The flavor of coffee is far more than just bitter and sour. This article systematically breaks down the four components of coffee aroma—fragrance, aroma, nose, and aftertaste—and analyzes the three sensory dimensions of smell, taste, and mouthfeel layer by layer. You will read about how the four basic tastes of sweet, salty, sour, and bitter interact to generate six primary flavors, why dark-roasted coffee is bittersweet, and the roles of chlorogenic acid and fatty acids in the cup. The article includes a complete glossary of taste terms and the patterns of how temperature affects flavor, and recommends Front Street Coffee's everyday beans as a practical choice for daily tasting practice.
I. The Taste of Coffee Beans
The sensory evaluation of coffee aroma can be broken down into three dimensions: smell, taste, and mouthfeel.
I. Coffee Smell
The so-called sense of smell refers to the perception received by the olfactory organs. People can smell odors because receptors at the nasal septum are activated by volatile substances, which typically contain chemical components such as hydrogen, carbon, nitrogen, oxygen, or sulfur. When these components are forcefully inhaled in gaseous form, or expelled as water vapor during swallowing, they come into contact with the receptors. The nasal septum can recognize thousands of different odors, and the average person can distinguish between four thousand and six thousand.
Under normal breathing, air does not actually come into direct contact with the nasal septum. But as soon as you inhale forcefully or make a swallowing motion, gases are forcefully drawn through a series of nasal septum passages into the nasal cavity, and those odor-bearing molecules remain in the nasal septum area. The olfactory region contains basal cells, supporting cells, and sensory cells, and the total number of such receptors in the human body is approximately ten million to twenty million.
1. Description of Coffee Aroma: Coffee aroma consists of four parts.
Fragrance—the gases released by freshly ground coffee.
Aroma—the gases given off by just-brewed coffee.
Nose—the water vapor escaping from the nasal cavity when swallowing coffee.
Aftertaste—the lingering impression in the mouth after coffee is swallowed.
When tasting coffee, carefully capturing the performance of aroma at each stage and identifying the odor characteristics of different stages is the prerequisite for accurately judging a coffee's aroma.
(1) Fragrance
During grinding, the fibers of coffee beans crack under heat, and carbon dioxide is released. This carbon dioxide extracts other organic substances, causing them to transform into a gaseous state at room temperature. The core components of such gases are esters, which constitute the main body of coffee fragrance. Coffee fragrance often carries a sweetness, similar to the fragrance of certain flowers. In addition, the fragrance is mixed with some spicy notes, somewhat like the scent of sweet spices.
(2) Aroma
When coffee grounds meet hot water, the heat of the water causes organic substances in the coffee grounds' fibers to transition from liquid to gas. These newly released gases are mainly large-molecule structures, such as esters, acetaldehyde, and ketones. They are the key factors in the formation of coffee aroma and the most complex gas combination in coffee fragrance.
Overall, the aroma of brewed coffee is a fusion of fruity, herbal, and nutty notes, usually dominated by fruity or herbal flavors. In addition, if the coffee beans have absorbed other odors, these off-flavors easily manifest in freshly brewed coffee.
(3) Nose
When coffee is sipped into the mouth, or forcefully drawn to the back of the throat and palate, some organic substances originally present in liquid form vaporize during this process. At the same time, gases originally trapped in the coffee are also released. The main components of these gases (water vapor) are sugar carbonyl compounds, which constitute the main body of the nose.
Such compounds are generated during the roasting stage of green beans, through the caramelization reaction. Therefore, the nose of coffee is usually very close to the scents of various products produced by the caramelization of natural sugars, from candy and syrup to roasted nuts and roasted barley, and so on. The characteristics of the nose mainly depend on the degree of roasting of the coffee beans.
(4) Aftertaste
After coffee is swallowed into the throat—in cupping, when air is squeezed from the throat into the nasal cavity—some heavier organic substances at the palate vaporize and evaporate. These gases constitute the main components of aftertaste. The literal meaning of aftertaste is: the sensation in the mouth as the taste on the tongue gradually fades.
