Validation of two Napping® techniques as rapid sensory screening tools for high alcohol products

• Two rapid sensory methods were validated for the profiling of fatiguing spirit products.
• Partial napping found to be more suitable for large sample sets than normal napping.
• Repeated measurements are necessary for reliable Napping results.
• Partial napping proposed as tool to familiarise panellists with fatiguing products.

Rapid descriptive sensory profiling methods are under active exploration in the field of sensory science. Methods such as projective mapping, sorting and Napping® are considered time and cost-effective alternatives to conventional descriptive profiling for generating sensory product maps. In this study, the feasibility of applying rapid sensory profiling methods to the sensory evaluation of high alcohol products was challenged based on the considerable sensory fatigue expected due to high alcohol content (38–43% a/v) and perceived sensory complexity. Napping® and partial napping was compared to conventional profiling on a small sample set of six brandies to test the basic validity of these methods. The effect of an increase in sample size on reliability, repeatability and reproducibility was also tested. The results showed that Napping® and partial napping are equally reliable for the evaluation of small sample sets (n = 6) of brandy. However, partial napping was shown to be more stable with an increase in sample set size (n = 10). The effect of replication and training on reliable Napping® results is also discussed.