In a large bowl, toss the apples with the lemon juice; put aside. In Dutch oven (large kettle works) over medium heat, combine sugar, cornstarch, cinnamon, salt and nutmeg. Add water; bring to a boil. Boil for 2 minutes, stirring constantly. Add apples; return to boil. Lower the temperature; cover and simmer until apples are tender, about 6 to 8 minutes. Cool for 30 minutes. Pour into freezer containers leaving ½ inch headspace. Cool to room temperature no more than 1h30. Seal and freeze; keep for up to 12 months. Yield: 5 ½ pints (enough for about five 9-inch pies).
Alright, here are my tips. Instead of quart jars, I use gallon-sized freezer bags. Let the filling cool a little before filling the bags (one liter per bag), then flatten the bag to freeze it. This way you can stack the filler “boards” in your freezer and slide one out as needed. Less space needed and the defrosting time is shorter. After thawing, I heat mine on the stovetop or in the microwave before putting it in my pie crust, and sprinkle it with butter before sealing the top crust.
Along the same lines, you can stack and freeze your pie crusts. Roll them into your 8 or 9 inch circles between wax paper and stack them together in one of those two gallon freezer bags. Thaw in the refrigerator overnight before use!
Enjoy !