Performance of evaluators in a descriptive analysis of black pepper (Piper nigrum l) from Ivory Coast

The objective of this study was to evaluate the performance of a panel in the sensory characterization of pepper from Ivory Coast through three criteria: discrimination, repeatability and agreement. Twelve trained panelists evaluated fresh, dry and ground pepper samples from seven localities during three sessions on twenty sensory descriptors. The analysis was performed by XLSTAT version 21 using the Friedman test at p<0.05 and principal component analysis (PCA). The Friedman test revealed significant discrimination for all descriptors with the highest scores for Crunchy (631.22); Floury (585.54); Smooth (683.35); Round (554.84); Rough (674.78). Repeatability was satisfactory for the majority of sensory descriptors although deviations (p<0.05) were noted for Hazelnut, Floury, Bitter and Green. The PCA showed a good agreement between judges explaining 63.56% of the total variance. Finally, the highest standard deviations were observed for the samples of ground pepper from Yakassémé (2.68), fresh from Maféré (2.56), Guiberoua (2.51) and Yakassémé (2.48) and dry from Yakassémé (2.40) reflecting sensory heterogeneity. These results validate the reliability of the panel for future analyses on the sensory profile of Ivorian pepper.