How can/do you freeze food with dry ice?

Question

Hello,

my science teacher showed us how he froze marshmallows, icecream,vegetables, etc by quickly dipping them into a container with water and dry ice.

I bought dry ice, put it in a container with water, and put a Choco Puff in for 5 minutes, yet it didn t freeze at all.

I am very dissapointed.

Am i doing something wrong?

Please tell me and give some advices!

Help would be extremely appreciated.

Thanks in advance!

~

Answer 1

add lots of salt.  Try again.

Answer 2

CO2 sublibates at about -70F. I don't think that's cold enough to freeze a coco puff. I'm pretty sure it would just cause it to get soaked with cold water (assuming ther water wasn't solid ice). Try using liquid N2. It'll work much better (that's probably what your teacher was using).