Complementary analytical measurements based upon gas chromatography-mass spectrometry, sensor system and human sensory panel: a case study dealing with packaging materials

In co-operation with packaging material suppliers and a food manufacturer the quality of different kinds of wrapping foils for chocolate bars was investigated by using the hybrid Modular Sensor System (MOSES II). To check the reproducibility and to deduce quantitative predictions a gas chromatograph-mass spectrometer (GC/MS)-unit connected to a headspace-sampler (HSS) was used as a well established analytical reference instrumentation. All analysed samples were also qualified by a human sensory panel according to the sniff-test. The different packaging material species could be distinguished in a principal component analysis (PCA). With the aid of a principal component regression (PCR) a correlation between human and technical odour perception was carried out. The odour prediction of MOSES II was very satisfying particularly if compared to the human sensory assessments. Additionally, in order to follow the sensor fluctuations the sensor responses upon exposure to a standard sample have been monitored for 5 months. The results of these measurements and the investigations of four different MOSES II units demonstrated the longterm stability of the individual sensors and the high reproducibility from system to system.