Aroma-constituting compounds relevant in monitoring baking and roasting pro
cesses are identified. The selectivity of oxide sensor elements for these s
pecies is investigated. Examples show that the response of oxide sensors an
d the response of the human nose both depend strongly on the oxidation stat
e of the molecules. Mesomeric effects are found to be favourable for detect
ion. (C) 2001 Elsevier Science B.V. All rights reserved.