Automatic Control of pH Value in Cultures of Micro-organisms

Abstract
SUMMARY: Equipment for the automatic control of pH value in cultures of micro-organisms is described. The apparatus was designed for a 2 1. scale continuous culture apparatus. The equipment will continuously control pH value with an accuracy of ± 0·05 unit for periods of many hundred hours. The pH value may be changed at will by turning a knob on the controller. It is sufficient to check the pH meter standardization once every day or two. The main components of the apparatus are standard commercial products.