US FDA Food Labeling Regulations (21 CFR Part 101) 101.30: Percentage juice declaration for beverages that contain fruit or vegetable juice, 'contains X% juice', the 'flavored' naming for beverages with less than 100 percent juice, and reconstituted and concentrated juice rules (101.30)

What does 101.30 require?

A beverage that purports to contain fruit or vegetable juice (by name, flavor or imagery) must declare the total percentage of juice on the information panel near the top with 'Contains X% juice' or 'X% juice' in a type size at least as large as the ingredient statement minimum, calculated on a single-strength basis using the Brix values in 101.30(h) for reconstituted juices. A beverage containing less than 100 percent juice whose name includes a juice name must be labeled as a 'juice drink', 'juice beverage', 'juice cocktail' or with 'flavored' in the name, and 100 percent juice made from concentrate must say 'from concentrate' or 'reconstituted' with the name. Diluted multiple-juice beverages that name only some of the juices must state that the named juice is a flavor or declare its percentage.