When I canned apples and apple pie filling this summer, I froze the apple peels and cores. When fall came and my freezer was so full that going shopping meant a stressful session of trying to fit new things into not enough space, I pulled out all the quart-size bags I could find and made apple juice.
The juice will be used to make jelly, not for drinking; I suppose that if I added sugar it would be drinkable but I haven't tried it. We don't eat a lot of jelly on toast; most of the apple jelly ends up in sauces and glazes for chicken, pork, and such. Our favorite use is in dump chicken; the original recipe called for peach or apricot jam, but it is delicious using apple jelly instead.
I dumped four quart-size freezer bags of apple cores and peels into a stockpot and added three quarts of water, then let it simmer for an hour or two. It turned out to be a beautiful fall day, on the warm side, and the house got pretty hot. When it had simmered long enough, I let it cool for awhile, then strained the solids out with a muslin jelly bag.
I then simmered the juice awhile longer, since it tasted kind of thin. I ran the juice through the jelly bag a second time, and ended up with almost two quarts of juice, and a half-cupful of what looked like thick applesauce. I added the applesauce to the goats' feed the next morning, and gave the cooked peels/cores to the chickens.
As you can see, these two jars are different colors. The pink juice was made a week earlier, using the same method, from apples from our own trees. The juice that looks like commercial apple juice was made from a combination of our apples and the apples from my neighbor's trees. I need to run the pink juice through the jelly bag again to remove the sediment before I make jelly from it. The two batches yielded almost two quarts of juice each, so I ended up with almost four quarts of juice to use in making jelly. All of this came from just peels and cores that most people throw away.
For another use for apple peels, go to Dehydrate 2 Store and choose the video "Apples, Apples, Apples". Tammy throws out the cores though.
Here is a recipe for making apple jelly without using pectin.