Coffee Science: the Flavor Source and volatility of Coffee

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In a broad sense, taste includes the signals transmitted to the cerebral cortex by the five senses (vision, hearing, smell, taste and touch), which are processed by the central nervous system, so our five senses are the medium of taste signals; but in a narrow sense, we usually think of taste as "feedback from the nasal cavity and taste buds to the taste of food". The reason why we can feel so much flavor from coffee is because of the existence of aroma substances. These aroma substances have one thing in common-they are volatile.

The aroma we smell belongs to the aroma substances of coffee, most of which are volatile, so we can feel them with our sense of smell, while some of them are volatile and water-soluble, which can be felt by smell and taste; a small number of them are water-soluble and can only be felt by taste.

Some sweet and sour flavor molecules are volatile and water-soluble, so both smell and taste can be enjoyed, but the unpleasant bitter and salty taste is water-soluble and non-volatile, which can only be felt by taste.

There are many factors that affect coffee flavor: coffee bean varieties, roasting conditions, brewing strategies, coffee bean treatment methods. However, when you divide these factors again and again, in the end, the flavor of coffee depends on one kind of substance-- compounds.

These compounds are affected by the way coffee is roasted, the type of beans, and the altitude at which coffee grows. But if you want to really optimize the flavor of coffee, you need to understand the science behind it. This is especially true for bean bakers, whose job is to control several key chemical reactions by changing calories. )

I am currently studying for a doctorate in food science, and my major is to predict the flavor, aroma and quality of coffee by analyzing its chemical composition. Next, let's take a look at the main points that you and I should grasp.

Flavor: it has something to do with chemistry

Aroma, flavor, aftertaste, acidity and alcohol thickness-all five properties correspond to different compounds. On the cup table, we interpret them with our senses-even then, the chemical reaction is still going on. We evaluate the dried incense, followed by the aroma of broken dregs, and then the taste. Different stages, different chemical molecules.

I like to measure the perceptual process of coffee, while paying attention to a variety of compounds in coffee and their interactions. From carbohydrates to caffeine, there are many non-volatile compounds that affect flavor and quality. The proportion of these compounds varies depending on the quality of raw coffee beans-but keep in mind that the chemical composition of raw coffee beans is completely different from that of ripe coffee beans.

At the same time, it has to be mentioned that those volatile compounds, most of which are the products of chemical reactions that take place during baking, have a vital impact on the quality of coffee.