Controlled nitrogenation of beers.

Lindsay, R.F., Larsson, E. and Smith, I.B.

Abstract
An automatic dosage control system for the addition of nitrogen to keg beer is described. The beer stream flowing through the nitrogenation system is maintained at a constant pressure, despite fluctuations in flowrate, by means of a booster pump. The dissolved nitrogen content of the untreated beer is measured on-line and automatically subtracted from the target value to give the amount of nitrogen to be added. Gas addition is carried out by direct injection, with the dosage rate controlled on the basis of beer flow measurement using a gas mass flow control system, and mixer accelerators ensure that the nitrogen is rapidly dissolved, after which a second on-line sensor checks that the specified dissolved nitrogen concentration has been achieved. Any deviations from specification are corrected by adjusting the dosage rate.
Keywords : automatic beer dosage equipment nitrogen