Jam is something we haven't spent much time creating in our household. I'm not too fond of the idea of adding mysterious white powders to our food. I realize pectin has been used for a long, long time, but it still creeps me out. Whenever I would look it up, I would just get some generic explanation about it gelling things and being a natural bi-product of fruit. There was rarely any info on how exactly they went from the fruit to the white granules.
Well, I am now here to tell you that you needn't use the weird white granules. All you need are some apples! I still don't know how they go from fruit to powder, but I do know how you can make your own pectin all by yourselves. This has now landed our house with a nice helping of blackberry jam and very excited boys.
Pectin is a product of fruit and 100 percent natural (at least when you make it yourself). All fruits contain pectin in some degree or another and common fruits which are made into preserves often have larger quantities. The level of pectin of each particular fruit also varies from year to year depending on weather and other mysterious factors. It is generally agreed upon, however, that apples have the highest quantities and that the pectin is normally not in the highest quantities in the actual meat of the fruit. Pectin contents are often higher in the skins, seeds, cores and such. (I still don't know how they even know that!) It is also higher in fruit which is slightly under-ripe since apparently some of the pectin is lost when the sugars are converted in the ripe fruit.
To make your own pectin you basically make apple stock. Just like someone would make chicken stock, but only with apples. In our household, we make it from all the bits which won't work to make apple rings or applesauce. All the peels, cores, deformed apples, slightly murshy ones, and other odds and ends which don't dehydrate well become pectin. Making pectin also makes your house smell really, really good.
Take your undesirable apples and cut them into quarters - stem, peel, cores, and all. Generally somewhere around 7 small apples is good. More is always better. Throw them into a large stock pot with all the other inedible apple parts. Fill with enough water to cover and simmer all day. I really mean all day. Keep adding water as needed to keep them from burning, but you are going for a look like runny applesauce. It can be helpful to smash up the softer parts with the spoon as you stew them all.
When you have runny applesauce stuff, you now need to strain out all the inedible bits. All you really want is the liquid. Line a strainer with an old T-shirt and dump in apple glop in parts into the shirt. Lift all the corners of the shirt up and squeeze the liquid out into a bowl. The apple goo can be composted (the T-shirt we just throw away because I can never get it clean again). Once it is all strained, return the liquid to the stock pot. Turn the heat up to high and boil the snot out of it. Be sure to stir constantly. The liquid will get really, really thick and can easily burn. This is your pectin. When the pectin is the consistency of syrup, it is done. Add about 1 cup of pectin for every quart of berries to achieve jam the consistency of store bought. Always do a gel test to make sure your jam will "jam" and add more as necessary.
As an added benefit, once the liquid is strained (but not boiled) it can be frozen for later use. You only need to boil the liquid down for about 7 to 10 minutes, so freezing gives you quick pectin.