Sensory analysis is a science. No matter how subjective it may be, sensory analysis represents a decisive step during the various stages of food product development, a unique tool for determination of organoleptic properties of food and, more specifically, beer. Being a science, sensory analysis requires care in planning and diligence in execution. Sensory tests must comply with very specific standards, in particular through the establishment of certain ideal conditions to perform the experiments.
The ideal conditions for the sensory experiment
Regarding the place where the tests are conducted, both temperature and humidity must be constant and easily controllable. In general, a temperature of 20 ± 2 ° C and relative humidity between 60% and 70% is recommended. The place should be free of external noises, well ventilated and free of odors. Also it should be coated with a material that is easy to clean, odor-free and that does not absorb odors. Therefore, carpets, wall paper, porous tiles, etc. should be avoided.
The colour of the test site and equipment must be neutral (white or light gray) so as not to influence the evaluation of the beer. Lighting is also a crucial factor, especially when evaluating the appearance. The lighting of the test room should be uniform, shade-free and controllable. Lamps with a color temperature of approximately 6500K are recommended. When tasting, one should avoid evaluating beers within two hours after lunch. The best time to conduct this type of tests is between 10:00 p.m. and lunchtime, or later in the afternoon, although this may vary from taster to taster, depending on their biological rhythm.
The ideal moment for the tasting is when the taster is more awake and his mental abilities are at their maximum.
How the surroundings may affect the sensory perception
Group effect – when a good beer is put in a group of mediocre beers, the rating will be lower (and vice-versa);
Central tendency error – tasters tend to rate the beers in the center of the scale, avoiding very high or very low scores;
Expectation error – if you are told you will be drinking a Westvleteren XII, the expectations about the sample will be very high. To avoid preconceived ideas, details about the sample should be minimal;
Mutual suggestion – happens when a reaction of a person influences the perception of the other;
Lack of motivation – some testers might be uninterested and in consequence put less effort on the experiment.
Promoter of the Portuguese National Homebrewing Contest. Graduated from KU Leuven (Belgium) in beer sensorial analysis, being certified as Beer Sommelier and Beer Judge by the Beer & Cider Academy (Institute of Brewing and Distilling). Certification in Beer Tasting and Beer and Food Matching by the Prague Beer Academy. Bruno is a beer writer for important publications such as Expresso, Público and Drinks Diary. He is an invited beer judge for national and international beer competitions.