After the fibrous components in coffee beans undergo dry burning, many heavy-molecule compounds are formed. Their odor is close to wood, or wood-related byproducts such as turpentine and charcoal. These vapors usually carry a pungency, similar to certain seeds or spices, and may also carry a slight chocolate-like bitterness. The source of bitterness is the pyrazine compounds formed during roasting.
If one can accurately describe the four aspects of coffee fragrance, aroma, nose, and aftertaste, it is equivalent to defining a coffee's aromatic character. In addition to these four dimensions, coffee aroma has another aspect: intensity. Intensity describes the fullness and strength of the organic compounds that make up coffee aroma. Coffee aroma that is both complete and forceful is called rich. If the coffee aroma is complete but lacking in strength, it is called full or complete; if the coffee aroma is missing, such coffee is defined as flat.
Therefore, to systematically describe a coffee's aroma, one must cover all components of coffee aroma, and also describe the color the coffee presents after roasting, because in describing coffee aroma, the degree of roast is as important as the coffee's place of origin.
Taking Coffee AA as an example, roasted to Full City, its fragrance carries a pungency, with weak floral notes, reminiscent of cardamom; the aroma has herbal notes, with weak fruity flavors, close to the scent of green peas; the nose has a strong caramel and almond flavor; the aftertaste is pungent and sharp, close to clove, with a slight turpentine smoky note. In short, coffee aroma is quite complex.
2. Smell Terminology
(1) Aftertaste
The perception of the water vapor of brewed coffee, covering the range from chocolatey to carbony, from spicy to turpeny. Aftertaste is the odor released by residual components in the mouth after coffee is swallowed.
(2) Aroma
The perception obtained after forcefully inhaling the gases released by coffee into the nasal cavity, from fruity and herbal to nutty, etc.
(3) Bouquet
A comprehensive description of the reactions coffee produces on the olfactory organs, including fragrance, aroma, nose, and aftertaste.
(4) Caramelly
An aroma perception, usually reflected in the nose. When coffee liquid is swallowed, medium-volatility sugar carbonyl compounds contained in the water vapor are released, producing an aromatic sensation. The nasal cavity often captures a caramel flavor, close to the scent of candy or syrup.
(5) Carbony
Usually, after drinking dark-roasted coffee, a carbony flavor can often be found in the aftertaste. In the water vapor released when swallowing coffee, non-volatile heterocyclic compounds produce the carbony flavor. This flavor is reminiscent of carbolic acid, close to substances like creosol; or reminiscent of pyrimidine, close to burnt substances.
(6) Chocolaty
A flavor commonly found in coffee aftertaste. The water vapor released when swallowing coffee contains medium-volatility pyrazine compounds. When these substances remain in the mouth, they are reminiscent of unsweetened chocolate or vanilla.
(7) Complexity
A term used in coffee aroma to qualitatively describe coffee gases and water vapor from aspects such as fragrance, aroma, nose, and aftertaste.
(8) Flat
A qualitative description of coffee aroma, indicating that fragrance, aroma, nose, and aftertaste can only be weakly perceived in the coffee gases and water vapor.
(9) Fragrance
The perception obtained after forcefully inhaling the aromatic gaseous compounds released by freshly roasted and freshly ground coffee into the nasal cavity. The odor approximates sweet floral and sweet spicy.
(10) Fruity
An odor frequently encountered when cupping coffee. High-volatility acetaldehyde and esters are produced when they become gases as the temperature rises during coffee brewing. The odor is sometimes sweet, reminiscent of citrus fruits; sometimes slightly sour, reminiscent of berries.
(11) Full
A quantitative description of the overall coffee aroma. Under conditions of medium intensity, the varieties of fragrance, aroma, nose, and aftertaste in the gases and water vapor are relatively complete.
