I love making jam. It's delicious, yes, but there is something very satisfying in a pot of homemade jam. Made by me. For you. Yum. If you can find fruit for a good price to buy in quantities, or if you grow fruit or wild harvest berries (free!), you can make up decent amounts of jam quite easily for a fairly low cost.
Here is the easiest way I have yet found to can jam. The Aga. Okay, I will have to explain that for you. I will also include alternate directions for those of you who do not own such a wonderful thing.
An Aga is a huge cast iron oven. It is on all the time. I'm in England, now, remember? The Aga both heats and dries the house, which is a very good thing here. There are different models you can buy. This one is a four door oven. Top left is simmering, bottom left is warming, top right is roasting, and bottom right is baking. There are also two stone plates on the top of the Aga oven, the left for boiling and the right for simmering. For jam, I use the simmering oven, which is approximately 225-250 F, or 110-130 C. I don't bother with a shelf and just place the jam on the floor. (The top of each oven is hotter than the bottom of each oven. Bread, for example, bakes for 10 minutes on the floor of the roasting oven and then 25 minutes in the middle of the baking oven.)
England sells jam sugar. Brilliant! The sugar is already measured and mixed with the right amount of pectin for making jam. Of course, this doesn't allow for specific needs on finicky recipes, but it does take another step out of making most regular household jams. Jamming is pretty darn easy! Here's what you will need.
- washed red currants (strawberries, raspberries, blackberries, blackcurrants, gooseberries, apples, rhubarb, peaches...)
- jam sugar
- a leetle bit of unsalted butter
- glass canning/jam jars with lids etc.
- a large pot with tall sides to catch popping and splashing jam
- a long handled spoon
- a potato masher
- a ladle
- a clean dry cloth
- kitchen scales
Weigh out the fruit. Dump into the large pot. Weigh out the jam sugar to the same weight as the fruit. Dump that in the pot, too.
Put the pot on the simmering plate, ie. over a low-medium heat. Stir occasionally. Let the fruit cook and the sugar dissolve. This only takes a few minutes so don't go walkabouts.
Once the sugar is fully dissolved, move the pot over to the boiling plate, ie. over a high heat. Bring the jam to a proper boil, and then move back over to the simmering plate where it will keep simmering steadily. For those of you not using an Aga, just keep an eye on the stuff. The goal is to dissolve the sugar, then properly boil, then keep at a steady rolling simmer for a little bit.
Now, use the potato masher. You don't have to. It's totally up to your discretion. Most berries don't need to be mashed but currants and gooseberries have a slightly tougher skin. Use the potato masher to smash up and burst the red currants a bit further so the texture of the jam is a bit nicer. I still leave a few lumps in, though. I don't like my jam perfectly smooth.
Here is where you add your butter. It's approximately 1 tsp unsalted butter per 4 cups of jam. I eyeball it. A little variation doesn't matter much and you can make 15 cups of jam in a batch this way, so just add what you think is about right. The butter helps to reduce the foaming that appears on top of the jam. If you go dairy-free, replacing the butter with a little coconut oil is fine. (Not vegetable ghee, though.)
Now, time the jam at this steady, low-rolling simmer for about 10-15 minutes. Stir it occasionally. You want the jam to start jelling up a bit now. You need to look for what they call "sheeting" off the back of a spoon. Basically, when it looks like warmed jam? a bit thick and goopy on the back of a spoon? or you can take a spoonful of the hot jam, drop it onto a cool plate, and watch it firm up into a normal jam-like texture? That's when it's ready. Told you. Not that hard.
Take the jam off the heat. Carefully, ladle hot jam into your prepped and ready hot glass jars. Put the lids on right away.
Here you have some options.
Do you have a lot of jam that you want to be shelf stable? Use self-sealing lids, the kind sold with jam jars or canning jars for this purpose.
Do you want to finish up the jam in the oven? Pop the filled jars back into the Aga simmering oven, or into a regular baking oven at the same temperature, for about 45 minutes. Then remove, set jars onto a wooden or cloth-covered surface (so the bottoms don't cool too quickly and crack), and leave until fully cool.
Do you want to finish up the jam in a standard canning water bath? Go for it. Process 5 minutes at full boil submerged in a pot of water, the usual way. Then remove, set jars onto a wooden or cloth-covered surface (so the bottoms don't cool too quickly and crack), and leave until fully cool.
Did you make a small batch, perhaps just a jar or two, of jam, as a first-time experiment or because you didn't have much fruit to use up? There is no need to specially seal the lids. Just pop the lids on to a firm finger-touch, leave to fully cool, and then store in the fridge.
Finally, do label your jars. These aren't cool yet so they've not been labelled. I confess that, as usual, I am not bothered enough to print out proper labels that look really good (and cost more). Unless the jar is a gift and deserves a bit of swanking up, I do my usual duct tape and permanent marker labels. Include on your label the type of jam and the date made.
What flavor of jam will you make next?