Coffee roasting awakens the strongest aroma in the world

The small, high-altitude raw Arabica coffee beans are like a warehouse full of chemical snails. today, scientists have identified more than 2, 000 known ingredients, of which 7 to 850 are aromatic ingredients, which can be called the most confusing fragrance in the human diet. There are only 150 kinds of fragrant herbs used for seasoning in the catering industry, and the mellow fragrant ingredients of wine are not nearly as rich as coffee.

Baking wakes up the fragrant genie

However, the 700 to 800 kinds of fragrance "elves" in raw coffee beans will not come out on their own, but must be "woken up" by professional baking. without this procedure, coffee can only be tasted in the sun or washed in water, and it smells unpleasant, let alone drink it. The raw beans were heated for five to 25 minutes. (note: the baking equipment of the two schools of quick-fried pie and slow-fried school is different, and the time required is not the same, which will be described later.) the chemical composition of raw beans has changed dramatically, thus revealing a strong fragrance rarely seen in the world. this complex chemical spinning hook cannot be simulated even in the most careful laboratory today, but it can be summarized into a few important items.

First of all, when raw beans are baked at more than 200 degrees Celsius, the water evaporates at intervals, the volume expands by 60%, and the weight is reduced by 10% to 25. Depending on the baking level, the deeper the baking, the more weight loss is lost. No wonder many people do not like re-baking to save costs. Another major phenomenon is exhaust. Raw beans will continue to exhaust after baking ⑴ carbon dioxide for 30 days after baking. Interestingly, the emission of carbon dioxide contributes to the preservation of coffee beans, because the oxygen molecules are not easy to invade during the exhaust process, that is to say, the oxidation and dyeing of damaged coffee flavor cannot be carried out, but the exhaust phenomenon of roasting Qihehan gradually slows down. Oxygen molecules are easy to rely on the bean surface, and the flavor of coffee decays quickly, which is the main reason why coffee beans are best used up within a week after opening.

Baking tips: get the highest caramel and minimum carbonization

Caramelization is a link that has the greatest impact on the flavor of coffee. After baking for six to seven minutes, raw beans receive a large amount of heat and start pyrolysis spinning hooks, showing the first explosive sound. Some sugars are converted into carbon dioxide, and water continues to evaporate. New aromatic components gradually grow out, forming the so-called coffee oil. It is connected with hundreds of aromatic substances such as nicotinic acid, citric acid, quinic acid, malic acid, acetic acid, caffeine and so on. Pyrolytic spinning hook can continue to the second explosion, although caramelization is the main process to wake up fragrant elves, but with the baking time lengthening, some ingredients will also be carbonized missing, forming poor astringent substances, how to get the highest caramelization, but also to minimize carbonization, seemingly contradictory is the biggest challenge for bakers.

Pay attention to the change of sound, color and taste

The above chemical spinning hook can judge the level of isolation line by listening to sound, seeing color and smelling smell when baking. The color of coffee beans will continue to heat up, from gray to golden brown to light brown, and then to a trace of reddish brown out of oil, and then a large amount of oil is dark brown. If you bake it again, the coffee oil on the bean surface dries and appears dead black. And emit a large amount of blue smoke, with a scorched smell, this is a warning close to the ignition, prepare to play 119 to assist in extinguishing the fire. Experienced bakers choose from light brown to oily dark brown for safety. Coffee beans change from shallow to deep because of caramelization and acid transformation. Listening to sound is also the basis for determining the degree of baking. If the temperature of the roaster is hot enough, the coffee beans will make two bursting sounds during the baking process. Take the high-temperature-resistant raw beans such as Mantenin and Angelica as an example, the first explosion will be made in seven minutes, and the sound will be low and sparse. This implies that the "pyrolysis" has started, that is, the starch begins to turn into caramel, and the water also spurts out the bean table with carbon dioxide, giving a low burst sound for two minutes to be comfortable. Twelve minutes around and made a more vicious and sharp burst sound, which is the sound of coffee bean cell fiber breaking, which indicates that the baking is coming to an end, and then the fragrance will fade. It can be seen that coffee beans can be worded. In addition, Brazil and Java and other less heat-resistant beans, the first and second explosion came earlier, heat control is particularly expected.

