The Effective Assessment Effective assessment of a coffee's sensory attributes is a big part of how we value coffee, particularly in the specialty coffee world. Effective assessment differs from descriptive assessment in some important ways. And understanding the difference between the two is a big part of appraising a coffee's value. Whether descriptive assessment answers the question, what does a coffee taste like, effective assessment can answer a different category of questions such as these two, do I like the coffee and how much, and is the coffee of high quality.
In sensory science the definition of effective assessment is as follows. It is, any method used to assess acceptance, liking, preference, or emotions for a stimulus or stimuli. But what does that mean in the context of a coffee cupping? We might use descriptive analysis to objectively evaluate the constituent flavors of the coffee. But how do we measure the effective responses to these flavors?
In the coffee value assessment, we've developed a term that captures the essence of effective assessment in a coffee cupping, and we call it the impression of quality. The impression of quality is a coffee taster's opinion of the distinctiveness and desirability of a coffee sensory category, reflecting either their own preference or a known market preference. Let's explore these ideas a bit. The first is easy. Your preference is a coffee you think is of high quality.
This is based on your own experience and knowledge as a coffee taster and your own tastes. The second category, a known market preference, is based on understood norms and preferences in the coffee industry or among consumers. This diverse conception of quality is reflected exactly in what we see among coffee tasters in the industry today. They don't score coffees identically.
Though oftentimes they reach alignment over which coffees are higher quality, this consensus is not absolute and there is always variation. This is a great strength of the coffee industry that we can recognize different attributes of coffees in different situations. So this is how a cupper switches from describing the coffee's sensory attributes to expressing their impressions of a coffee's quality.
This process relies on a cupper's expert opinion developed through experience. It's important to remember that this assessment, like all effective measures, is subjective. It might reflect a cupper's personal responses or known market preference, in other words, predicting others'effective response. Importantly, one would not expect perfect alignment between cuppers on effective measurements since they are based on individual or market preferences, which are diverse. And in fact, this is what we see.
Diversity in effective measurements in the coffee world. In sensory science, the classic tool to measure effective response is the nine-point hedonic scale, which was developed in the 1940s to measure consumer response to foods. This scale goes from like extremely, a nine, to dislike extremely, a one.
The midpoint is neutral and scores a five. The great thing about the 9-point hedonic scale is that it is easily used in a variety of contexts, even across language barriers. The smiley face scale is a great example of a 9-point hedonic scale used for children.
Here is a screenshot of the effective section of the CVA, which shows the hedonic scale in context. The cupper uses a 1-9 scale to rate impression of quality from an extremely low impression of quality to an extremely high impression of quality. This assessment is repeated for each of the eight categories of the form.
There is also space available for freely elicited terms and notes. The effective scores are converted into a 100-point scale using a formula published in the CVA protocol. To summarize, the effective assessment is based on the idea of impression of quality. It uses the 9-point hedonic scale that can be translated into a more familiar 100-point score.
And data can be validated by consistency and effective preferences over time.