On-line HS-SPME-qMS quality and process monitoring of roasted food

The flavour quality of a roasted food depends on the roasting process to which it has been submitted. Correct conditions for industrial roasting process are in general obtained from a suitable scaling up of the results of experiments carried out in pilot or laboratory plants monitored by on-line easy and fast control methods. This study deals with a non separative HS-SPME-MS approach in view of its application to on-line monitoring of a roasting process (Pérez Pavón, Marsili). HS-SPME is a high concentration capacity technique characterized by high and reliable recovery, it is easy to automate and to be directly on-line combined with mass spectrometry (MS-nose or mass sensor). The resulting system can give quick representative and diagnostic fingerprints of the volatile fraction of samples in a set and in combination with a suitable chemiometric analysis (Armanino, Rodriguez) can successfully be applied to characterize, differentiate or discriminate them. TIC fingerprint or diagnostic ion abundance(s) can therefore be successfully used both as marker or as Analytical Decision Maker (ADM) (Sandra) to monitor roasting processes on-line and in the definition of quality of roasted food. The experimental HS-SPME-qMS results in the monitoring of coffee and hazelnut roasting process are here reported and critically discussed.