Sensory analysis — Methodology — Duo-trio test

ISO 10399:2017 specifies a procedure for determining whether a perceptible sensory difference or similarity exists between samples of two products. The method is a forced-choice procedure. The method is applicable whether a difference exists in a single sensory attribute or in several attributes.

The method is statistically less efficient than the triangle test (described in ISO 4120) but is easier to perform by the assessors.

The method is applicable even when the nature of the difference is unknown (i.e. it determines neither the size nor the direction of difference between samples, nor is there any indication of the attribute(s) responsible for the difference). The method is applicable only if the products are fairly homogeneous.

The method is effective for

a) determining that

either a perceptible difference results (duo-trio testing for difference), or
a perceptible difference does not result (duo-trio testing for similarity) when, for example, a change is made in ingredients, processing, packaging, handling or storage, and

b) for selecting, training and monitoring assessors.

Two forms of the method are described:

– the constant-reference technique, used when one product is familiar to the assessors (e.g. a sample from regular production);

– the balanced-reference technique, used when one product is not more familiar than the other.

Edition	2017
Published Date	2017
Published By	International Standardization Organisation
Page Count	21

ISO

ISO 10381-6:2009

ISO 10399:2017

ISO 10426-1:2009

ISO 10472-1:1997

ISO 10545-3:1995

ISO 10574:1993

ISO 10595:2010

ISO 10617:2010

ISO 10638:2010

ISO 10651 3:1997

ISO 10651 4:2002

ISO 10651 5:2006