ISO 13301:2002

• obtaining data on the detection of chemical stimuli that evoke responses to odour, flavour and taste by a 3-AFC (three alternative forced choice) procedure;
• the processing of the data to estimate the value of a threshold and its error bounds, and other statistics related to the detection of the stimulus.

Typically the procedures will be used in one of the following two modes:

• investigation of the sensitivity of assessors to specific stimuli;
• investigation of the ability of a chemical substance to stimulate the chemoreceptive senses.

(Although experiments may encompass both modes.)

Examples of the first mode include studies of the differences among individuals or specified populations of individuals in sensitivities and of the effects of age, gender, physiological condition, disease, administration of drugs, and ambient conditions on sensitivity. Examples of the latter mode include:

• studies in flavour chemistry and the impact of specified chemicals on the flavour of foods;
• classification of chemicals, if present in the environment, for their impact on humans;
• studies on the relationship of molecular structure to capacity of a chemical to act as a stimulant;
• quality assurance of gaseous effluents and of water, foods and beverages;
• studies in the mechanism of olfaction.