Research Methodology
9 Measuring perception: commonly used techniques
An important distinction that is made in sensory research is direct versus indirect scaling techniques. As the results that you get from these tests differ, it is important to consider what kind of information you want, before you choose your study procedure. Ranking and triangle tests are typical indirect techniques and QDA is a direct technique. In addition, there are many variations and combinations of these methods that can be thought of. However, these go beyond this introductory course and will be discussed in the more extended course HNH-30506 Principles of Sensory Science.
Different types of scales
Visual analogue scale
A visual analogue scale, often abbreviated to VAS in research, is usually a 10cm or 15cm scale on which participants or panelists have to rate analytical attributes. An example of a visual analogue scale can be seen below. The output of this scale gets translated to a number between 0 and 100.
9-point labeled hedonic scale
An example of a hedonic scale is the 9-point hedonic scale. This scale is used for hedonic questions in sensory research. This scale has nine anchors on which participants or panelists have to rate to what extent they like the product or sample.
Other scales
Other scales used in sensory research can be the 5- or 7-point hedonic scale, which is similar to the 9-point hedonic scale, but this one only has five anchors. Another scale is the generalized Labelled Magnitude Scale (gLMS). It measures the perceived intensity of sensory properties using a vertical scale with labels from “barely detectable” to “strongest imaginable.” It can used in sensory science to quantify and compare sensory perceptions.
In the Dutch context, the Dutch grading system, anchored from 1 to 10 may be used.
For sensory research with children, often scales with smiley faces representing the sensation are used.
In direct scaling techniques, questions are asked that directly affect the sample. For example: how sweet is the sample.
In indirect scaling, samples are compared to eachother. For example a ranking test (one solution is more sweet than another).
Visual Analogue Scale: a rating scale measuring the response from 0 to 100.
Analytical testing refers to the objective measurement of the intensity of a sensation
Scale with 9 anchors used for hedonic questions.
hedonic testing refers to the subjective evaluation of a sensation, for example, liking or palatability.