Potentialities of a modified QCM sensor for the detection of analytes interacting via H-bonding and application to the determination of ethanol in bread

The capabilities of a previously developed sensor based on quartz crystal microbalance (QCM) were evaluated by using the QCM as detection unit for gas chromatography. Detection and quantitation limits towards eight compounds chosen on the basis of the coordination properties of the receptor were calculated obtaining the lowest value of limit of quantitation in the case of ethanol (LOD = 1.73 × 10−2 μg; LOQ = 3.69 × 10−2 μg). A novel and simple method for the determination of ethanol in bread was then developed and applied. The device proposed was proved promising as “on-line sensor” for quality control during bakery production for ethanol concentrations ranging from 0.26% to 1.70% (w/w) in whole-meal bread and from with ethanol concentration ranging from 0.68% to 2.06% (w/w) in durum-wheat bread.