Effect of calculation methods and presence of false positives on perception thresholds

International audiencePerception thresholds are commonly used in food science to discriminate between those compounds that are more or less odour-active. It is not rare to use values from other studies and apply them to our data, however, we observed that the procedure to evaluate and calculate perception thresholds is not standardised. The aim of this study was to explore the influence of calculation methods on threshold values. To do so, we used a 3-AFC sensory procedure to determine the orthonasal and retronasal detection values of 26 compounds, amongst them some compounds that usually contribute to the aroma of strawberry and caramel (e.g. vanillin, Furaneol and damascenone). The thresholds were calculated by either Best Estimate Threshold (BET) method or by logistic regression. Moreover, an algorithm for the removal of false positives was applied to adjust the assessors' raw responses (raw and adjusted data). The results showed significant effects (p