Change in the dissolved oxygen concentration

Start of the measurement

As oxygen is dissolved in the culture medium, small amount of electric current depending on the oxygen concentration will flow and be detected.

End of the measurement

If proliferated bacteria consume the dissolved oxygen, the amount of electric current sharply drops in proportion to the amount of oxygen consumed.  Proliferation of bacteria can be easily detected in this way.

Incubation time and current value

In the DOX system, the time taken for the current value to change will be converted into a bacterial count.

The more bacteria, the quicker dissolved oxygen is consumed and the sharper the current value drops.

This means, the more bacteria exist in the food sample, the quicker it can be detected and proper countermeasures taken.