What is the reason why the temperature of coffee extracted by coffee machine is too low?

What is the reason why the temperature of coffee extracted by coffee machine is too low?

1. The amount of powder [should describe the ratio of powder to water, that is, the ratio of coffee powder to extracted coffee. But to be frank, there is only one variable]: the change in the amount of powder determines the number of substances that can be involved in the extraction. The amount of powder is directly proportional to the concentration and inversely proportional to the extraction rate. With the increase of the amount of powder, more substances can be involved in the extraction, reducing the amount of wood flavor extracted repeatedly by unit water per unit powder.

two。 Degree of grinding: the change of the degree of grinding directly affects the particle size and surface area of the unit powder. The finer the particle is, the easier it is for water to extract with the powder [inappropriate example: diced meat is easier to cook than the whole piece]. The higher the extraction efficiency [extraction efficiency and extraction rate are two completely different concepts].

3. Time: with the extension of time, the extraction rate becomes higher and higher until 30% stops.

4. Water temperature: the water temperature is positively correlated with the extraction efficiency and has little effect on the concentration.

In the case of the water temperature, grinding degree and other conditions basically unchanged, the amount of powder decreased, I, as a barista, made adjustments to the coffee produced.

Let's first take a look at the situation of stress reduction in 2bar. In fact, the most direct result of stress reduction is Crema. I used Bilody's first-generation mocha pot at home before, but in order to get a better Crema, I modified it to be closer to Bilody's third-generation double-valve door pot, which is commonly known as the extra-thick pot. It is precisely because of the experience of refitting the mocha pot that I am not surprised by the failure and maintenance results of the coffee machine. For Italian matching, the reduced Crema is acceptable because the grease in our mix itself is thicker.

Let's look at the situation of reducing the amount of powder by 2g. The decrease of the amount of powder is bound to result in excessive flow rate, insufficient extraction and so on. I didn't adjust the degree of grinding too much because I didn't want to introduce the third variable parameter, so I adjusted the extraction process. First of all, our machine does not have the function of pre-soaking. I manually control the switch, put in hot water without coffee, and do manual pre-soaking for about 2-3 seconds, and then change the normal ESP into 45ML long-shot to improve the extraction degree. I have tried 5 seconds of pre-soaking, the guest response is too bitter, but also tried not to pre-soak, the guest response is tasteless, 2-3 seconds is just right. I have always thought that the knowledge of coffee is versatile, and the above changes stem from my understanding of pre-soaking and hand steaming. The first coffee machine I came into contact with was the Conti X-One, and I often made changes to steaming instead of dogmatic 30 seconds when I was hand-brewing.

I have adjusted the grinding degree of the powder, become finer, the amount of powder is the same as before, not pre-soaked, light filling pressure, due to pressure, extraction time is too slow, not often uneven extraction phenomenon, but the taste can still be accepted, because most of the guests can not drink, and finally out of the parameter control and quality control of the difficulty coefficient, did not do so.

In order to ensure that the taste of the coffee is basically the same as the original, American products correspondingly reduce the amount of water about 1oz, so that it will not appear lighter, that is, the American style of the 12oz cup is no longer a full cup. When making lattes and cabs, we deliberately thickened some milk foams, which increased the foaming volume by 5-10%, reducing the fluidity of milk, in order to increase the initial surface oil saturation caused by thinned Cream during fusion, because I found that the Crema extracted from coffee and the fat in milk are oils, which is an important part of the taste of milk coffee. In the case of a foreigner ordering ESP, it is still normal shot, without long-shot. I know very well that this taste must be wrong, but I can only do it brazenly. After all, I open the door to do business. Alas, I can see the look of the boss behind me.