Must fermentation progress monitoring by polymer coated capacitive vapour sensor arrays

The present work deals with the task of monitoring the fermentation progress of grape must with a gas sensor array, without the use of pre-concentrator steps. The sensor array consists of eight interdigitated capacitors, coated with different polymeric materials through a well, formatted around the capacitor. The fermentation process of a particular must was duplicated under laboratory conditions and monitored in terms of (a) standard chemical analysis and (b) the response of the sensor array to the headspace of must samples, on a daily basis. PCA analysis revealed that a successful fermentation follows a distinct curve not related to that obtained from a series of equivalent pure ethanol solutions.