When describing and characterizing the flavor of whisky and whisky malts, the phenolic content is an important indicator strongly related with the peaty and smoky flavor of a whisky. In whisky, phenolic compounds mainly originate from the smoking of barley, the thermal degradation and the maturation processes. Most often, the concentration in phenolic compounds is determined by UV/visible spectroscopy, HPLC or GC-MS.
By using the HERACLES fast gas chromatography electronic nose, Alpha MOS proposes to predict the total phenolic content in barleys, by correlating the instrumental measurement to known data on phenolic scores. A study has been conducted in our laboratory on ten batches of malted barley of different phenolic content, described by a sensory panel as having smoky and phenolic cereal notes.
The electronic nose measurement is highly correlated with the total concentration of phenols in whisky malts (correlation coefficient > 89%), which indicates that the instrument can be reliably applied to determine the phenolic content in blind samples of whisky.
In addition, the electronic nose allows to show the flavor differences that exist between the various whisky malts and thus to achieve a flavor mapping of whiskies.