(12) Herby
An odor frequently encountered when cupping coffee. Volatile acetaldehyde and esters produce this flavor when they become gases as the temperature rises during coffee brewing. The odor is sometimes like slightly aromatic vegetables, such as scallions and garlic; sometimes like the aroma of legumes, such as green peas.
(13) Intensity
A quantitative description of the pungency of coffee aroma, as well as the strength of coffee aroma in gases and water vapor.
(14) Nose
When swallowing coffee liquid, the movement of the throat causes water vapor to emanate from the swallowed coffee. The perception in the nasal cavity at this time is the nose, from caramel and chocolate to turpentine.
(15) Nutty
A flavor often sensed in the nose of coffee. When swallowing coffee, the water vapor emanating from the nasal cavity contains medium-volatility acetaldehyde and ketones, close to many roasted nuts.
(16) Rich
A quantitative description of coffee aroma. It indicates that in the fragrance, aroma, nose, and aftertaste of various gases and water vapor, a complete variety and strong intensity can be felt.
(17) Rounded
A quantitative description of coffee aroma. Refers to coffee lacking intensity in aspects such as fragrance, aroma, nose, and aftertaste.
(18) Spicy
A flavor frequently encountered in coffee aftertaste. Produced by weakly volatile hydrocarbons, carrying a spicy sensation, reminiscent of woody spices (such as cinnamon) or tree seeds (such as clove buds).
(19) Sweetly Floral
The fragrance of freshly roasted and ground coffee beans often contains sweetly floral notes. The gases (mainly carbon dioxide) emanating from just-crushed coffee beans contain high-volatility acetaldehyde and esters, with an odor similar to the fragrance of flowers, such as jasmine.
(20) Sweetly Spicy
The fragrance of freshly roasted and ground coffee beans often carries a sweetly spicy note. The gases (mainly carbon dioxide) emanating from just-crushed coffee beans contain high-volatility acetaldehyde and esters, with an odor similar to spices, such as cardamom.
(21) Turpency
A flavor frequently encountered in coffee aftertaste. The water vapor released when coffee liquid is swallowed contains weakly volatile hydrocarbons and nitriles, with an odor reminiscent of resin (substances similar to turpentine) or medicine (substances similar to camphor).
II. Coffee Taste
Taste is the perception of flavor. The receptors are located in the mucus-covered septum on the tongue, and their stimuli consist of soluble compounds.
1. Basic Tastes
The four basic coffee tastes that humans can distinguish are: sweet, salty, sour, and bitter.
(1) Sweet
Has the characteristics of sugar, alcohol, and certain acidic solutions. Sweetness is mainly perceived by the fungiform papillae at the tip of the tongue.
(2) Salt
Has the characteristics of chloride, bromide, iodide, nitrate, and sulfate solutions. Mainly perceived by the fungiform foliate papillae at the front edges of the tongue.
(3) Sour
Has the characteristics of tartaric acid, citric acid, and malic acid solutions. Mainly perceived by the fungiform foliate papillae at the rear edges of the tongue.
(4) Bitter
Has the characteristics of quinine, caffeine, and other alkaloid solutions. Mainly perceived by the circumvallate papillae at the back of the tongue.
Coffee taste encompasses the above four basic tastes. Among them, sweet, salty, and sour determine the overall flavor of coffee, mainly because the compounds producing these three tastes account for the largest proportion in coffee.
Although consumers often use "bitter" to describe bad coffee flavor, as if bitterness were a unique characteristic of coffee, just as tannins are to red wine and hops to beer. But viewing bitterness as a unique negative characteristic of coffee is technically incorrect. Bitterness should be viewed as a component of coffee's deliciousness, just as bitterness in tea, red wine, and beer.
