An effective way to minimize drifting and monitor the performance of a sensory panel during long-term projects - A case study from a project on herring quality

A quick and easy way to monitor the performance of individual sensory assessors during long-term fishery projects was presented. By serving the same product as a reference before each session, assessors could easily recapitulate the descriptors and recalibrate their evaluations to the same scale. No drifting was found during an evaluation period of 19 months, and this was a result of the continuous use of the reference.

Serving the reference as an unknown sample made it possible to monitor the performance of the panel. Multivariate data analytical techniques allowed for quick calculations, and results were easily interpreted with the visual layout. Assessors differing from the rest of the panel could be quickly identified as well as the descriptors involved in the deviations.

Three assessors were found to use different parts of the scale than the main panel, and one assessor evaluated one descriptor differently than the average panel. After correction for level effect, no difference existed between assessors