I don't have the raws to confirm, but there is a possibility that the name of the fruit is similar to "ringo" but is actually diffferent.
The bear was not exactly a "bear", the wolf was not exactly a "wolf", same for the bees... So, the apple might be something different too.
She often "translates" the names based on her knowledge as a reincarnated japanese girl, but most of the time she knows and uses the fantasy names she learned as a saint.
That said, this is just a wild guess.