Insectivorous bats have the same sweet taste receptors as fruit bats, but have lost the ability to actually taste sweet food
Source:
https://www.newscientist.com/article/2266718-bats-that-eat-insects-should-be-able-to-taste-sweet-food-but-cant/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home