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Dissolved nitrogen in a liquid medium is measured using the same procedure as the CO₂ determination, i.e., using heat conductivity.

CO₂ is employed as a purge gas in the beverage industry. Therefore, in order to measure nitrogen, the change in thermal activity and CO₂ and N₂ is used. The thermal conductivity is determined in a small measurement chamber, which in turn is separated from the material being measured by a semipermeable membrane. Diffusion through the membrane changes the thermal conductivity in the measurement chamber.

The gas volume in the measurement chamber is fully replaced in cycles of 10–20 s. The changes in thermal conductivity over time are a measure of the diffusion of N₂ through the membrane, which allows the concentration in the medium to be calculated, taking temperature into account.

The calculation for the concentration of N₂ is achieved using the change in thermal conductivity in the measurement chamber, also taking the temperature into account.

Since the thermal conductivity of oxygen is similar to that of nitrogen, a second channel may need to be used to compensate for any oxygen in the medium [1].

The total gas pressure in beer is measured after the beer has been forcefully shaken. The carbon dioxide is then bound through the addition of potassium hydroxide. The amount of air in the beer contributes the remaining volume of gas. Once the value for the total pressure has been corrected by subtracting the quantity of air present in the beer, the carbon dioxide can be measured [1].

Through heating and shaking, the gases contained in beer are collected in a burette filled with potassium hydroxide. The carbon dioxide is bound by potassium hydroxide, and the remaining volume of gas, consisting of oxygen and nitrogen, is measured [1].