Why does the coffee powder smell delicious and attractive, but it doesn't smell so good when it comes out? It runs.

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It seems that many friends prefer smelling coffee to drinking coffee. Some friends don't necessarily like coffee, but they are often attracted by the smell of freshly ground coffee powder.

When the aroma of coffee powder, after brewing into liquid coffee, will feel less fragrant? Why is that?

Compared with taste, our sense of smell is much stronger, and its sensitivity is ten thousand times that of taste. We have more than 400 olfactory receptors that can recognize more than 1 million odors. This is one of the important reasons why coffee smells better than it tastes, because the aroma captured is so rich that it can bring different experiences to the brain.

In addition, most of the more than 850 aromatic substances in coffee are volatile, so they can only be identified by the sense of smell, while some of them are bidirectional in volatilization and water solution, so they can be sensed by smell and taste, and some of the aromatic substances are purely water-soluble, accounting for the smallest proportion of coffee ingredients, which depends on taste bud identification.

Some sweet and sour flavor molecules are volatile and water-soluble, so the sense of smell can be enjoyed; but the unpleasant bitter and salty taste is water-soluble and not volatile, and only the taste can be felt. In other words, smell cannot smell bitterness and saltiness. No wonder "smelling coffee" is more enjoyable than "drinking coffee". Many people would rather smell coffee than drink coffee, just to avoid the bitter taste of coffee.

Other studies have shown that coffee doesn't taste so good because the taste buds destroy almost half of the molecules that make it fragrant. The study found that the aroma of coffee contains 631 chemicals, and because the taste buds contain amylase, 300 chemicals in the aroma are changed or destroyed by the taste buds.

The composition of coffee flavor

○ coffee flavor < Flavors > = volatile aroma < Gases > + water soluble taste < Tastes > + taste < Mouthfeel >

○ volatile aroma = dry fragrance + wet fragrance = prenasal and postnasal olfactory

○ water soluble taste = sweet, sour, bitter, salty and fresh = oral taste

○ taste = smoothness and astringency = oral touch, which is the result of the interaction of different proportion of sweet, sour, bitter and salty.

Smell better than drink, because coffee beans in the roasting process, through the "Mena reaction", mixed with esters, aldehydes and other volatile components or organic acids.

Coffee is blessed with a large and complex variety of chemicals, including other organic acids, inorganic acids, plant alkaloids and so on.

When grinding or brewing, these volatile components or organic acids are gasified to give us a pleasant aroma of coffee.

"sense of smell before nose" and "sense of smell behind nose"

Although coffee appreciation requires smell, taste and taste to perform their respective functions and complement each other in order to construct a complete sensory world, the size of the radar map for human sensory detection of flavor is in the following order: smell > taste > taste.

The breadth and accuracy of olfactory recognition is greater than that of taste and taste, because smell is the only sense with two-way function. The nose can smell the smell of the external world, that is, the "prenasal smell" (Orthonasal olfactory), but the mouth can also "smell" the smell of food eaten into the mouth, that is, the "Retronasal olfactory".

To put it simply, it is because we have two senses of smell: one is the "pre-nasal smell" when you inhale from the external environment, and the other is the "postnasal smell" when the smell is exhaled through your nasal cavity.

In addition to using the sense of smell in front of the nose, the tester or wine taster is better at the sense of smell behind the nose in order to complete the task of taste measurement.

Coffee has volatile aroma of caramel, cream, sour, flower, fruit, herb, nut, grain, resin, wine, spice, coke, soil, firewood and potion. The gasification components are all presented by the sense of smell in front of the nose and behind the nose.

However, the recognition of aroma and the excitement caused by the two are different. Before appreciating the aroma of coffee, it is necessary to understand the difference between the sense of smell before and after the nose in order to get twice the result with half the effort.

How to taste the flavor of coffee?

○ volatile aroma

When the coffee is ground, the sour aroma of flowers and fruits with light molecular weight is highly volatile, which is released first and can be smelled from afar.

This is followed by medium molecular weight caramel, nuts, chocolate and almonds, but the dispersion distance is shorter than the former and needs to be a little closer.

Finally, there are high molecular weight aromas of turpentine, mercaptan and coke. Because the molecules are the heaviest and the fragrances are the shortest, most of these smells are found in medium-to-deep roasting, and you need to keep your face close to the top of the coffee powder.

Therefore, when appreciating coffee, when smelling dry aroma, you need to change the distance between nose and coffee powder, so that you can smell multiple aromas of low, medium and high molecular weight.

Some volatile aromas cannot be gasified at room temperature and need to be boiled in hot water to release the aroma, which is the wet aroma of coffee.

Water-soluble taste of ○

When the aroma is gasified and volatilized during grinding and brewing, it is not integrated into the coffee liquid, so when the coffee is imported, the oral taste can only tell you that the coffee is sour and bitter, which is the role of water-soluble flavor molecules such as sweet, sour, bitter, salty and fresh coffee.

In principle, these five tastes can be felt in all areas of the tongue, but the tip of the tongue is sensitive to sweetness, both sides of the tongue are sensitive to acid and salt, the root of the tongue is sensitive to bitterness, and the delicious taste can be tasted by the whole tongue.

○ taste

The taste is the result of the mutual restraint and combination of the five tastes of sweet, sour, bitter and salty. Blindly too prominent, will inhibit or bless the performance of other tastes, and even affect the taste.

For example, if the salty taste is too high, if you encounter something sour, it will magnify the astringency; if you encounter a sweet taste, the salty taste will be suppressed and become mild and palatable, and the salty taste will sometimes counteract the bitter taste, and the sweet and sour taste will lead to a delicate fruit taste, which is the most popular taste.