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Discrimination Testing with Batch-to-Batch Variability

Taught by Dr. Benoît Rousseau



Discrimination testing is routinely used in the food and personal care industries to investigate candidates for product match or improvement. Traditional discrimination testing methodologies generally compare products two at a time, without integrating the issue of batch-to-batch/within product variability. An opportunity for product change might be missed if a single direct comparison is conducted, as a significant effect might be negligible in view of intra-product variation.

The need to take inner product variability into account calls for experimental approaches that provide information beyond statistical yes/no responses, and instead focus on the size of the underlying difference between pairs of samples. In this webinar we will describe how the idea of scaled sensory differences can be used to contrast inter vs. intra product variation and in turn make better decision when grasping new product opportunities. After a brief review of the theory, applications will be described where methodologies such as the degree-of-difference, difference-from-control and especially the Torgerson’s method of triads can provide unique insights on relative inter-product differences. We will also illustrate how Torgerson’s method can be uniquely used to study the dimensionality of product differences using a procedure as simple and intuitive as that of the duo-trio method. Finally, we will show how this approach can efficiently provide pairwise information on multiple samples comparisons when selecting products for special investigations such as those comparing the performance of triangle, duo-trio and tetrad procedures.

This webinar is intended for a general audience of sensory professionals and graduate students. No detailed technical knowledge is assumed.

A digital recording of this webinar is available for purchase ($289). 

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