Honey DNA is used to identify the pollinating habits of bee populations. The concept of adapting DNA analytical techniques to honey samples was pioneered by Noah Wilson-Rich, co-founder and chief scientific officer of The Best Bees Company. This link to a recent National Geographic story gives a nice overview of the concept.
Btw, the photo accompanying this post is that of a honey bee queen (blue dot) surrounded by her attendants. It was taken in one of our observation hives in summer 2017 during a Phase 1 DARPA grant.