It's demonstrably true that there was a significant period of introduction of new foodstuffs from the Americas into Eurasia in the wake of Columbus, in a phenom

It's demonstrably true that there was a significant period of introduction of new foodstuffs from the Americas into Eurasia in the wake of Columbus, in a phenomenon known as the Columbian Exchange: https://en.wikipedia.org/wiki/Columbian_exchange https://en.wikipedia.org/wiki/Columbian_exchange. Since custard apples are native to Central America, it's the natural hypothesis.