# Safe, cheap method to dissolve nitrogen in small batches of water (10l)

I am interested in creating a nitrogen infused drink. I want to be able to make small batches of my drink (its not coffee) and testing the market before having to buy expensive equipment.

I think a way to do this is to buy a strong sealable container, fill it with my beverage and add liquid nitrogen to it. I'll then seal the top and wait some time for the liquid nitrogen to infuse throughout the drink.

I will then decant from my stronger container into smaller sealed bottles for trials.

A few questions I have are these:

1. Will the liquid nitrogen evaporate immediately as I add it to the drink, being lost to the atmosphere and thus not infusing the drink at all.
2. In order to counter part 1 can I just add a lot more liquid nitrogen than would be needed to fully dissolve in the drink in the knowledge that the container can handle the pressure.
3. If a beer bottle can maintain the carbonation of a drink, can it also maintain the nitrogenation of a drink?
• So, how much liquid nitrogen and will it freeze the drink? – Solar Mike Oct 24 '18 at 13:34
• You might want to ask this on the craft brewing SE site. Beer is sometimes nitrogen infused. – Eric Shain Oct 24 '18 at 14:25
• SodaStream machines? – Carl Witthoft Oct 24 '18 at 17:53

The starting point to recognize the limits of your idea is to appreciate the concept and magnitude of the Henry's law constant for nitrogen dissolving in water.

Using this reference, you can determine that 1 kg of water will have about 0.6 milli-moles dissolved N$$_2$$ at 25 $$^o$$C and 1 bar. By comparison, using this page

you can determine that CO$$_2$$ has about 34 milli-moles dissolved per kg water for the same conditions.

Essentially then, to obtain the same degree of "fizziness" for your proposed drink compared to carbonated beverages, you will have to raise the external pressure by a factor of about 50. You could also lower the temperature, but I suspect the water would freeze before the factor of 50 is reached using temperature.

1) Some nitrogen will dissolve in the water according to Henry's law. The rest will not.

2) When this is done to increase the total pressure of nitrogen, yes. As soon as the pressure is released, the dissolved nitrogen will escape. That escaping process is the "fizziness" that occurs.

3) Yes. But the concentration of dissolved nitrogen is about a factor of 50 times less. Hence, about a factor of 50 times less "fizziness" results.

In summary, a drink with dissolved-nitrogen will be flatter and be flatter faster when compared to a carbonated drink at the same pressure.

• Craft beer (especially stouts) are sometimes “nitro”. This is nitrogen infusion. Makes for a very creamy head. – Eric Shain Oct 24 '18 at 14:24
• @EricShain As explained by this reference, the nitrogen temporarily displaces the carbon dioxide, it does not permanently replace the carbon dioxide. IOW, nitro infusion is not a process used to dissolve nitrogen in beer instead of carbon dioxide, rather it is a process to decrease the amount of carbon dioxide dissolved in the beer (and the resulting beer goes flat rather quickly after that exchange). – Jeffrey J Weimer Oct 24 '18 at 23:12
• Perhaps, but nitro beers have a very distinctive head with fine bubbles. – Eric Shain Oct 25 '18 at 1:37
• @EricShain That foam is like soap suds. It comes from sparging the gas into the beer. It is not dissolved gas as the OP wants to create. – Jeffrey J Weimer Oct 25 '18 at 3:02