Define the baking degree by data

Appreciate the "virtue" of coffee beans when roasting, and then talk about the definition of various roasting degrees and the problems of mouth and stomach. In the United States, Cinnamon (shallow roasting), City (shallow roasting), FullyCity (deep roasting) and Darkroast (heavy deep roasting) have long been used to define the roasting level. however, the preference for coffee flavor is that of shallow roasting on the west coast and may have reached the deep roasting level of the east coast, and vice versa, so these terms still belong to their own tunes and are not scientific. In recent years, the American Fine Coffee Association has strongly advocated the caramelization value (Agtronnumber) to determine the baking degree, and the red inner line is used to determine the caramelization level of coffee beans. The higher the value, the lower the caramelization, that is, the shallower the baking degree, and the lower the baking degree, the deeper the caramelization, that is, the deeper the roasting degree, the more accurate the roasting degree of coffee beans, so as not to show that the shallow roasted coffee in the United States and the West has become a joke of re-roasting coffee in the East. This is a good evolution.

Seattle Gourmet Coffee also uses this scientific yardstick to define the degree of roasting. The caramelized number of roasts above 70 is the shallowest roasting, the City,40 above the shallow roasting is Viennese roasting, or the so-called Fullycity,35 below is heavy deep roasting, including French roasting and espresso roasting. The flavor of coffee will also change with different roasting degrees. Generally speaking, sour taste is inversely proportional to roasting degree. If you prefer sour taste, you might as well buy a lighter roasted coffee. If you like a thick, sweet mouth and stomach, you can choose heavy roasted beans. In addition, caffeine content is inversely proportional to roasting degree, that is, light roasted coffee contains more caffeine than re-roasted coffee. Because caffeine can be damaged during baking. The fragrance will also decrease with the deepening of the baking degree, but the fermentation flavor, choking taste and sweet taste of mellow wine, shallow roasted coffee is not easy to grow, re-baked beans have this advantage. However, if you re-bake uncomfortably, you are likely to get a stove of rotten coffee that is scorched and bitter.

Shallow baking and deep baking, noisy!

The fact that coffee should be roasted lightly or deeply is the most controversial topic in the industry, even to the point of falling out. Generally speaking, the baking degree of Northern Italy and the eastern United States is relatively shallow, and the caramelization value is mostly around 40. The famous charms of this school include IllyCaffe, GreenMountain and VivaceEspresso (note: although the company is based in re-baked Seattle, it goes against the trend and advocates shallow roasting), and the coffee beans of these charms cease fire immediately before the second explosion or before the bean table is about to ooze coffee oil. Their argument is that coffee oil contains a large amount of fragrant ingredients, which should be retained in beans as far as possible. Coffee oil seeps out. Although the oil is fake, the fragrant components are also lost. This pie also believes that the coffee beans are baked immediately before the oil comes out, the caramelization level is the best, the Body (consistency) is also the best, and the coffee has the most balanced sour taste and sweet taste. Shallow roasting pie also retaliates against those who re-bake coffee oil out of the bean surface. However, re-baked pies from southern Italy and the west coast of the United States, such as Peet'sCoffe in San Francisco and Caffe'D' in Seattle Arte), and Coffee beans and Machinery Company (BeansandMachines), however, insist that coffee beans must be roasted out of oil in order to taste good. Their beans have been tested to have caramelized values of less than 35 for espresso, and the sour Andi guar has even been overbaked at 18 degrees, which is really to the point of "heavy baking without soft hands."

Most of this pie glided for a while after the second explosion or the appearance of the bean oil. They did not agree with the saying of the shallow baking pie that "to produce oil is to lose the fragrance," and criticized the beans of the shallow baking pie for "incomplete growth." the sharp sour taste seems to outweigh the sweet taste and poor the choking taste, and the flavor is too monotonous. They even ridicule that the real purpose of shallow baking pie is to save money, because only top Arabica beans can withstand heavy baking and grow into a rich, choking, sweet and non-biting flavor, while secondary beans suffer from the fire. Will only show a monotonous bitter taste.

The heavy baking pie also boasts that it is a "glutton coffee that walks the edge of the razor." because the coffee beans change quickly after the second explosion, the whole furnace is slightly missing and reimbursed in the city, unlike the shallow baking pie, which "withdraws its troops" before the oil burst, and its craftsmanship is relatively low. Bitz Coffee, which advocates re-roasting, enjoys a noble status in the coffee industry in the United States. Bitz can produce beans at a high temperature of more than 200 degrees Celsius, operating the oven for more than 15 minutes, and it is strong but not bitter, which is admirable. Of course, this has something to do with Bitz's ability to refit the roaster. In short, the heavy baking pie insists that only the beans after the second explosion, the flavor is complete.

