Making jam and setting point...

[didds]

So we all know about saucers in the fridge, and testing a jam for setting by a small dribble left to cool on the aucer and then pushed with a finger to wrinkle.

My problem is my jam NEVER wrinkles (ditto marmalade).

So I basically have a good rolling boil for ten minutes or so then pot up and hope. Mostly sets, sometimes never and i end up with a runny compote (which still works of course but needs to be kept in the fridge I always presume )

Is there some other method that is somewhat more fool proof that the wizardry and guesswork with alleged wrinkling?

didds

[Alaric]

Is there some other method that is somewhat more fool proof that the wizardry and guesswork with alleged wrinkling?

Jam thermometers ?

[didds]

Is there some other method that is somewhat more fool proof that the wizardry and guesswork with alleged wrinkling?

Jam thermometers ?

aha! I never knew they existed! winner winner chicken dinner!

[Nimrod103]

You can add pectin which you can buy in a supermarket.
I don’t use a thermometer. I think 10 minutes rolling boil is not enough. I go for 15 minutes minimum and usually it will wrinkle on a cold plate. Some jams set more easily than others. Gooseberry sets very well and the setting point is just about when the jam turns very slightly reddy brown, which I presume to be when the sugar begins to caramelise.
Strawberry is very difficult to get to set, and raspberry not much better. I would add pectin.
Blackcurrant and redcurrant jelly sets very easily.

[Urbandreamer]

I have a thermometer that I don't use, because I stopped making jam.

I bought it because I was getting either jam you could pour or jam you could carve. I really recommend them to anyone having difficulties. As said, pectin is important. It's just not usually an issue with most jams. I would advise thinking about it if making rhubarb jam, as rhubarb doesn't naturally have any. So consider it if not following a recipe. If you find it difficult to buy, see if you can add citrus fruits or apple. Failing than save pips from them to cook with and remove from the final product.

[johnstevens77]

Use lemon juice to activate the natural pectin in the fruit. For strawberries, I marinate them whole overnight with lemon juice and the sugar, no added water. I have already made blackberry, raspberry and blackcurrant jellies this year, no prblems. Your problem might be the power of your cooker, it helps if you can boil it really hard.
john