Mischna zu Bamidbar 18:12

From where do we derive that first-fruits must precede terumah, seeing that this one is called “terumah” and “the first” and the other is [also] called “terumah” and “the first”? Rather first-fruits take precedence since they are the first fruits of all produce. And terumah comes before the first tithe also because it is called “first.” And first tithe [precedes second tithe,] because it includes that which is called “first.”

One must not make dates into honey, apples into wine, winter-grapes into vinegar, or change any other kind of fruit that is terumah or second tithe from their natural state, except olives and grapes. One does not receive forty lashes on account of orlah except with that which comes from olives and grapes. Liquids cannot be brought as first fruits, except with that which comes from olives and grapes. And no fruit juice is susceptible to uncleanness as liquids except with that which comes from olives and grapes. And nothing [that is derived from fruit] can be offered on the altar except with that which comes from olives and grapes.