Do you want to raise Italian beans for Espresso? How long do you keep espresso beans?

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Espresso beans. Do you want beans?

Coffee freshness is one of the hot topics discussed by SCA in recent years. Swiss chemist Samo Smrke proposed the relationship between CO2 content and coffee freshness at SCA annual meeting last year, and the variables affecting CO2 emission. The study shows that baking degree and baking time have a strong influence on the amount of emission gases and the activity of emissions. The deeper the baking, or the shorter the time it takes to reach the target baking degree, the greater and faster the amount of gas emitted in the same time. Therefore, we often find that coffee roasted with lighter roasts and with flatter roasting curves has a longer shelf life.

What effect does too fresh beans have on extraction? In Espresso's experiments, it was easy to see that freshly baked beans often yielded very thick Crema. However, when brewing, the liquid column is thicker and it is easy to bring big bubbles. Although Crema is more, the bubbles are heavy and the taste is worse. For flavor, the extraction rate may be lower than expected due to CO2 hindrance. Some roasted coffee is easy to produce astringency. For some brewing schemes that judge the ratio of powder to liquid by Espresso volume, too fresh beans are more likely to be misleading. Moreover, too much gas Espresso, drink too much easy to burp or fart, the image of the barista has significant damage.

Therefore, the Italian beans used to make espresso coffee also need to grow beans.

On the other hand, beans are not raised indefinitely. stale beans, CO2 emissions, volatile aroma has also been dissipated. Crema is difficult to extract when extracting Espresso. The flavor is also poor, and even a little sour smell.

Deep roast beans are even worse when they are aged. I believe most coffee lovers have smelled coffee beans that have been put on the supermarket shelf for oil, or the oily smell of deep roast coffee beans stored for too long. This is definitely not a pleasant taste. If someone tries to put such beans in your grinder, stop them. Oxidized coffee grease on the cutter plate may affect the flavor of your subsequent brewing rounds.

Although the one-way exhaust valve can avoid the coffee exhaust to burst the packaging bag, it can also avoid the odor in the preservation environment from flowing into the coffee flavor. However, for the preservation of cooked beans, it is not necessarily the only option. Such as illy, filling tin cans with nitrogen to prolong shelf life. Sometimes we can also tape the one-way exhaust valve to adjust the rate of carbon dioxide emission. Let coffee ripen slowly without losing freshness.

Why beans? For how long?

You've all heard of beans, right? Do not brew freshly baked coffee directly. Store it in a cool, dry space for a few days before it tastes good. In fact, there are many reasons for raising beans, various theories and theories are not ready, but mainstream baristas agree that the chemical changes of freshly roasted coffee beans are intense, which is easy to cause uncertainty and variation in brewing, so raising beans is an inevitable process.

Coffee loses a lot of water during roasting, and at the same time coffee expands its cell walls due to the influence of high temperatures, so that roasted ripe beans have a lot more pores than raw beans, and these pores store a lot of gas. The key point of bean cultivation is to restore the relaxation pressure of the internal fibers of the bean body to be consistent with the room pressure, so the time of bean cultivation is related to the baking degree, and also related to the baking method (ROR temperature curve). These variables will cause different states of the internal fibers. Common bean cultivation time will shorten the date of bean cultivation from light to deep baking degree, which is related to the degree of vigorous exhaust gas.

Of course, the extraction method is also one of the qualities we must refer to. In general, baristas will use pressure extraction/non-pressure extraction as a basis for reference, because in the pressure extraction of Espresso environment, CO2 is more soluble in coffee liquid, we drink crema is composed of aromatic substances, fat-soluble substances and CO2 formed by the golden foam. In normal Espresso extraction, there is no "stewing" operation similar to hand-brewed coffee, and the amount of CO2 has a particularly obvious effect on pressure extraction. Excessive CO2 will not only hinder the contact between hot water and coffee powder, thus reducing the extraction rate, but also increase the probability of perforation (channel effect). Therefore, the Italian beans used to make Espresso usually take longer to grow than the coffee beans used for hand-brewed coffee. For example, the medium-baked Italian beans used by Xiaobian will last for about 10 days. If they are hand-brewed, they can be brewed in 4-7 days.

How long exactly do you need to keep your Italian beans? It's best to ask the baker who sold you beans. Raising beans is a devil's detail, but it is also a knowledge worth exploring. Raising beans must be discussed in every case before it is meaningful, because coffee has so many variables that it can only be said that it is impossible to see the forest for the trees. The final suggestion is that when your brewing skills tend to stabilize, or use simple brewing methods such as cup test and smart filter cup, you can reduce the impact of brewing. After stabilizing brewing factors, you can more accurately understand the causal relationship between bean cultivation and coffee flavor.

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