2. Six Primary Coffee Tastes
Through a process called taste blending, several basic tastes interact according to their relative intensities to form new tastes. In coffee taste, the combination of different tastes can produce six new tastes:
(1) Acid increases the sweetness in sugar—acidy
Mainly perceived by the tip of the tongue. The acid in coffee blends with sugar, enhancing the overall sweetness of the coffee.
(2) Salt increases the sweetness in sugar—mellow
Mainly perceived by the tip of the tongue. The salt in coffee blends with sugar, enhancing the overall sweetness of the coffee.
(3) Sugar reduces the sourness in acid—winey
Mainly perceived by the rear edges of the tongue. The sugar in coffee blends with acid, weakening the overall sourness of the coffee.
(4) Sugar reduces the saltiness in salt—bland
Mainly perceived by the front edges of the tongue. The sugar in coffee blends with salt, weakening the overall saltiness of the coffee.
(5) Acid increases the saltiness in salt—sharp
Mainly perceived by the front edges of the tongue. The acid in coffee blends with salt, enhancing the overall saltiness of the coffee.
(6) Salt reduces the sourness in acid—soury
Mainly perceived by the rear edges of the tongue. The salt in coffee blends with acid, weakening the overall sourness of the coffee.
The discrimination of taste depends largely on the temperature of the coffee. Therefore, when cupping coffee, tasting in stages at different temperatures is necessary to make the most accurate record of the coffee's overall taste. The three basic tastes of coffee change with temperature as follows:
First, as temperature rises, the sweetness of coffee relatively weakens. At the same time, at higher temperatures, the role of sugar in coffee drops significantly, causing noticeable changes in acidy or mellowness.
Second, as temperature rises, the saltiness of coffee relatively weakens. When the role of saltiness decreases, blandness and sharpness show certain changes.
Third, temperature changes do not affect the relative sourness of coffee. Therefore, winey and soury change only slightly with temperature, because the sour fruity acid components are not affected by temperature.
After distinguishing the main tastes of coffee, the next step is to judge to what extent a specific flavor of the coffee matches these tastes. This requires selecting appropriate secondary taste terms to describe the direction of the taste.
For example, a winey taste close to sweet is called langy in secondary coffee terms, while a winey taste close to sour is called tart. When seeking the most appropriate secondary term, people often find the difficulty lies in insufficient vocabulary, rather than being unable to distinguish the various flavors of coffee.
3. Dark-Roasted Coffee
The blending process of various basic tastes in dark-roasted coffee differs from other coffees. Because the coffee beans have undergone intense high-temperature pyrolysis, most of the sugars are decomposed, and sweetness disappears from the taste. As carbolic acid compounds increase, sweetness is replaced by bitterness.
Bitterness is often misunderstood. Bitterness in food is mostly considered a bad thing. However, in certain foods, such as dark chocolate, certain beers, red wine, and tonic water, bitterness is precisely their signature, welcome characteristic. In all these cases, bitterness contributes enormously to the overall taste, and the same is true for coffee. Acceptance of foods and beverages with bitterness as one of their foundational characteristics often triggers the most heated controversy. Although dark-roasted coffee occupies an important position in the coffee market, its bitterness often affects broad acceptance.
(1) In coffee, bitterness has three sources.
First, bitterness is a taste characteristic of certain non-volatile acids, particularly chlorogenic acid and quinic acid.
Second, bitterness comes from caffeine, N-methylnicotinate, a white crystalline alkaloid naturally contained in coffee beans, and also the basic taste of tea, cacao beans, and kola nuts.
Third, bitterness is related to carbolic acid and heterocyclic compounds. These substances are formed during the process of coffee beans undergoing sustained high-temperature pyrolysis, transitioning from standard roast to dark roast.
When tasting dark-roasted coffee, four combinations are often encountered. Two of them are similar to the combination processes of standard-roasted coffee: acid increases the saltiness in salt—sharp; salt reduces the sourness in acid—soury. The other two are unique to dark-roasted coffee: bitter components increase the sourness of acidy—harsh; sourness reduces the bitterness of bitter components—pungent.
