I think it would be a shame if the title was lost in the mix, but as stated by the OP apples are clearly not a trope in and of them selves.
A "fruit as symbolism" index (something like Panthera Awesome
) could be a good idea, and might cut down on not-a-trope examples. We could merge Strawberry Shorthand
into this (strawberries might be used enough to merit there own trope but a broad trope like that encourages overuse). Then you have pomegranates, etc. And even a section for made up fruits (like Devil Fruit from One Piece).
I think this could get tricky with fruits that mean different things to different cultures. Peaches, for instance, are related to immortality in Chinese (and derivative) myths where as American culture uses them frequently as shorthand for sex/young women (to the point where people were unwilling to accept that the Presidents of the United States song 'Peaches' was actually about... well, eating peaches).
Specifically regarding apples, (I can't remember where or under what context I read about this so chalk it up to speculation on my part) they were very important to several ancient cultures and as a result were used as a sort of default for depicting magic fruit. Ie, they were used in myths when the goal was to not add the symbolism of the fruit in question to the story one was telling. As an example, neither the fruit of the Tree of Knowledge nor the Tree of Life (which may be the same tree) is explicitly an apple in the Bible or Talmudic scholarship... depicting as such came about much later (when artists started drawing it).
Whatever the final solution here, it should be explicitly stated not to post Erotic Eating
examples on any fruit related page (all fruit and probably anything else can be eaten in an erotic fashion...)
Final thought/question: Is a golden apple different from a regular apple? I mean, other than the cosmetic difference, is it tropeworthy when a magical fruit is golden? The fruit of Tree of Knowledge wasn't golden but it was otherwise magic (sort of)? Does the myth of Discord change at all if she had just written "To the fairest..." on a regular apple?