The calculation of the score for a coffee competing at International Coffee Tasting consists of three different phases:
(1) sensory evaluation of the product by the panel of tasters
(2) statistical processing of the sensory evaluations of the panel of tasters
(3) calculation of the product score
(1) Evaluation of the product by the panel of tasters
The tasters are gathered in a panel and evaluate the product completely blindly. This means that the tasters do not know any information about the product they are evaluating (so they do not know the name, company or origin). For each product they fill in the International Coffee Tasting form assigning a score from 0 to 9 to each descriptor (a descriptor is a sensory characteristic).
(2) Statistical processing of the sensory evaluations of the panel of tasters
Using robust statistical techniques, the quality of the work done by the tasters is first assessed. Only the data provided by those who reach a minimum efficacy score are then considered and the overall reliability of the panel is assessed. Thanks to these data, the median is calculated for each individual product descriptor: the medians are therefore the judgment of the group of tasters and constitute the sensory profile of the product.
(3) Calculation of the product score
The medians of the descriptors are inserted in the formula for calculating the score, shown below and detailed in Annex A of the General Regulations of International Coffee Tasting.
Not all descriptors have the same weight in forming the final score: based on an archive of almost 2,500 coffees from over thirty countries around the world, a weight has been calculated for each descriptor, called the Correlation Index. This means, in short, that some descriptors matter more in generating the score. For example, if the group of tasters assigned a median 7 to the descriptor Texture, this generates more points than the median 7 attributed to the descriptor Roasted.
Furthermore, the descriptors are positive or negative, so they increase or decrease the final score. The positive ones are: Texture, Olfactive Intensity, Body, Acidity, Flowers And Fresh Fruit, Dried Fruits And Nuts, Roasted, Spicy. The negative ones are: Bitterness, Astringency, Vegetable, Empyreumatic, Biochemical. Finally, the score obtained is multiplied by 5.0 for categories A, B and by 4.0 for categories C, D, E, F.
Downloads (English)
Annex A – Calculation Of The Score (PDF, English)
Guide To The Calculation Of The Score (PDF, English)
Downloads (Italian)
Allegato A – Calcolo del punteggio (PDF, Italian)
Guida al calcolo del punteggio (PDF, Italian)
Downloads (Chinese)