The Continuous Fermentation of Vinegar in Tower Fermenter

Abstract

A continuous Tower fermentation system has been operated for the production of vinegar. Five different raw materials were investigated. These were: cocoa 'sweatings', a substrate derived from the cocoa fermentation 'sweat' boxes and is a highly polluting waste in the country oforigin; beet molasses, a by-product of sugar industry; malt charging wort; pure ethanol, and wine. Batch and continuous modes of fermentations were studied. The substrates were tested under different conditions of temperature and aeration rate. The influence of the medium total acidity on the productivity and specific productivity, was measured. The equation K = aµ + b was found to be valid for all substrates tested (K is the specific product formation rate, µ is the specific growth rate and a, b experimental parameters). The Tower fermenter proved to be an efficient reactor for the production of vinegar. Pilot and production scale fermentation systems were developed for the production of cider vinegar and are now commercially viable. The future of the Tower fermenter as a reactor for the production of other metabolites was also considered.