I personally have never had an issue but DH has. After he processes I rinse the cavity real good and if he left the lungs in I just slide my fingers along the rib cage and pluck them out. It's probably the cold water that makes it easier but having skinny fingers helps too. I always part out our birds(drumstick in one bag, wings in another,etc.) before freezing so I know for sure all the organs are out. It's easier for my family to not remember the bird when theyre pieced out like that rather than freezing a whole bird.
