Wash the green apples thoroughly under running water to remove any dirt or residue. If desired, you can peel the apples, but leaving the skin on adds extra nutrients and fiber to the juice.

Core the apples and chop them into smaller pieces. Removing the core helps prevent any seeds from ending up in your juice.

Place the chopped apples into a juicer. If you don't have a juicer, you can use a blender or food processor instead. Blend the apples until they turn into a smooth puree.

If you prefer a smoother juice without pulp, you can strain the puree through a fine-mesh sieve or cheesecloth to remove any solids. Press down on the pulp to extract as much juice as possible.

If you want to enhance the tartness of the juice, you can add a tablespoon or two of fresh lemon juice. This step is optional but can add a nice zing to the flavor.

Taste the green apple juice and adjust the sweetness according to your preference. You can add a natural sweetener like honey, agave syrup, or maple syrup if desired. Stir well to ensure the sweetener is fully dissolved.

Transfer the green apple juice to a pitcher and refrigerate it for at least 30 minutes to chill. When ready to serve, pour the juice into glasses filled with ice cubes for a refreshing drink.