Toss diced apples in lemon juice and set aside.
In a large sauce pan, combine the sugars, corn starch, cinnamon, nutmeg and salt. Pour in the water and whisk together. Cover and heat over medium heat until boiling.
Once boiling, cook for 2 minutes stirring occasionally.
Add apples and bring back to a boil. Simmer, stirring occasionally until apples are tender (about 10-15 minutes).
Transfer to a heat proof container and let cool completely.