After my colonies were robbed out last fall, I took my 10 frame deeps to the freezer for 48 hours. They have since been sitting out (under a roof), waiting to be populated again next spring. The frames are fully drawn but not entirely empty. There are some partially full cells of what might be pollen or bee bread. Also, some cells have what looks like white mold around the openings. All cells are uncapped.
I have thought that freezing would prepare them for safe use again. But now I am not so sure. If there is old resources or mold on these frames are they safe to use? Or, do they need further attention? Thanks for any insights.