Minneapolis has a lot of O&D. It's home to 20 fortune 500 companies and the state of Minnesota is one of the best economies in the country. I read somewhere that it is by far Deltas most profitable hub on a per passenger basis and Richard Anderson calls it one of the best airports in the world to operate out of. I wouldn't lose too much sleep about MSP going away as a Delta hub/base.

MSP is very safe. The only base in the current system at risk is CVG.

Posted in the wrong thread.

That is why it makes me worry.

How long does it need to keep?

I'd think if it was hard frozen before and kept in anything even semi insulated it would be fine for a while. Worst case ice it down at the hotel on the overnight. Unless it has to be lugged around until day 11 of a 12 day or something, I can't imagine dry ice would be even remotely required.

I bring frozen items often. They will keep at least 48 hours in a cooler with no problems.

Tomato sauce can't be refrozen, it starts to taste funny. It must stay frozen until ready to be used.

Also many hotels have fridges in the room or another one you can store stuff in. Also if the hotel does not have one you could store it in the ops room fridge. I would guess all our ops rooms have fridges. If you pack a lunch pail and freezer packs you would be ok. You can usually find a place to store them and re freeze them.
Lastly I have heard of flight attendants using head ache bags and filling them with ice every morning and night. They say those work well.