everything until the sugar has dissolved. This takes about five minutes. Now, turn the heat up to high and bring to a boil. Make sure to keep stirring so you don't burn your jam. As soon as it starts to bubble, set a timer for four minutes. Keep stirring while it boils away, but be careful. Sometimes the bubbles spit hot jam, so don't stand right over the pot. As soon as four minutes is up, remove the pot from the heat. This is important so that it doesn't carry on cooking. Drop a spoonful of jam onto one of your frozen plates. Leave it for a few seconds and give it a nudge with a spoon or your finger. If it sort of crinkles and looks jam-like, it's ready. If it's still a bit runny and hasn't yet set, then cook the jam for another minute and test again. Next, get your jars out of the oven and place them on a kitchen towel so that they don't slip. The easiest way to fill your jars is to use a funnel. Just make sure it's heat-resistant and, again, make sure you've sterilized it. Fill the jars almost to the top and then get the lids on. Make sure you screw them on tightly. At this point, if you press down on the lid, you'll see that it bounces back. This is okay if you plan on eating your jam in the next week or so, but to keep them for longer, you want to make sure that they're sealed properly. Bring a large pot of water to the boil and place something in the pot like a trivet so that the jars don't sit directly on the bottom. You can use your jammy kitchen towel, which then also cleans it. Place the jars inside and make sure that they're completely submerged and then leave them to boil for 10 minutes. Next, carefully take them out and leave them to cool. Over the course of the next few hours, you'll hear a big pop here and there. That will be the lids getting sucked down as the vacuum is being created while the jam jars are cooling. If you press down with your finger, it shouldn't give way. And that's it! Delicious homemade raspberry jam without a thermometer in sight.