Monday, April 30, 2007 - 4:00 PM

Simple and convenient on-line monitoring of alcoholic fermentation in laboratory experiments

Emo Van Halsema, Halotec, Röntgenlaan 5a, Zoetermeer, 2719 DX, Netherlands, Wim De Laat, Royal Nedalco, Van Konijnenburgweg 100, Bergen op Zoom, 4612 PL, Netherlands, and Hans Van Dijken, Bird Engineering B.V., Westfrankelandsedijk 1, Schiedam, 3115 HG, Netherlands.

Monitoring of alcohol formation is invaluable in experiments aimed at improving industrial processes for production of potable alcohol and bioethanol. This can be done with a variety of techniques such as registration of weight loss due to CO2 production, colorimetric assays and enzyme electrodes based on alcohol oxidase, standard enzyme assays with alcohol dehydrogenase, gaschromatography, HPLC and other physico-chemical devices. Measurement of the rate of alcohol production can be applied for testing the quality of the feedstock and for strain optimization. It is a laborious enterprise and frequently troubled by complexity of the medium leading to interference in enzyme assays  and fouling of (pre)columns in chromatographic procedures. In our presentation we will present results with an alcoholic fermentation monitor (AFM) that simultaneously records rate and total gas formation on line via a massflow meter coupled to a computer. The system can simultaneously measure gas formation in six magnetically stirred bottles. The temperature is controlled electrically in each  individual bottle at a value of choice.