I have canned applesauce ever since I was a little girl. This year, I went to North Carolina for a week to visit a friend and make applesauce since apples don't grow here in Florida. I made 171 quarts of applesauce and 38 quarts of apple butter!
This is how we do it:
1. Wash the apples
2. Slice the apples. If you have a lot of apples to cut, something like this: http://www.applesource.com/peeler.html
will save you a tremendous amount of time. The one I have, you can move the peeler piece out of the way so it does not peel the apples. It may or may not be necessary to peel the apples, as you will see. If the apples are red, it is nice to not have to peel them because it will give the applesauce a nice pink color.
3. Put a small amount of water into a pan (like just enough to coat the bottom), stuff the pan full of cut apples, cover, and cook over medium-high heat until the apples are quite soft.
4. You then have to process the cooked apples through a food mill. I have this one: http://www.backtobasicsproducts.com/...products_id=49
This allows you to make a lot at one time quite easily. You can also use something like this: http://www.applesource.com/foodmill.html
although I have never personally used one. Either way, this machine will separate the unedible bits and send out the applesauce!
5. I put the applesauce in a very large bowl, that holds 32 cups. When it is nearly full, I add 3/4 cup of sugar and stir it in well. (I have never used maple syrup for sweetner, but don't see why it would be a problem. I think you could just add it until it was as sweet as you wanted. I'd start with 1/4 cup at a time, stir it in, taste, etc, for the first batch, then add the same amount to each batch after that. You don't HAVE to add sweetner. I made some without for my diabetic grandfather).
6. Put into prewashed jars (I run them through the dishwasher), and put the lids on and screw on the rings.
7. I have always processed my applesauce in a water bath canner: http://www.backtobasicsproducts.com/...products_id=85
You can get one of these at Walmart for about $18. However, this year, we could not use this because my friend's mother had a glass top stove. So we used a very big pot, and put the jar rings on the bottom of the pot and balanced a jar on top of each ring. This caused rust marks on the bottom of the pot, so you might want to use another method. The jars need to be elevated off the bottom of the pan in order to allow the water to circulate all the way around them. Fill with water so that the water comes just to the bottom of the neck of the jars. Bring to a boil and after it starts to boil, time for 20 minutes. Remove jars from the water. It is very helpful to have one or two of these: http://www.backtobasicsproducts.com/...products_id=89
for this purpose (it is upside down in the picture. The red part is the part that actually goes around the jar). It is not necessary to use a pressure canner, although you can if you want. I have never done that, so could not tell you what pressure you need to bring it to or how long it needs to be at pressure.
I hope everything goes well. Once you eat homemade applesauce, you just can't eat the stuff from the store! Feel free to PM me or e-mail me if you have any questions!
ETA: I get about 18 quarts of applesauce from 1 bushel of apples.