Computer control of bakers' yeast production

TLDR

The study demonstrates the usefulness of computer control for producing yeast from molasses. A flexible online computer system employing anticipatory and multivariable feedback control monitored cell mass and prevented ethanol formation to maintain maximum productivity. The strategy achieved a maximum conversion yield of about 0.5 g cell/g sugar and volumetric productivity of 3–5 g l⁻¹ hr⁻¹, demonstrating that simultaneous anticipatory and feedback control overcomes oxygen starvation, molasses quality, and inoculum variability.

Abstract

Abstract The Biotechnology and Bioengineering study presented here was undertaken to demonstrate the usefulness of computer control for the production of yeast from molasses. A flexible control system was developed by using an on‐line computer for the monitoring of cell mass and employing anticipatory control to maintain the maximum productivity. Process disturbances were minimized by employing a multivariable feedback control system to prevent ethanol formation. The control strategy acted to keep overall conversion yield at its maximum level, about 0.5 g cell/ g sugar, while maintaining high volumetric productivity between 3 and 5 g/liter‐hr. Results are presented to show the effectiveness of simultaneous anticipatory and feedback contol in overcoming problems of oxygen starvation, molasses quality, and variable inoculum size.