All pure fruit juices are considered kosher except for which type?

Grape juice is often considered the exception among pure fruit juices when discussing kosher status due to its significance in Jewish rituals and religious observance, particularly in the context of wine used for blessings and ceremonies. The production of grape juice requires particular attention to ensure that it meets specific rabbinical standards. If the grape juice is not produced under strict rabbinical supervision, it may not be deemed kosher, unlike other fruit juices such as orange juice, apple juice, and cranberry juice, which generally do not have such strict requirements. Therefore, the unique requirements around grape juice production and its relationship to Jewish tradition lead to its differentiation from other fruit juices in matters of kosher status.