Lets refer to the food techy here for a minute. Setting point is all about the pectin to fruit to sugar ratio found in jams and preserves. Pectin is a naturally occurring gum that is present in various levels in most fruit. Some fruits are higher in pectin than others. Dont panic, you dont need to know your pectin levels to make jam as most recipes will assist you with this by adding fruits higher in pectin if the base fruit is lower. Often lemon juice (high in pectin) is added to jams to assist with the setting point. Whats important is not to be too worried about this if you are just starting out with making jams and preserves. If its overset, so what, usually the flavour is wonderful and caramelised. If its underset, bung it in the fridge to harden up and again the flavour will be wonderful! Just have a go. Try some simple jams like apricot or strawberry, because if all else fails, they make wonderful glazes for fruit flans and other tarts!
I use several methods to check for the setting of my jams, marmalades and conserves.
Firstly the old plate in the freezer check.
Place a small plate in the freezer. I use a lighter coloured or white plate, so that you can see the liquid. Also don’t use grandmas Royal Doulton that she gifted you, as invariably you will forget to take it back out of the freezer and you will find it months later craked but supporting the 2kgs of frozen sausages. Once the plate is cold I place a small dollop of the jam on the plate and push my finger through it. Keep testing and once the liquid starts to wrinkle, its ready!
It will start to thicken and the bubbles will be “bloppy”…. (Sorry no other word for it) and when you lift your wooden spoon out you will notice that the drops are “elongated” and slower to drop.
I place this in my mix and check the temperature. Most jams will set at 104- 105 degrees. However I have to say that I have found the plate in the freezer trick works better than the thermometer. Sometimes I have over set the jam when using the thermometer and I also prefer a lighter set to my jams anyway. This allows me to store them in the fridge which is preferable in the Australian climate despite the amount of sugar preservative we use.
Just give them all a go and you will start to be familiar with your mixtures. Also the more you make of the one recipe the more you will be familiar with its setting point. Nothing is more rewarding than making jam!