Application of Gas Analysis to Continuous Culture

Abstract

For fermentation processes involving micro-organisms such as those producing antibiotics, baker’s yeast or single cell protein, analysis of the exit gas stream has provided a means of estimating important parameters (e.g. carbon conversion efficiency, volatile substrate concentration, yield factor, productivity, biomass concentration and specific growth rate). Gas analysis has several advantages over other methods of estimating these parameters: it is non-invasive, non-destructive, accurate, continuous, and can easily be automated or interfaced to data-manipulating devises. Gas analysis has also formed an integral part of feed-back control systems in fermentations such as those used to produce alcohol, or those consuming substrates which are toxic above a critical concentration.