Basic Physiology & Anatomy in Sensory Analysis


Basic tastes and sensations.

Humans are equipped with 5 basic tastes and sensations. Let's explore each at the basic level (we'll unpack more later).


Basic Tastes of the Tongue and Mouth.

    1. Sweet: best described as sucrose. Sucrose is sugar as it occurs in nature (and elsewhere) providing a sweet, pleasant taste. Coffee is fruit and contains various levels of sucrose. Specialty coffee must have a sweet perception to be considered "specialty". Sweet is especially prevalent towards the front of the tongue.
    2. Salty: seldom do we find salt in Arabica coffee, but it can be present in some processing methods or as a defect. It can be found in many Robusta coffees. Salty is especially prevalent towards the frontal sides of the tongue.
    3. Sour: this is the perception of acidity which can be very pleasant or very uncomfortable. Malic (apple) or Tartaric (grape) acids are wonderful in coffee, but vinegar and Chlorogenic acids can also be found in some coffees due to poor storage or processing. Sour is especially prevalent on both sides of the tongue.
    4. Bitter: this is the harsh, drying or warning signal most concentrated as a feeling on the back of your tongue. Coffee is bitter due to the presence of caffeine and from roasting (especially dark carbonized coffees). Bitterness is felt when we eat medicine or chemicals (e.g. caffeine) and is often a warning signal for our survival.
    5. Umami: this is the savory, salty, fishy, cheese or meat-like sensation caused by MSG and soup broth. It is not recognized for coffee tasting or quality measures, but is mentioned here as a sensation which provides enjoyment to food consumption (felt all over the tongue).





Make sure you are not confused if asked about flavors such as Fruity, Nutty, Spicy, etc. Only sweet, salty, sour, bitter, umami are basic tastes. The tongue tastes. Read on to learn that flavor perception occurs with the nose (such as Fruity, etc.).




Basic Sensations and Their Organs.

    1. Sight: We see with the eyes. We see coffee, but that's not relevant to QC.
    2. Hearing: We hear with the ears. Not relevant to coffee sensory.
    3. Smell: We smell with the nose. The nose contributes the most to the perception of flavor and is our most important organ for coffee quality control and sensory skills. Yes, the nose is even more important than the tongue. The nose (with the olfactory system) is the most important sensory organ estimated to contribute 80% of the coffee flavor perception.
    4. Taste: We taste with the tongue and sense the 5 perceptions listed above. Note that coffee (anything) must become a liquid before the tongue can sense it. That is why we have saliva glands to generate moisture for our mouths.
    5. Feel/Touch: We feel and touch with our body and skin (including lips, tongue, mouth, throat, hands, etc.) The sense of touch is used to describe Body in Coffee. Body in Coffee is a tactile feeling which we will discuss further soon.


By combining taste, smell and touch we have a three-modal experience with coffee for sensory analysis. Sure we can see it with our eyes and hear it brewing... but the taste, smell and feel of the coffee are measured for quality grading scales.




First Olfaction and then Gustation.

  1. Olfaction: this is the scientific term for sensing coffee fragrance and aroma as it contributes to flavors or flavor descriptors in coffee. The olfactory bulb is our sensory organ which translates these signals to our brain to distinguish between nutty or floral or baking spices (for example). We do this first as coffee comes near and enters our mouth.
  2. Gustation: when we drink coffee, we take it from our mouths to swallow and gustate. This happens second. The flow of air forced down our throats with coffee liquids rebounds back up into our breathing passages with a gust of aftertaste and secondary sensation for flavor.



Please leave questions or comments below.

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PS. if you'd like to download these images or course materials see www.rocc.coffee for PDFs images and more!

https://www.rocc.coffee/foundation-modules-x5


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