How is powdered lemonade made?

Question

like how do they make the powder?

Answer 1

This isn't exactly what you're looking for, but the primary ingredient in most powdered citrus flavored beverages is just citric acid and sugar, which can be delivered in powdered (non liquid or dehyrdrated) form.  When you return water to the product, you're rehydrating the product to make "lemonade."

If you read the Wiki page on citric acid, you'll learn how it's extracted and produced.  It has many uses from household, to cosmetic, to food preservation, flavoring, and enhancement.