Why does your hand make coffee so bad? The thickness and water temperature of hand coffee powder are the most important!

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Many people are used to buying coffee beans directly from a coffee shop, only to find that they rush out of the taste of the coffee shop when they brew it. Obviously they are the same coffee beans, why is the hand-brewed coffee made by myself not good?

The purpose of extracting hand-brewed coffee is not only to extract its inherent taste, but also to adjust the taste freely according to individual taste and personality. The pleasure of extracting coffee is to extract a variety of flavors freely in this way. So what factors affect the taste of hand-brewed coffee?

Time and concentration of ➤ extraction

When extracting coffee, the initial extract is very strong, and the later, the lighter the color of the extract becomes. This means that the soluble content of coffee will gradually decrease. The dissolution of coffee ingredients is not a uniform concentration as we think, but a process from concentration to dilution.

Coffee is a liquid in which the coffee ingredients formed in the roasting process are dissolved by water, and the taste of the coffee varies with the concentration of the coffee ingredients. In the early extraction, the aroma and flavor are strong, and the concentration is also very high. The later the extract, the taste and aroma will fade. In the early stage, about 20% of the extraction solution dissolved about 80% of the total coffee. In other words, the early extract will maximize the dissolution of coffee components, thus playing a role in determining the taste and aroma of coffee. The woody components that form the structure of coffee beans are dissolved in the extract in the later stage, and there are many components that determine the thickness and bitterness of alcohol.

Every stage of tasting coffee

Color of coffee extraction solution at each stage (early ➙ and later stage)

The coffee liquid extracted in the early stage is mixed with water, the taste is lighter and softer, and the aroma is charming, but it lacks thickness and personality. If the late extract is properly added to the early extract, it can make up for the bitterness, highlight the aroma and taste, and emphasize the thickness and personality. The aroma and taste of coffee extracted in the early and later stages are different, which can be used to adjust a more delicate and personalized taste.

Utilization of water injection point

Good coffee ingredients are mainly extracted in the early stage, because before the end of the extraction, first inject a small amount of water to maximize the extraction of good coffee ingredients. Then wait until full dripping before injecting water, so that the diffusion of coffee will be more active, resulting in a strong flavor of coffee extract.

In order to restrain the taste of coffee, a relatively faster extraction rate was used in the later stage than in the earlier stage. The amount of water injection in the later stage is more than that in the early stage, so the extraction speed is relatively faster and the extraction liquid is relatively light. In addition, in the later stage, do not wait until after all the dripping before replenishing the water injection, when the amount of dripping water is small, replenish the water injection immediately, so that you can get a lighter extract. If extracted in this way, water can be injected more than 4 times.

If this kind of extraction method is not skilled, the amount of water injected, the number of times and the time point of extraction will be different, so the taste of extraction is also different. If only individuals enjoy coffee, this will not be a problem, but in coffee shops, it is difficult to reproduce the same taste.

The thickness of ➤ coffee powder

This is directly related to the surface area of coffee cells that come into contact with water. For a simple example, let's first compare the dissolution rate of large-grained salt with that of fine salt. We can obviously see that the salt ground into fine powder dissolves faster than large salt, because after grinding into fine powder, the surface area of salt in contact with water is large, and the melting rate is faster.

The same is true of coffee, coffee powder is ground fine, the surface area of contact with water is large, and the concentration of dissolved coffee ingredients is also high. On the contrary, when the coffee powder is ground coarsely, the surface area of the coffee powder in contact with water is less, and the concentration of the extract is also low.

Confirming the apparatus for crushing particles-- Test sieve (test sieve)

Made of barbed wire, usually called mesh

Can I grind the coffee powder as finely as possible?

The finer the coffee powder is ground, the more fine it will be. this fine powder can easily block the holes of the filter paper, making it difficult for water to pass through the filter paper. In this way, the extraction speed of coffee becomes slower, and the time for natural coffee to be soaked becomes longer, and the miscellaneous flavor extracted with it is also greater.

When extracting Italian concentration, the general coffee powder is ground very fine, which can be extracted in a short time to maximize the aroma and taste of coffee. Because the concentrated coffee powder is too fine, it is impossible for water to pass through the coffee powder with natural gravity, so the pressure of 9Pa is artificially added to make the water pass quickly between the coffee powder particles to moderately extract the aroma and flavor. Hand punching is different, can not add water pressure to adjust the extraction speed, can only adjust the extraction speed according to the thickness of coffee powder.

For example, the coarse powder of 0.85mm accounts for about 70% of the whole, which is generally recognized as the ideal thickness of hand punching, but it is difficult to accurately reach this thickness in practice. So usually grind to the size of half a grain to the size of a sesame seed to find out the concentration and flavor of the coffee you want.

Temperature of ➤ water

Another important factor in regulating aroma, taste and concentration when extracting coffee is the temperature of the water.

Comparing the speed of dissolving white sugar with hot water and cold water, it is obvious that hot water melts faster than cold water. The same is true of coffee, the higher the water temperature, the more aroma and taste of coffee dissolve out, its taste is also very strong and bitter taste also increases.

