Pervaporation: An interface between fermentors and monitoring

An enzymic method for the determination of acetaldehyde applicable to the on-line monitoring of this analyte in fermentors has been proposed. The volatile analyte, after its separation by pervaporation, was collected in a stream containing NAD+, KC1 and 2-mercaptoethanol. The NADH formed was monitored spectrophotometrically at 340 nm. Different pervaporation temperatures were used, thus enlarging the determination range which was established between 1–100 μg ml−1. The method, which provides excellent precision (RSD less than 3.5% in all instances) has been successfully applied to the determination of the analyte in spiked fermentation media.