What is the fragrance of coffee beans? why the aroma of coffee beans comes from inexplicable chemical reactions.

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Qianjie-introduction to the source of coffee aroma

Aroma, flavor, aftertaste, acidity and alcohol thickness-all five properties are collided by different compounds. On the cup table, we use our senses to analyze the taste and aroma, which are also caused by chemical compounds. First we smell the dry incense, then the wet incense, and finally the sucking tasting. At each stage, there are different molecules at work.

Some non-volatile compounds that you should know

When we talk about non-volatile compounds, we should emphasize alkaloids (caffeine and trigonelline), chlorogenic acid, carboxylic acid, carbohydrates and polysaccharides, lipids, proteins, melanoids and minerals.

Caffeine is soluble in water and can affect the strength, bitterness and mellow thickness of brewed coffee. Another essential alkaloid is trigonelline, which is also the source of the aroma of roasted beans and coffee.

Chlorogenic acid: the important thing about understanding chlorogenic acid is that they are formed from trans cinnamic acid and quinic acid. Let me explain: quinic acid dominates the bitter and astringent taste of coffee, which is also the source of these flavors. Chlorogenic acid degrades during baking, which means we feel an increase in quinic acid. This is one of the important reasons why deep-baked beans taste bitter.

Organic acids: now let's talk about what high-quality acids are. This is a key attribute of coffee quality and is related to sweetness.

Carbohydrates and polysaccharides: some polysaccharides are forms of carbohydrates, such as mannan and cellulose. These sweet compounds play a vital role in retaining volatile compounds in coffee, that is, increasing the aroma of coffee. In terms of flavor, these compounds are also related to the alcohol thickness of coffee. Moreover, smaller glucose and fructose can increase the sweetness of coffee.

Lipids help to improve the taste of coffee. They are extracted from beans and are the protagonists of CREMA on the surface of espresso. The baking process doesn't really affect its content, but in the baking oven, lipids do seep out to the surface of the coffee beans.

Finally, we will talk about melanoid, which is the product of Maillard reaction: the reaction between amino acids and carboxyl groups of reduced sugars. They are macromolecules, the substances that make coffee beans brown, and at the same time, they increase the taste when brewing. This means that the amino acid content of coffee is closely related to its quality, the more amino acids, the more reaction, the more melanoid.

Note, however, that the color of coffee is not only caused by melanin, it is also the result of caramelization of sugar.

Knowledge: shallow roasting is mainly sour and flavor, if the baking is not handled properly, there will be a sense of astringency and irritation, while the mellow thickness and flavor of coffee feel lower.

In short: Qianjie is a coffee research hall, happy to share the knowledge about coffee with you, we share unreservedly just to make more friends fall in love with coffee, and there will be three low-discount coffee activities every month. The reason is that Qianjie wants to make more friends drink the best coffee at the lowest price, which has been Qianjie's tenet for 6 years!

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