In a large bowl, toss the diced apples with the lemon juice immediately to prevent the apples from browning.
Add the corn, mayonnaise, salt, ground black pepper, and parsley. Toss well to coat.
Transfer to food-safe container and refrigerate for a minimum of 2 hours before serving.
For this recipe, you can use canned corn that has been well drained. Or, you can use fresh corn that has been removed from the cob, cooked, then cooled. Alternatively, you can use bagged frozen corn that has been blanched in salted boiling water for a few minutes, drained and cooled.