Assessing sensory panelist performance using repeatability and reproducibility measures

Abstract

John Mandel of the National Bureau of Standards defined repeatability and reproducibility measures to assess within laboratory and between laboratory measurement variability in inter-laboratory (round robin) analytical studies. This paper will demonstrate that these same measures can be applied to the problem of assessing sensory panelist performance. Repeatability and reproducibility will be defined in the context of both analytical inter-laboratory studies and sensory panels. Formulas for the measures will be given. Examples using these measures with sensory panel data and their interpretation will be discussed. Since a typical sensory panel evaluates a much larger number of attributes compared with the number of analytical measurements in an analytical round robin test, some practical considerations as to how to use these measures efficiently will be proposed. Finally, a graphical method of displaying sensory panel data will be demonstrated as an alternative to using these measures, while keeping the repeatability and reproducibility concepts intact.