Detection of organoleptic faults in wine by microwave sensor coupled with molecularly imprinted silica

This paper presents a microwave liquid sensor enabling an accurate quantification of chemical species at trace levels in complex liquid. Previously, dedicated to pesticide detection (ng/L), this work is devoted to organoleptic faults in wine production. Based on microstrip technology, the shape of the microwave sensor is a trapezoidal spiral. The sensor pattern is a multiresonant microstrip circuit. Each molecularly imprinted silica (MIS) is specifically synthesized to detect a marker of wine defect. Here, two markers of oxidation in white wine are tested. The first marker is the phenylacetaldehyde which triggers a mixed flavor of age, honey and overblown rose (<20 mu g/L in wine). The second marker is 1-octen-3-one which mushroom and earthy off-flavors (< 100 ng/L in wine). The coupling between the circuit and the MIS demonstrates how the sensor can detect these chemical species in a common concentration range in French wine.