Artifact amethyst that when dipped into fruit juice turns it into booze, the reverse of what usually happens.

You can dip fruit into an uncursed potion of water to squeeze its juice out and turn it into a (maybe diluted) potion of fruit juice. However, this could be abused if fruit juice is smoky.

Tourists encounter a new shop, a gift shop, on dungeon level 1, possibly built around the entrance stairs. The gift shop stocks mostly useless items like fake Amulets of Yendor, juice and candy bars at high markups, plastic figurines of low-level monsters, and T-shirts (which are much less of a big deal to the Hawaiian-shirt-wearing tourist).

Detect food sources additionally detect potions of fruit juice, and possibly potions of booze.

Addendum to the brewing patch: you can ferment/dissolve newt corpses to produce potions of gain energy, and can combine various fruits with water to produce fruit juice. Also, since booze tastes like liquid fire, fermenting a red mold corpse produces a potion of booze.

Potion of honey; nonmagical but provides a lot more nutrition than juice. Can be obtained from bees somehow, possibly by dipping royal jelly into a potion of fruit juice or potion of water.

Fruits can be applied to create potions of fruit juice.

Fruit juice turns into booze all on its own if you leave it alone for long enough.

F corpses can be dipped into potions to make different potions: juice + violet fungus = booze, juice + yellow mold = sickness, water + green mold = acid. (Note the existence of the Brewing Patch, which dissolves most F in juice to produce confusion, hallucination, booze, sleeping, and healing.)

Later suggested recipes which involve dipping a corpse in acid to dissolve it:

• Wraith corpse → potion of gain level. (Does not always succeed, to compensate for the fact that a wraith corpse doesn’t always grant a level. Maybe it even has a lower success rate than getting a level from a corpse.)
• Newt corpse → potion of gain energy.
• Floating eye corpse → potion of levitation or possibly monster detection.

Ice boxes occasionally contain potions of booze or fruit juice in addition to corpses. A proposed frequency is 1% of ice boxes, and they contain d3 of either type of potion (possibly both).

You can dip fruits (slime molds) in a potion of acid (or potion of water?) to turn it into a potion of fruit juice (consuming the fruit).