Discrimination testing is a technique employed in sensory analysis to determine whether there is a detectable difference among two or more products.
[1] The statistical principle behind any discrimination test should be to reject a null hypothesis (H0) that states there is no detectable difference between two (or more) products.
The statistical test chosen should give a probability value that the result was arrived at through pure guesswork.
Tests used to decide whether or not to reject H0 include binomial, χ2 (Chi-squared), t-test etc.
The type of test determines the number of samples presented to each member of the panel and also the question(s) they are asked to respond to.