http://pickyourown.org/applepicking.htm has wonderful tips and how to's for canning all sorts of things. They also have links to farms in your area to help you find places to go for you-pick. They are a great resource and I have used their apple butter recipe for years with a few "tweaks".  I only use 1/2 the brown sugar called for, and for a full size recipe I add 3 drops DoTerra Wild Orange essential oil, and  2 drops of DoTerra Clove oil.  This is not enough to change the PH of the apple butter or make the canning process unsafe. It is enough, however, to add a little zing of citrus flavor as well as the immune boosting benefit of the essential oil. During the winter, when the vast majority of our apple butter is consumed, we need all the immune boosting we can get!  
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