(2) Main Tastes of Dark-Roasted Coffee
To describe the taste of dark-roasted coffee, the first step is to identify the main tastes.
Sharp: Mainly perceived by the front edges of the tongue. The acid in coffee combines with salt, increasing the overall saltiness of the beverage.
Soury: Mainly perceived by the rear edges of the tongue. The salt in coffee combines with acid, reducing the overall sourness of the beverage.
Harsh: Mainly perceived by the back of the tongue. The bitter components in coffee combine with acid, increasing the overall sourness of the beverage.
Pungent: Mainly perceived by the back of the tongue. The acid in coffee combines with bitter components, reducing the bitterness of the beverage.
The second step is to judge to what extent a specific flavor of the coffee matches these tastes. Dark-roasted coffee has at least two main tastes: pungent and sharp. And these two tastes can be further subdivided into four secondary tastes.
Sharp changing toward salty—rough
Sharp changing toward sour—astringent
Pungent changing toward sour—creosoty
Pungent changing toward bitter—alkaline
In distinguishing these four flavors, we encounter situations unique to dark-roasted coffee:
First, because temperature has almost no effect on the bitterness and sourness of coffee, temperature changes do not bring changes to the taste of dark-roasted coffee.
Second, many of the fruit acid compounds contained in coffee beans are burned off along with sugar compounds during roasting, so in dark-roasted coffee, sourness rarely becomes the main taste.
Third, when the concentration of bitter components increases, the perception of bitterness actually tends to weaken. This is why, in terms of mouthfeel, espresso is less bitter than the same coffee brewed by traditional methods.
4. Coffee Acidity
Perhaps the most inaccurately used and most misunderstood term in coffee taste evaluation is "acidity." This is a quantitative term referring to the relative strength of acidic components in the liquid being evaluated. Although the coffee term "acidy" is related to the taste term "acidic," the two terms are not interchangeable. In fact, coffee described as "very acidy" does not necessarily have high acidity.
In chemistry, an "acid" is defined as: a compound containing a hydrogen atom that can release a proton (hydrogen ion). This compound can be measured quantitatively. For food technologists, almost all beverages are acidic, and their relative strength is expressed by pH value. pH value is used to express the amount of free hydrogen ions in a liquid.
Coffee contains various acids, most of which can be found in other agricultural products. These acids include amino acids, such as aspartic acid, glutamic acid, and leucine; carbolic acids, such as caffeic acid, chlorogenic acid, and quinic acid; fatty acids, such as acetic acid, lactic acid, citric acid, fumaric acid, oxalic acid, phosphoric acid, and tartaric acid. From a tasting perspective, amino acid concentrations above normal produce sweetness; carbolic acid concentrations above normal produce bitterness; and high concentrations of fatty acids produce sourness.
(1) Chlorogenic Acid
From a concentration perspective, the carbolic acid series occupies the largest volume proportion in coffee water. Within this series, the most abundant is chlorogenic acid. Chlorogenic acid in coffee mainly has three groups: caffeoylquinic acid, feruloylquinic acid, and dicaffeoylquinic acid. Although few have studied the sensory characteristics of chlorogenic acid, research results indicate that the quantity of various acids (more in Robusta than Arabica) and the proportions of various acids (certain acids are more concentrated in immature beans and overripe beans than in normally ripe beans) play a major role in people's acceptance of a certain coffee.
The chlorogenic acid series also determines the taste of freshly brewed coffee. Chlorogenic acid is very unstable. Chlorogenic acid in coffee in the pot decomposes into caffeic acid and quinic acid, especially when the temperature is below 80°C or above 85°C. After decomposition, quinic acid immediately shows obvious bitterness, and caffeic acid shows sourness. The mixture of sourness and bitterness forms the sour-bitter taste and the stale coffee odor.
