Sensory analysis often seems like sheer chaos:
we taste our coffee and are supposed to evaluate the quality or recognize faults.
We are supposed to describe properties such as mouthfeel or put flavor into words.
We expect a sip on the spoon to tell us which parameters we should adjust in the roasting process.
But how the heck are we supposed to recognize all this from sipping once or twice, when we sometimes only recognize on the tongue whether we like it or not? Such a "sip" of coffee is gone so quickly and then we are supposed to analyze it and remember all the details at once?
This article is for you if you....
- Need a rough guide to finding your way around sensory science
- You are interested in how to break down the big topic of sensory into small bites
- Finally want to see the topic of sensory a bit more clearly
- You want to know where you can start training your skills
Your 3 party appetizers
Sensory has a framework, just like roasting, like texts, like a roasting machine, like a portafilter. All the parts make sense and when you know what to look for, the fog clears and suddenly everything becomes very, very clear. And then it's even more fun!
So let's set about breaking down the misshapen field of sensory into small, more easily digestible party morsels. Let's take a closer look at these three morsels:
- Human physiology and anatomy: Touch, Taste, Smell
- Basic taste and aroma
- Sensory analysis and testing methods
#1 Human Physiology and Anatomy
If we want to bring some order to the sensory chaos, we first start by understanding how we smell, taste and feel. So we ask ourselves which of our senses are in demand in the first place. Sight, for example, tends to be a hindrance, so visuals don't play a role in sensory evaluation in coffee. With cheese or wine, it may be different.
Let's take a brief look at our required senses:
Smelling takes place via the nose (orthonasal) and via the connection in the pharynx (retronasal). Information is transmitted directly to the brain via the nasal roof.
Tasting takes place via the taste buds of the papillae in the oral cavity. We detect whether coffee triggers one or more of the basic tastes.
Sensing also takes place in the oral cavity. We feel the temperature of a coffee, i.e. how warm or how cold it is. We also sense whether the coffee hurts. This happens with coffee rather in connection with too high temperatures. Pain reactions such as those triggered by chili or pepper are rarely triggered by coffee. Last, we perceive pressure and touch in the oral cavity.
It is very useful for us to know where the sensations are triggered by coffee and which path these sensations take. We now expand this base to include our understanding of basic taste and aromas.
#2 Taste and aroma
Sweet, salty, sour, umami, bitter - These five basic tastes can be triggered by coffee. Yet each basic taste serves a different function in our bodies:
Sweet indicates readily available carbohydrates to us, as well as some protein, which can taste sweet.
Salty points us to foods that contain salts and other minerals that are vital to us.
Sour can give us a hint of food that has gone bad.
Umami indicates that there is a high content of amino acids in a food. We translate the Japanese word as "spicy."
Bitter taste performs a warning function in the body. It may be a problematic substance that we are facing.
We can train each basic taste separately, for example sweet or sour, or in different combinations, for example sweet-sour or sour-umami.
We can increase the level of difficulty even more if we build up each basic taste again in different intensities. Because there is no 08/15 standard flavor for "sweet" or "sour". We always dissolve a lot of sugar or citric acid in water and modulate different intensities in this way.
And what about flavors?
We perceive aromas in two ways: orthonasally via our nose and retronasally via the pharynx. Perception via the pharynx occurs in conjunction with the sensations of taste and the sense of touch. We know this under the term flavor.
In our communication we distinguish between these two types and also in coffee score sheets these two sensations are recorded separately. On the one hand, we record aroma (orthonasal perception) and flavor (retronasal perception of aromas, texture, taste).
Aromas are volatile and love the connection with the air. Aroma molecules therefore push to the surface in coffee water and disappear into the environment.
We can train the perception of aromas. It is ideal to train aromas separately from each other, as mixtures can lead to a so-called overshadowing effect. And once we have saved flavors under one name, it is very difficult to save them under another name.
So now we have our basis of building our physiology and anatomy of tasting, smelling and feeling, as well as an understanding of our basic tastes and aromas.
Now we bring all of this together with coffee. And that brings us to our third party tidbit, the overview of sensory testing methods.
#3 Sensory analysis and testing methods
What at first sight may sound very formal and complicated, on closer inspection is a useful system that helps us analyze sensory quality (believe me).
We divide these testing methods into those for coffee professionals and those suitable for consumers. The tests by professionals are always analytical tests. The testing by consumers are always hedonic testing.
In hedonic testing, we ask consumers whether they like a coffee or not. So we ask them about the acceptability of taste. Likewise, we can ask consumers about their preferences ("preference tests"). There are different methodological procedures for both types of tests, which are statistically evaluated at the end.
Hedonic tests are charming for consumers because they assume no product knowledge and are subjective. Practically, anyone can participate and say whether they like a coffee or not.
For us coffee professionals, the area of analytical testing is relevant. These are standardized tests without personal influences. We distinguish between difference tests and descriptive tests.
Everyone has already done or heard of differential tests: these are comparisons of two or more products, such as the triangle test or the in/out test.
Descriptive tests, on the other hand, describe products qualitatively and quantitatively, i.e. in terms of quantity and in terms of the quality of a property, for example acid. These include the simple descriptive test or the consensus profile method.
ISO or DIN are available for all tests, which means that there is standardization and a common understanding and definition of procedures and requirements.
In coffee, we also apply a standard, precisely, the cupping protocol.
Summary: Let's look at our party appetizer plate.
Let's look closer at our party appetizer plate. We lay a solid foundation by looking at the physiology and anatomy of tasting, smelling and feeling. To this we add knowledge of basic tastes and flavors. And we put all this to practical use on coffee in various testing methods.
The testing methods we use as coffee professionals are always of an analytical nature. We break down the coffee on our spoon into its characteristics (sweetness, acidity, body,...) and evaluate them. Or we compare coffees with each other in triangle or in/out tests. There is a suitable test for every goal.
What can you do for yourself?
You now have a better idea of the field of sensory science and it is no longer one big lump, but some, small party morsels.
Depending on your knowledge and skills, you can now start training at different points for yourself:
- You can deepen your theoretical knowledge of anatomy and physiology or train your perception of basic tastes and aromas.
- You can also practice various coffee tasting tests. So some things you can already do and practice for yourself.
Additional value is added to any sensory training course by exchanging ideas with other coffee professionals. When the opportunity arises, the motto is: Do it!
We have described some tips for improving your sensory skills in this article. Have fun practicing and getting better!