Abbreviation for "quantitative descriptive analysis", a basic methodology for analytical food sensory tests. A descriptive (descriptive) sensory analysis aims to identify and quantify sensory product properties using an objective description of human perception and to uncover relationships between the chemical-physical components of a product and the sensory properties of this product by trained persons.
The intensity of certain properties or characteristics is measured using an intensity scale. Such a quantitative descriptive analysis, which is also referred to as profile analysis or profile testing, also enables the differences between several products to be displayed graphically with defined properties. In addition to QDA, there are also other difference tests. They are the triangle test (of three products, two are identical, the deviating one must be recognized), the ranking test (differences regarding a characteristic such as Sweet ), as well as tests regarding the Perceptual threshold (Perceiving / recognizing a certain substance).
QDA is also increasingly used in wine tasting - especially when it comes to comparing several wines with regard to defined properties or characteristics. This is supposed to sensory Tests and evaluations of wines with several participating examiners often encountered problems of different evaluation can be avoided. The main reasons for these often blatant differences are, in addition to different professions or experience, the wine tasters, different quality ideas (how is the quality measured, what is the quality standard), too little precise or unambiguously standardized terms in the wine review and wine address (how should what be described) or non-specific questions (which criteria or properties should be evaluated and how).
For example, when tasting wines, the characteristics acid. residual sugar. astringency and sustainability in the taste, as well as certain flavors (Apple, tobacco. vanilla, Lemon, etc.) in odor his. The results of the profile analyzes are usually shown graphically in the form of polar diagrams (spider plots). Each feature is shown starting from the center in the form of an axis (line) that runs outwards. The more intense the characteristic, the longer the axis. If you connect the intensity end points of all the parameters of a wine, you get your aroma diagram, so to speak. Assuming eight characteristics with identical intensity and thus axes of equal length, an octagon would result. In fact, however, the individual characteristics are differently pronounced, so that a non-uniform, cobweb-like image results.
Source: Volker Schneider in "Der Winzer 08/2006, pages 14-17"