To be fair, light roasting and deep roasting have their own advantages. Drinking coffee already has a strong unaesthetic nature and should respect each other. Fortunately, the dispute in the coffee industry in Taiwan is not as obvious as that in the United States.

Stir-fry quickly, slowly, each has its own insistence.

In addition to the degree of baking, even the roaster also has a family view. At present, there are two professional roasters, one is the traditional rolling furnace (DrumRoaster), and the other is the newly rising hot gas furnace (HotAirRoaster). The former uses gas to heat the beans across the bottom of the furnace, and the metal blades in the furnace keep stirring the beans, while the latter uses high-temperature hot air to bake the beans, because the air flow is so strong that the beans in the furnace keep fluttering, so there is no need for leaves to stir the beans. Roll converter baking beans need to serve the old litigation chief, generally known as slow stew pie, hot gas oven baking beans is faster, belongs to the fast frying pie.

The industry is red-faced over the merits of these two kinds of roasters, and it is also described as a "war between slow stew pie and fast stir-fry pie." slow stew pie prefers the traditional rolling furnace, believing that it should be baked at first with a warm heat, and then slowly add heat after an explosion, so that the water in the beans can be prevented from evaporating too fast, and the damage level of deep dense tissue can be reduced to a minimum. Only by heating step by step can the flavor of coffee beans be fully grown. Those who advocate slow stewing are mostly famous gluttonous coffee, such as Bitz, Vivac, Allegro and coffee bean and machine companies. Their baking time is about eleven to 25 minutes. Interestingly, the scale of slow stir-frying is small, emphasizing a small amount of baking, disdain to win by quantity, rough stir-frying.

Quick fried beans have a strong sour taste, while slow fried beans are more bitter and sweet.

Quick-fried pie likes to use a hot gas stove, thinking that a strong hot air flow has better heat conduction, and beans are heated more evenly, which can achieve the desired baking degree in the shortest time, and greatly reduce the disappearance of coffee oil and cell tissue damage. baking time is mostly within three to fifteen minutes. Because fast frying saves time and less weight flow of coffee beans, you can save money, so most of the people who use hot stoves are large baking companies that win by quantity, and the coffee of Burger King and McDonald's in the United States is mostly made by the hot stove charmer. Generally speaking, fast fried beans taste sour and organized, while slow fried beans suppress the sour taste and drink it with low strength and sweet taste.

The relationship between quick-fried and slow-fried boudoir chlorogenic acid

All plants contain bitter and strong chlorogenic acid "Chlorogenicacids" to counteract insect pests or germs. Coffee raw beans also contain a large amount of chlorogenic acid, which has something to do with the green-blue glow of raw beans, and the content of chlorogenic acid is also proportional to caffeine. Low-altitude Robusta raw beans have more caffeine than high-altitude Arabica beans, and the content of chlorogenic acid is also higher. Studies have shown that Robsta contains 10% chlorogenic acid. While Arabica is only about 6 percent, it is no wonder that Robusta has a bitter taste.

Chlorogenic acid is a kind of organic acid with the highest content in raw beans, and it is also the original culprit that causes the acidity and bitterness of coffee. Fortunately, chlorogenic acid will be damaged in the baking process. More importantly, the level of chlorogenic acid disintegration is inversely proportional to the baking speed, that is to say, the faster the baking, the more chlorogenic acid remains, the slower the roasting, the less the residue. This is enough to explain why quick fried beans drink more tart while slow fried beans have a smoother flavor. The special bean bucket for espresso is suitable for slow frying. If you fry it quickly in a hot stove at 300 to 400 degrees Celsius, it may explode in less than three minutes. However, too much chlorogenic acid will make the espresso sour.

The relationship between baking and high quality acid

In addition to inferior chlorogenic acid, raw beans also contain a lot of high-quality acids, mainly citric acid, malic acid, acetic acid, phosphoric acid and quinic acid, etc., in addition, other organic acids will be born with the disintegration of carbohydrates in the baking process. At present, as many as 34 kinds of organic acids have been determined, of which 15 are volatile. In principle, the ☆ of high quality citric acid, maleic acid, phosphoric acid and acetic acid is high in medium baking, and decreases with heavy baking. Organic acids have a great impact on the flavor of coffee. Interestingly, the pleasantly active acidity of light-roasted coffee is the overall implication of more than 30 organic acids, any one of which will have a poor taste. Coffee roasting is a great science. The age, density, hardness and moisture content of raw beans should be taken into account. Even the relative humidity on the day of roasting, cloudy, sunny, rainy, temperature and wind direction changes should not be ignored. So the baker is not only an artist but also half a scientist!