From the Super Mario Wiki, the Mario encyclopedia
Flying Bananas are entities appearing in Donkey Kong Country: Tropical Freeze. They are distinct from regular bananas in that they are winged and much larger. They are also characterized by two beady eyes. Although Flying Bananas are introduced in Mangrove Cove, they are more prevalent in Zip-Line Shrine; after the Kongs forcefully pull an Item Handle out of the ground at the beginning of the level, a group of winged banana statues emerge, spurting several Flying Bananas which scatter in the area. They continue to appear in subsequent stages of the game.
Flying Bananas hide inside Item Containers or under Item Handles. Once uncovered, they quickly soar and start looping through the air, followed by a trail of regular bananas. Each Flying Banana holds a prize, which can be a Banana Coin or a Puzzle Piece. Before it flies away, the Kongs should collect all bananas conducted by the Flying Banana to receive the prize.
Notable is that bananas with wings had appeared in previous Donkey Kong installments, namely Donkey Kong Jungle Beat, Donkey Kong Country Returns and Donkey Kong Country Returns 3D. In the former game, bunches of bananas enclosed in winged bubbles can be seen overflying Donkey Kong and Hoofer in glacier-themed levels. In the latter two games, flying bananas, the same size as regular ones, appear in the bonus rooms of Temple Topple, Clifftop Climb, Furious Fire, and Mischievous Moles, but are also seen outside the bonus rounds in Crazy Cart and Moving Melters.