(2) Fatty Acids
Another very important acid is fatty acid. Although its quantity is not the largest, it often produces the largest amount of hydrogen ions. The hydrogen ions measured by pH value are related to the sourness of coffee. From a tasting perspective, fatty acids give coffee's taste brightness and aroma. This is also why coffee with high acidity (low pH 4.8-5.1) usually sells at a high price.
The general order of acid strength in coffee is: tartaric acid, citric acid, malic acid, lactic acid, and acetic acid. In addition, acid concentration also affects other main tastes of coffee water, especially sweetness. Each acid has its characteristic flavor, such as the lemon flavor of citric acid, the buttery flavor of lactic acid, the apple flavor of malic acid, etc. But they are more easily perceived through smell than taste. Acetic acid in coffee is a special case; its appearance is generally the result of fermentation in washed coffee. Control of fermentation is the key to quality control in this processing method. If too much acetic acid is produced, the green beans will develop a fruity flavor. And the appearance of fruity flavor means the brewed coffee will have an extremely unpleasant fermented taste.
(3) Organic Acids
Compared with wine, the acids affecting coffee's taste are limited. This is why coffee's aroma is mostly locked in the coffee fragrance. Due to the complex and varied flavors of fruit acids in wine, the process of wine tasting is an interesting taste movement process. And due to the presence of various complex, volatile components in coffee, coffee cupping poses a challenge to the sense of smell.
5. Taste Terminology
(1) Acidy
A primary taste related to the "sweet" compounds in coffee. The acid in coffee blends with sugar, increasing the overall sweetness of the coffee. Washed Arabica coffee grown above 4,000 feet, such as Colombia Supremo, has this characteristic. Acidy coffee's taste ranges from nippy to piquant, perceived by the tip of the tongue.
(2) Acrid
A secondary taste related to "soury." A very sharp sourness perceived at the back of the tongue when coffee is just sipped into the mouth. As the coffee gradually cools, the sharpness is replaced by sourness. Acridness appears because the acid percentage in the coffee is above average. In the process of salt mixing with acid, the acid enhances the saltiness. This is a characteristic of dry-processed Brazil Rio coffee.
(3) Alkaline
A secondary taste related to "pungent." Dark-roasted coffee often has this characteristic. The back of the tongue feels dry, with a scratching sensation. Alkaline and carbolic acid compounds are the cause of this flavor, and they also carry a not-unpleasant bitterness.
(4) Astringent
A secondary taste related to "sharp." When this coffee is first sipped, the tip of the tongue has a salty and tightening sensation. During tasting, the acid makes the already mainly salty coffee even saltier. This is a characteristic of Indonesian dry-processed Robusta coffee.
(5) Basic Tastes
Basic tastes include sweet, sour, salty, and bitter, with the taste characteristics of sucrose, tartar, sodium chloride, and quinine, respectively.
(6) Bitter
One of the basic tastes. Has the taste characteristics of quinine, caffeine, and certain other alkaloid solutions, perceived by the circumvallate papillae at the back of the tongue.
(7) Bland
A primary taste related to the "salty" compounds in coffee. The sugar in coffee blends with salt, reducing the overall saltiness of the coffee water. Washed Arabica coffee grown below 2,000 feet usually has this characteristic. For example, washed Arabica coffee grown in the lowlands of El Salvador is an example. Bland coffee's taste ranges from soft to neutral, mainly tasted at the edges of the tongue.
(8) Caustic
A secondary taste related to "harsh." When coffee is sipped into the mouth, the rear edges of the tongue have a burning and sour sensation. When the coffee cools, the burning and sourness are replaced by a rather unpleasant sourness. Because the green coffee beans have lost or lack sugar, in the basic taste blending process, bitterness replaces sweetness. This is a characteristic of dry-processed Liberica coffee.