On the contrary, when the temperature of the water is low, the aroma and taste of the coffee are weak, and the bitter taste of the coffee is weak.

The most suitable temperature for the extraction of coffee is 90-℃-92. If the temperature is higher than this, some of the ingredients in coffee (such as caffeine) change due to high temperature, bitter taste, and scorched taste.

Although the temperature of 90Mel 92 ℃ is the most suitable temperature for coffee extraction, it is not necessary to extract coffee at this temperature. From the extraction to the end, if the water temperature is always maintained at 92 ℃, both good and bad flavors may be extracted to the maximum extent at the same time. Therefore, you can adjust the water temperature to extract your favorite coffee.

① adjusts water temperature according to extraction time

When determining the water temperature, the extraction time should be considered first. If the extraction time is short, the water temperature is relatively high; on the contrary, if the extraction time is long, the water temperature is relatively low. The short extraction time means that it takes a relatively short time to extract the bad taste and miscellaneous flavor from the coffee. Therefore, high temperature extraction will not dissolve a lot of odor. On the contrary, the time to soak out miscellaneous flavor is relatively sufficient, and the bad taste such as bitterness and wood taste is very obvious. Therefore, the first thing to consider before determining the water temperature is personal preference and extraction time. According to the extraction time, it can be changed freely at 80 ℃.

② adjusts the water temperature according to the material of the hand pot.

The water temperature can be adjusted according to the different materials of the hand-flushing pot. For example, the copper hand punch pot has good thermal conductivity, and the water will soon cool down. When using copper hand pot extraction, the first coffee is extracted at a very high temperature, its aroma and taste are very strong, and later extracted with a relatively low water temperature, so this part of the extracted coffee taste is relatively light. The strong extraction part in the early stage and the relatively weak extraction part in the later stage are mixed together, the aroma and taste are good, the bitterness and miscellaneous taste are less, and the taste of coffee is relatively soft.

③ adjusts water temperature according to coffee freshness

When water is injected into the coffee, the hot water will seep into the porous coffee cells and squeeze out the gas produced during baking. The fresher the coffee beans, the more gas they produce when roasting. To extract such fresh beans, you can generally choose a lower water temperature. And for fresh coffee beans, the oil inside the cells has not yet seeped into the porous cell tissue formed during baking, so the coffee will be fully extracted. Therefore, the extraction of fresh coffee beans will choose 80 Murray 86 ℃ of the lower water temperature.

For coffee beans that have been kept for a long time, the gas has been discharged naturally, and the coffee oil is filled with porous cell structure, so the coffee can not be fully extracted. In this case, the coffee can be extracted at a relatively high water temperature of 84Mel 90 ℃.

➤ adjusts the amount of coffee

When extracting coffee, generally use 10g coffee powder for 1 cup (120mL), and add 8g more for each additional cup. In this way, with each increase of 1 cup, the ratio of coffee powder changes because of the shape of the filter cup. The filter cup is shaped like a funnel, and even with the addition of 10g coffee powder, the area of expanded coffee (round shape) cannot be doubled. So appropriately reducing the amount of coffee can also meet the concentration of coffee.

List of the ratio of extracted hand-brewed coffee

According to the standard of SCAA, when the extraction ratio of hot water dissolved into the filter cup of coffee reaches 18% Mel-22%, it can be regarded as the ideal concentration of coffee extraction. According to this reasoning, in order to extract 1L of coffee, the optimal concentration can be extracted by using 50Murray 60g coffee powder (1.15% Murray 1.35%).

If you want to extract 1L of coffee, such as using 40g coffee powder, according to the best coffee extraction ratio of 18% Murray 22%, its concentration is 0.8% Murray 0.95%, it will feel very light. If you adjust the fineness of coffee or extend the extraction time to meet the concentration of coffee, it is easy to cause excessive extraction, and its taste can not be guaranteed. So if you want to get the right coffee concentration, you need to adjust the amount of coffee powder. Generally, in order to meet the ideal concentration, 55murmur65g coffee powder is needed. In other words, extract 1 cup (120mL) of coffee using 6 Murray 8g.

But the standard of particle thickness under this condition is 0.85mm. If it is a little thicker than this standard, the extraction ratio and concentration will decrease, so it is necessary to add a little more coffee powder when the particles are coarse. On the contrary, if it is a little finer than the standard, the extraction ratio and concentration will increase, and then the amount of coffee powder can be fine-tuned. In addition, when the amount of one-time extraction is more, in order to avoid excessive extraction, the amount of coffee powder can be reduced a little bit.

If we want to apply the ideal values of these standards to coffee extraction, we should not only consider the values, but also consider various variables and respond flexibly to changes in conditions. In addition, in the final evaluation, what is more important than achieving the target value is whether the sensory evaluation is good coffee. Here we have to keep in mind that many opinion polls have found that even if it is beyond the ideal range of extraction (strong or weak), many people will like it.

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