Sweetness Attributes – SCA Cupping Form – This article is part of a group of posts that explain the ten sensory attributes of the SCA Cupping Form (or SCA Arabica Cupping Form) based on knowledge from the book Sensory Science.
In terms of sensory science, Sweetness or “sweetness” in coffee is not an “objective” attribute but the product of a complex impression caused by aroma, not by any dissolved sugar.
Therefore, in cupping, Sweetness is very firmly defined by the SCA as the “impression of sweetness” in brewed coffee. The attribute descriptions noted earlier, like brown sugar or vanilla scent and most fruits, are a good indication of the impression of Sweetness in coffee.
Rating the Sweetness in cupping
Perhaps because of this broad definition of Sweetness, the SCA form does not assign a quality score or intensity scale to Sweetness, only providing an opportunity for cuppers to record its presence or absence.
However, judges use an intensity scale for Sweetness in most other scoring systems, like the Cup of Excellence competition.
Since Sweetness is considered an essential attribute in coffee, for a cupper: If a cup is considered sweet, even if it has just reached the recognition threshold, it will tick the sweetness attribute box of that cup.
If the cups are “homogeneous,” they will be marked with the same “sweetness.” However, attributes such as Fragrance/Aroma, Flavor, Balance, and Overall reflect the intensity, pleasantness, or detailed description of that Sweetness.
Regarding Sensory Science, the Sweetnes attribute assessment (or Clean cup and Uniformity) is a simple variant of a sensory evaluation method known as Check All That Apply (often abbreviated as CATA).
This rapid sensory profiling technique can help identify a product’s main organoleptic characteristics; do not judge their intensity.
In a CATA test, participants were given a list of terms and asked to confirm the terms specific to the product. In the context of cupping, this test is used to help Cupper determine if a cup of coffee has a “sweet feeling.”
- NOTE: The SCA stipulates that Sweetness should be assessed when coffee is more excellent, at around 40°C.
The mechanism of sensing the Sweetness of the taste buds
Each of the approximately 8,000 taste buds on our tongues has 50 to 150 taste receptor cells attached. This means that we have hundreds of thousands of taste receptor cells.
Among these is a particular type of TR cell: TRPM5, which plays an essential role in sensing Sweetness and temperature.
TRPM5’s high sensitivity to temperature forms the basis for the effects of temperature on the taste buds, including enhancing the ability to sense Sweetness at high temperatures and “heat taste” – the phenomenon of hot/cold temperatures acting on the tongue that evokes certain taste sensations.
As a result, soft drinks or ice cream usually have a more balanced taste when used cold and are generally sweeter when used at room temperature.
However, we cannot think that the hotter the coffee, the sweeter it will be. Recent research has found that reactions to sucrose, glucose, fructose, and maltose are most effective at temperatures between 35°C and 39°C and worsen at cooler or hotter temperatures.
Therefore, the SCA tasting standard requires coffee to cool below 71°C before tasters begin to evaluate taste attributes.
In addition, 99% of the sugar in green coffee breaks down during roasting (see also The Science of Coffee), so from a food chemistry perspective, “coffee doesn’t have a sufficient amount of sweeteners that can be felt – if only by the tongue” and at room temperature.
In addition, several studies on the multisensory integration effect (we mentioned in more detail about this effect in the book Sensory Science) demonstrate that volatile compounds that evoke sweet foods (such as vanillin or caramel) increase the perception of Sweetness.
According to the Coffee Sensory & Cupping Handbook, SCA has shown that Sweetness is most highly felt in filtered coffee – even when the brewing concentration and extraction rate are both low (compared to espresso).
In other words, at high brewing intensity or extraction rates, sour and bitter soluble compounds in coffee can overwhelm the multisensory effect of “sweet aromatics,” reducing the overall perception of Sweetness.
References:
- Primecoffea, Thuộc tính Sweetness • SCA Cupping Form, Tháng Một 29, 2023