I've heard this alot since I started making all three this summer. People are curious to know what makes a fruit spread a jam and how is that different from a jelly or a fruit butter. I didn't know the answer to this question until June.
When I was younger and living with my parents, I used to go and pick wild berries with my father. We would then bring them home and he would "juice" them. This entailed boiling them in just enough water to cover them and then straining the juice through cheeseclothe or a pillowcase. The pulp was discarded and my mother would then take the juice and turn it into jelly. So, I knew what jelly was. And that was essentially all we used in our house for a long time.
One day I asked my mother what the difference between jam and jelly. She told me that jam have the seeds left in it. I thought that was a terrible idea. Who on earth would want to pick all those raspberry seeds out of their teeth?
Many years later, I discovered the wonders of strawberry jam and learned that the whole fruit was included. What a happy development for me! So, when I started canning jellies this summer I decided to try my hand at making apricot jam as well.
All the recipes I see call for fruit to be cut very finely for jams. I do not believe in this. I wanted big hunk of fruit to survive in my jams. So, I cut fruit accordingly. I soon discovered that fruit floats to the top of the jars.... a bummer to be sure unless you want to constantly stir your jam before spreading it.
I went on making jam and jelly until.... I found my old Blue Ball Book of Preserving hanging about in my kitchen. Hmmmmmmm.... I flipped through to see what their jelly and jam recipes said. Low and behold, I stumbled across a recipe for Apricot Butter. Curious I read on to discover that fruit butter does NOT contain any dairy product. Fruit butters are merely fruit, skinned and pitted and food processed to a smooth pulp and then cooked down to a thick state.
And so I made apricot and peach butter as well as the traditional apple and pear butters.
There you have it. Jelly is made from fruit juice, jam from cut up bits of fruit and fruit butter is processed fruit pulp that has been thickened.