How does the bitterness of coffee beans come from? what are the characteristics of the nutty flavor of coffee beans?

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The non-producing areas of fine coffee in Africa are divided into Ethiopia, Kenya and Yemen.

Today I happen to be able to drink coffee from African countries and share my feelings about the taste.

1 Sun Jega (shallow baking): dry incense has a strong and distinct blueberry aroma. It tastes mixed, light floral, blueberry and sour.

2 washed Yega (shallow baking): dry fragrant flowers, no blueberry fragrance. Taste more aroma, strong sour taste for citrus, clear and no miscellaneous smell.

3 Kenyan AB (shallow baking): dried incense is woody and nutty with a sweet taste. Taste very sour, for citric acid to add some bitterness, like lemon peel taste, acceptance should not be high.

4 Kenyan AB (deep baking): no acid, no bitterness, cocoa taste. High acceptance.

5 Luanda (shallow baking): dry incense is mixed with woody nuts. Taste bright sour, light blueberry flavor.

6 Tanshania (shallow baking): dried incense is mixed with woody nuts. Citric acid tastes bitter, much like Kenya, but the mellow finish is thin.

7 you can choose coffee to drink according to your favorite / acceptable acidity, sweetness, and flavor intensity. So, there is a strange place here, why didn't I list the bitterness?! Because most of the bitterness comes from baking. What? Believe me! Roasting can greatly affect the sour, bitter, and native flavor of a coffee, so what is the relationship between them? Please see the following figure:

Be careful! This chart is an absolute trend, that is to say, all coffee beans apply!

● Fruit Acid: as the baking progresses, it begins to produce fruit acid. After a certain stage, there will be less and less.

● bitterness: there will be more and more, dear, life is already bitter enough, let's stay away from the sea of bitterness!

● flavor of origin: please note that it may be good or bad, depending on how coffee beans are produced in the place of origin. Does the owner of the farm take good care of it? if so, it may have a good flavor. If not, it will give it a defective and uncomfortable flavor, so the coffee beans will be felt by us when they are lightly roasted, which is why most coffee chains that use low-quality cheap coffee beans roast the beans so deeply. ♢ 's new flavor ♢ brings "baking aroma". What about the changes inside the coffee beans?

Two main chemical reactions are involved: (1) Mena reaction / Maillard Reaction (2) caramelization / Caramelisation. Both reactions produce a dark pigment, which covers the coffee with a layer of gray. Ah, no, it is darker and darker.

Mena reaction | Maillard Reaction what is the Mena reaction, please see the following figure:

Is it suddenly enlightened? So these are the Mena reactions, and yes, the Mena reaction requires two very important raw materials: protein, and reducing sugar (reducing sugar). A chemical reaction requires energy, or a reaction enzyme, to help the reaction, and the Mena reaction is a chemical reaction that does not require a reaction enzyme. What it needs is heat, and the initial temperature is about 150C. Will produce extremely complex aroma molecules, nuts, butter, baked biscuits, toast, spicy aroma, all belong to the Mayna reaction.

Caramelization reaction | Caramelisation when the temperature continues to rise, all sugars begin to caramelize. Caramelization is a chemical reaction that is poorly understood, except that it produces complex chemical molecules that produce colors and aromas of caramel, vanilla and nuts. However, if the temperature continues to rise, all these smells will be destroyed and eventually wobble! Of course! None! Save! Only bitter, smoky, and pungent chemicals are left.

Is it spicy? do all coffee beans produce the aroma of Mena reaction and caramelization? The answer is yes, as long as there are protein and reducing sugar in raw coffee beans. But depending on the content of raw bean protein and reducing sugar, the more the content, the more aromatic substances can be produced, and what kind of raw beans will have more sugar and protein? In a word, Arabica coffee beans grown in the mountains.

Speaking of this, do you have a certain understanding of the relationship between the degree of baking and flavor? How to choose the coffee that can drink the flavor value of the place of origin? First of all, please choose light baking, that is, the surface with some wrinkles, no glossy, light brown color. Do you guys know like this?

You don't understand the 📒 of baked beans, do you? Deep baking will reduce fruit acid, increase bitterness, reduce the native flavor Mena reaction / Maillard Reaction: when the baking temperature reaches about 150C, it will produce aromas such as nut, butter, biscuits, toast, etc. / Caramelisation: color and aromas such as caramel, vanilla and nuts will be produced when the baking temperature is higher than 180C. Arabica coffee beans in the mountains have more protein and sugar content and produce up to 800 kinds of aromatic substances during baking.

Kenya is suitable for deep baking with high acceptance.