When it comes to serving cocktails on tap, you have the option to use either nitrogen (N2) or carbon dioxide (CO2) gas. The choice between the two gases depends on the specific cocktail ingredients and the desired serving style.
1. Nitrogen (N2):
Nitrogen gas is commonly used for serving still or “nitro” cocktails on tap. Nitro cocktails are known for their smooth and creamy texture, similar to that of a Guinness beer. This gas provides a velvety mouthfeel and enhances the overall drinking experience.
To serve nitro cocktails, you'll need a nitrogen tank and regulator. The nitrogen tank will contain compressed nitrogen gas, and the regulator will control the flow of gas into the keg. The regulator should be set to a specific pressure suitable for the cocktail being served. It's important to note that nitrogen does not dissolve into liquids as easily as carbon dioxide.
2. Carbon Dioxide (CO2):
Carbon dioxide gas is the more commonly used gas for carbonating beverages, including cocktails. It creates the effervescence and bubbles that we associate with carbonated drinks. CO2 is suitable for cocktails that benefit from a fizzy and refreshing character.
To serve carbonated cocktails, you'll need a carbon dioxide tank and regulator. The carbon dioxide tank contains compressed CO2 gas, and the regulator controls the pressure and flow of gas into the keg. It's important to set the CO2 pressure to an appropriate level, as too much pressure can over-carbonate the cocktail and result in a foamy mess when dispensed.
It's worth noting that some cocktails may benefit from a combination of both nitrogen and carbon dioxide. For instance, a cocktail with a creamy base that also requires carbonation can be served using a blend of both gases. In such cases, a dual-gas regulator is used to control the flow of both nitrogen and carbon dioxide into the keg.
When deciding between nitrogen and carbon dioxide, consider the specific characteristics you want to achieve in your cocktails. Nitrogen is ideal for creating a smooth, creamy texture, while carbon dioxide adds effervescence and bubbles. Experimentation and personal preference play a significant role in determining which gas to use for each cocktail.
In my experience as a sommelier and brewer, I have used both nitrogen and carbon dioxide for serving cocktails on tap. Nitrogen works exceptionally well for cocktails with cream or dairy components, such as espresso martinis or creamy coffee cocktails. On the other hand, carbon dioxide is perfect for classic carbonated cocktails like mojitos or margaritas.
Ultimately, the choice of gas depends on the desired mouthfeel, texture, and carbonation level of your cocktails. It's always fun to experiment and discover the perfect gas combination for each unique cocktail creation.