An unopened bottle of apple juice found by Dave Strider in his closet.
It was quite a nice surprise. Dave intended to enjoy this juice, but was too freaked out by images of a monster Howie Mandel replacing it with urine, thanks to John (read: trolling) him about people putting piss into apple juice bottles in factories.
It was later accidentally expelled from his Sylladex when he captchalogued his Ninja Sword, spilling on his precious turntables as well as his copies of the Sburb Beta (it looked like piss, and Dave he'd never let anything even remotely resembling piss touch his beloved turntables).
Act 4 shows him drinking another bottle of apple juice causing him to need to pee. He considers using the empty apple juice bottle and sending the pee-filled bottle's card code to John so he would drink the pee. But he later dismissed the idea because it was boring.
In, Dave wishes that he had apple juice.
In part 3 of Openbound, Dave can chat with Rose, who is trying to use bottles and old-fashioned alchemy in an attempt to make unspecified tasty beverages. Dave asks her if she's making apple juice, and she says she'll see what she can do. However, , it turns out that the only thing Rose has been able to make is booze. Dave expresses frustration with her inability to alchemize apple juice, while Rose explains that an apple is as closed to being a noshushnally irredushible object as it gets.