“Now, let’s try it with liquid nitrogen…”.
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Though I only do it only occasionally, over the years I have successfully chilled cans and bottles of soda with immersion in salted ice/water. I’ve done it with the can/bottle standing upright in a cylindrical container, whose diameter is about twice that of the subject can/bottle. I surround it with ice, salt and scant water to completely surround the can/bottle. It only takes occasional rotation and 2 - 3 minutes to chill the can/bottle to a desirable (I haven’t been sufficiently OCD to check the temp) temperature. Besides, my supermarket is usually out of stock of liquid nitrogen.
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Besides, liquid nitrogen doesn’t work that well. There are two main reasons for this. First, liquid nitrogen has a specific heat capacity much less than water, which is exceptionally high. This means it takes a lot of converting liquid nitrogen into the gas phase to cool a given amount of water. Second, the moment a warm object is immersed in liquid nitrogen, gaseous nitrogen bubbles are formed in great profusion on its surface. These serve to insulate the object from the liquid nitrogen by a phenomenon like the leidenfrost effect.
Circulating liquid water in direct contact with the object extracts heat from it much more efficiently even though the temperature difference isn’t anywhere as large.
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I wish he had tried putting some salt in the cooling machine - and measured the impact. I know, it might damage the device.
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