Actually it is a very simple process. We use a ten quart stock pot and a six-quart slo-cooker. Peel and core your apples in batch size amounts. Janet does this and tosses the chunks of apple into a bowl if ice-water that has 'fruit-fresh' added. When she fills the bowl with roughly 10 quarts (plus a bit) she turns them over to me. I fill the stock pot to the top with the chunk apples, add about a cup of Apple juice and a couple of overflowing tablespoons of lemon juice. I Heat the apples to a boil stirring constantly to avoid scorching. Cook until the chunks have softened considerable. They cook-down a lot as they soften!
At this point we use two methods depending on the final product.
1. We like very coarse grind Apple Sauce A LOT!. If this batch is to be AppleSauce, we lower the heat and add two to three cups of sugar (taste test a lot) and a tablespoon of Cinnamon and half-teaspoon of ground clove. Bring it back to the simmering point and then run a hand mixer thru the apples until they are "sauced" to meet your needs! A few minutes on high-speed near the end of the process seems to really get the apples "sauced". Then Bottle and seal using whatever process you wish. ! Makes a bit more than a gallon depending on the size of the bottles you use.
2. If Apple Butter is your final product. After bringing the apples to a boil and cooking til soft (about 10 minutes) over a medium-high heat, Use a Foley grinder (or a food processor) (We have a 3.5 quart Foley hand crank food mill that works great) to strain the apples into your crock-pot or slow-cooker. Set the cooker on high for the first two or three hours...just enough to bring the apples to a simmer around the edge of the cooker. Add Sugar to taste, and Cinnamon and ground clove (if you like Clove!) a bit more than you did with the AppleSauce. We also add a tablespoon of lemon juice to help thicken up the mixture as it cooks. After the first few hours you can turn down the slow cooker to lo and let it go for ten-twelve hours, or until the consistency reaches the point you like the most. We found that some apple species took much longer to thicken and darken than others.
When close to ready, heat it back up on high to help the 'Butter' to seal the jars when you fill them. Process using whatever style you wish...Pressure canners scare the hell out of me, so we either water-bath the jars or refrigerate them for short storage.
To repeat.. Sweetening and Spice intensity is a matter of personal tase. Some would prefer not to add any sugar at all..others like more or less of the spices added. Since the apples cook for a considerable length of time it is pretty easy to adjust the sweet and spice level slowly as you cook. Remember though that the sugar does seem to aid the thickening process.