Flow-injection systems for the determination of oxidoreductase substrates: applications in food quality control and process monitoring

✍ Scribed by I Ogbomo; R Kittsteiner-Eberle; U Englbrecht; U Prinzing; J Danzer; H.-L Schmidt

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 519 KB
• Volume: 249
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(91)87016-z

✦ Synopsis

A flow-injection system with immobilized dehydrogenases, including sample pretreatments by means of a continuously working filtration unit for elimination of microorganisms and a dialyser, was applied to the parallel determination of glucose and ethanol during a baker's yeast fermentation.

The system was stable for at least 17 h and very reproducible results were obtained. Two further systems for parallel monitoring of glucose and glucose-containing carbohydrates were developed for the determination of sucrose and pullulan. Both systems are based on the hydrolysis of the disaccharide or polymer and subsequent glucose determination with immobilized glucose dehydrogenase. The concentrations of sucrose and pullulan are obtained from separate determinations of free glucose and total glucose after hydrolysis. The flow system for sucrose was successfully applied to the analysis of fruit juices and lemonades.