title_body: Is it possible to make nitro cold brew coffee with a siphon?
upvoted_answer: I assume that it is possible. However, what will be the benefit? This is my opinion, but... We must try to drink coffee, not generate fancy chemical experiments.
  
  Now, the objective part:
  
  Pressurizing seems quite easy in room temperature. Depressurizing is quite problematic in a siphon. So, it will be a mess when you try to collect your brewed coffee. Or, requires fancy equipment or conditions.
  
  In a siphon, you collect the brewed coffee very rapidly. However, in cold-brew methods, the aim is brewing in a very very long time to extract the floral notes. This, again, seems problematic in your proposal.
  
  The main aim of siphon: you make infusion on top for desired amount of seconds, then, rapidly filter the infused coffee to the bottom layer. If you want to make infused cold brew, the easiest method is still again, going for a french press.