Sensor device

A gas sensor device for detecting boar taint in a gas sample of volatised boar fat 5, comprises; a first sensor 2 to provide a first signal indicative of VOCs detected in the gas sample; a second sensor 2 to provide a second signal indicative of VOCs detected in the gas sample; wherein the first sensor is more reactive to target gases indicative of boar taint than the second sensor; and a volatising heating device 1 configured to volatise boar fat. A method includes using a difference between i) a change in a signal of the first sensor over a sampling period and ii) a change in a signal of the second sensor over the sampling period to differentiate between a presence or absence of boar taint. Target gases are androstenone, skatole, indole, or androstanol, or derivatives thereof. The sensor comprises an enclosure 3 with gas purge inlet.