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Discrimination methods From July 2018 newsletter

Comparing discrimination methods: Triangle vs Tetrad


The Triangle test has been long established in the food industry to pick the 'odd one out' of three samples, as a means of measuring the impact of an ingredient or process change on the overall sensory character of a product. A newer method, the Tetrad test, is similar but four samples are presented instead of three and assessors are asked to form two groups of two samples based on similarity. A Tetrad test can require fewer participants.


We carried out a study (with 29 participants) to determine whether Tetrad testing could be an alternative to Triangle testing, whether Tetrad testing is applicable for testing different product types and if fewer assessors are required for a Tetrad test.


Four product types were selected for testing: biscuits, ready meal sauce with rice, juice and soup. No obvious differences were found between the Triangle and Tetrad tests so Tetrad testing could be used an alternative to Triangle testing.


Contact: Natalie Jinks
+44(0)1386 842201
natalie.jinks@campdenbri.co.uk