How long can sandwiches keep on dry ice?

Dry ice is a solid form of carbon dioxide, and it sublimates at temperatures below 78.5°C. This makes it an excellent coolant, and it is often used to keep food and drinks cold. Sandwiches can keep for several days on dry ice, as long as they are properly packaged and stored.

Here are some tips for storing sandwiches on dry ice:

- Wrap the sandwiches in plastic wrap or foil to prevent them from drying out.

- Place the wrapped sandwiches in a cooler with a layer of dry ice on the bottom.

- Cover the sandwiches with another layer of dry ice.

- Seal the cooler tightly and store it in a cool place.

- Check the dry ice every few days and replace it as needed.

Sandwiches can also be stored on dry ice in a freezer, but it is important to make sure that the temperature is below 78.5°C.