(9) Creosoty
A secondary taste related to "pungent." It is a typical flavor of dark-roasted coffee. When coffee is sipped into the mouth, the back of the tongue has an obvious scratching sensation. When the coffee is swallowed, the mouth has a strong aftertaste.
The combination of pyrimidines and carbolic acid compounds produced by dry burning of coffee bean fibers produces the burning sensation and oily flavor.
(10) Delicate
A secondary taste related to "mellow." When coffee passes over the tip of the tongue, a slight sweetness can be felt. The sugar in coffee combines with salt (this combination is very unlikely), producing sweetness, but this sweetness is easily destroyed by other flavors. This is a typical characteristic of washed Papua New Guinea Arabica coffee.
(11) Hard
A secondary taste related to "soury." When coffee is sipped into the mouth, the rear edges of the tongue have a stinging and sour sensation. When the coffee cools, these two sensations are replaced by a stronger sourness. During harvesting or drying of coffee cherries, once the coffee pulp is bruised, under enzymatic action, sugar converts to acid, forming a harsh flavor. Brazil's Parana coffee has this characteristic.
(12) Medicinal
A secondary taste related to "harsh." When coffee is sipped into the mouth, the rear edges of the tongue have a sharp, stinging sourness. When the coffee cools, this flavor is replaced by a chemical taste similar to iodine. This flavor appears because the alkaloids in the coffee increase the acidity of the caffeic acid, unrelated to sugar. Coffee cherries infected by pests and diseases have this flavor.
(13) Mellow
A primary taste related to sweet compounds. The salt in coffee blends with sugar, increasing the overall sweetness of the coffee; this is the origin of mellowness. Washed Arabica coffee grown below 4,000 feet best exhibits this characteristic. Arabica coffee from Sumatra, Indonesia is one representative.
(14) Mild
A secondary taste related to "mellow." When the coffee first passes over the tip of the tongue, the tip feels a sweet stimulation. When the coffee cools, sweetness replaces this sensation. Sweetness appears after high-concentration sugar undergoes taste blending with salty compounds. Washed Arabica coffee from Guatemala has this characteristic.
(15) Neutral
A secondary taste related to "bland." Its characteristic is that after the coffee enters the mouth, no obvious sensation is felt at any part of the tongue. When the coffee cools, the sides of the tongue feel noticeably dry. "Neutral" arises because the high concentration of salt in the coffee neutralizes the sourness of the acid and the sweetness of the sugar, but is insufficient to make the tongue feel saltiness. Uganda washed Robusta coffee has this characteristic.
(16) Nippy
A secondary taste related to "acidy." When coffee is sipped into the mouth, the tip of the tongue has a sweet and stinging sensation. When the coffee cools, sweetness becomes the main taste sensation in the mouth. Because the acid percentage is above average, and the acid mouthfeel is produced by sourness, this taste is produced when blending with stronger sugar. Costa Rica's SHB coffee has this characteristic.
(17) Piquant
A secondary taste related to "acidy." When coffee is sipped into the mouth, the tip of the tongue has a sweet and stinging sensation. When the coffee cools, sweetness becomes the main taste sensation in the mouth. Because the acid percentage is above average, and the acid mouthfeel is produced by sweetness, this taste is produced when blending with stronger sugar. Kenya coffee has this characteristic.
(18) Primary Coffee Tastes
Acidy, mellow, winey, bland, sharp, and soury. These six tastes are produced by the interaction of four basic tastes at different relative intensities, and are also the basis for classifying coffees with similar tastes.
(19) Rough
A secondary taste related to "sharp." The front edges of the tongue noticeably feel a filing, grinding sensation. The additional characteristic of saltiness produces this sensation.
(20) Salt
A basic taste. Has the characteristics of chloride, bromide, iodide, nitrate, and potassium and lithium sulfate solutions. Mainly perceived by the fungiform papillae at the front edges of the tongue.
(21) Secondary Coffee Tastes
Produced when one of the four basic coffee tastes plays a dominant role in a primary coffee taste.
