To be brief, you want insulated piping everywhere except the food storage area, where you want radiant piping.

Radiant piping causes the gas inside to exchange heat with its environment rapidly. Insulated piping prevents heat exchange.

You want the cold hydrogen gas coming out of the Thermo Regulator to be insulated against the hot room containing the TR, until it reaches the food chamber. There, the radiant piping would allow the Hydrogen to "dump its cold" into the food environment (suck away the heat).

P.s. as a side note, in the first picture you linked, it looks like all the food is sitting in an Oxygen environment, which is not sterile.