Phenomena of GC‐O Analysis ‐ Training and Validation of a Sensory Panel

The GC‐Olfactometry (GC‐O) method is not just relevant for the analysis of odour active substances (olfactory active volatile organic substances, oVOC) in food, but also for the analysis of odours and off‐odours from food contact materials and consumer goods. From an analytical point of view, GC‐0 is the method of choice and it is an important tool for the identification and quantification of oVOC, but this method also has its pitfalls. This study deals with the scientific presentation and summary of the phenomena of GC‐0 analysis, as well as methods for validation and training of a sensory panel. The oVOC are analysed using a GC‐FID/ODP (olfactory detection port). GC‐MS is also used as a supporting tool e.g. to ensure the purity of the reference substances. In this study, a panel was initially trained for GC‐0 [1] and mixtures of various odorous substances were developed for training purposes, whereby the odour‐active substances are relevant for both consumer goods and food [2]. Different methods are used to evaluate the GC‐0 data and their advantages and disadvantages are discussed. Firstly, panellists' individual detection thresholds of the reference substances und their reproducibility have been determined by successive dilution of the mixtures. In addition, the variance in the panel due to individual differences have been demonstrated. Furthermore, the dependence of the change in odour intensity on the change in concentration is shown and thereby different substances showing different decreases in odour intensity when diluted by the same factor. The results underline the importance of considering individual differences and the reproducibility of results. The development of a training mixture of different odours contributes to the improvement of panel work and enables a more precise analysis of food contact materials and consumer goods.