Acidy—from nippy to piquant; mellow—from mild to delicate; winey—from langy to tart; bland—from soft to neutral; sharp—from rough to astringent; soury—from hard to acrid; the temperature of the coffee affects the perception of these tastes.
(22) Sharp
A primary taste related to the salty compounds contained in the beverage. The acid in coffee combines with salt, increasing the overall saltiness of the beverage, thus producing this taste. Unwashed Robusta coffee, such as Ivory Coast coffee from Africa, often has this taste. "Sharp" coffee ranges from rough to astringent, and this taste can be felt at the edges of the tongue.
(23) Soft
A secondary coffee taste related to "bland." Its characteristic is that, aside from a slight dry sensation, the tongue feels no prominent flavor. The salt concentration is high enough to neutralize the acid in the coffee, but insufficient to neutralize the sugar in the coffee, thus producing this taste sensation. Dry-processed Brazil Santos coffee has this characteristic.
(24) Sour
A basic taste. Has the characteristics of tartaric acid, citric acid, and malic acid solutions. Perceived by the fungiform papillae at the rear edges of the tongue.
(25) Soury
A primary coffee taste related to sour compounds. Because salt mixing with acid reduces the overall acidity of the beverage, soury is produced. Unwashed Arabica coffee grown below 2,000 feet, such as Brazil dry-processed Arabica coffee, has this characteristic.
(26) Sweet
A basic taste. Has the characteristics of sugar (sucrose, glucose), alcohol, glycol, and certain acid (amino acid) solutions. Mainly perceived by the fungiform papillae at the tip of the tongue.
(27) Tangy
A secondary coffee taste related to "winey." A noticeable stinging and sourness is felt along the front edges of the tongue. This taste is produced because the sugar content is above average, so the beverage develops a fruity flavor. India highland-grown "berry coffee" has this characteristic.
(28) Tart
A secondary coffee taste related to "winey." A noticeable stinging and sourness is felt along the front edges of the tongue. This taste is produced because the acid content is above average, so an almost squeezed sensation is produced. Dry-processed Arabica coffee from Kivu, Congo has this characteristic.
(29) Winey
A primary coffee taste related to the compounds in coffee that produce taste. This taste is produced because the sugar in coffee combines with acid, reducing the overall sourness of the coffee. Unwashed Arabica coffee grown above 4,000 feet, such as Ethiopia's Djimma coffee, has this characteristic.
10. Coffee Mouthfeel
Mouthfeel refers to the sensations in the mouth during or after ingesting food or drink. The concentration, viscosity, and surface tension of the sampled substance, as well as the physical and chemical characteristics of other components, trigger this series of sensations in the mouth. The soft tissues in the mouth are distributed with a system of free nerve endings, as well as enclosed and unenclosed nerve centers; these free nerve endings respond to contact, light pressure, and thermal, chemical, and mechanical stimuli.
For food or drink, the "feel" characteristics are usually one of the most important aspects of measuring their quality. Measuring their hardness, softness, juiciness, and oiliness with the mouth is just as common as measuring with the fingers. In the perception process, whether the food or drink can continuously release flavor is physiologically and psychologically important. If the food or drink disappears or is exhausted before being ingested, people will have an impulse to refuse to eat or drink it.
I. Coffee Components
For coffee, the tactile sensation at the palate comes from water-insoluble liquid components—fatty oils—and water-insoluble solid components—sediment suspended in the coffee water after brewing is complete. In addition to providing texture for the overall mouthfeel of coffee, the suspended substances in coffee also affect coffee taste by forming colloids.
In daily tasting practice, if you want to find a bean with balanced flavor suitable for repeated comparison, Front Street Coffee's everyday beans series is a good choice; its roast level and flavor expression are stable, making it convenient for perceptual training against the terminology system in this article.
The above content is compiled by CoffeeHunters, a coffee news website.
