Dissolved Oxygen Control on a Can Filler.

One of the issues with non counter pressure can filling is the control of the level of foam on the beer. A fine foam is needed to prevent oxygen pick up between during filling and capping on foam reduces air in head space.

Most can filler use the principle of liquid shear to force a degree of foaming in the beer during filling. The problem with this principle is that it can go too far and the foaming becomes uncontrollable until either the temperature or CO2 level in the product is reduced.

Trials using a submerged beer stone in the can pulsed with low pressure CO2 show how a layer of foam can be created on a quiet non-foaming fill. This allows much greater control of the fill level, less sensitivity to filling temperature or CO2 level. Using a filling valve with a smooth flow characteristic allows filling temperature to be slightly higher which is a great help in keeping product losses down and making the whole filling process easier to manage.

The video shows the principle and the photo the pre-filling valve equipped with foam creation attachment.