The quality of espresso: from the barista

Just as coffee beans are essential to the quality of espresso coffee, so is the knowledge and skill of the barista. It doesn't require any high-tech knowledge to make espresso, but there are a lot of necessary knowledge and skills in the process, and there are also some taboos that need to be mastered by baristas.

The first and most important thing is to use high-quality coffee to make, coffee must be fresh. Usually, the roasting degree of Italian coffee is relatively deep, and the blending should also follow the blending principle of Italian coffee. Arabica coffee beans should be the main ingredient in the blending. Coffee is best consumed within 2-10 days of roasting, after which the quality of coffee declines rapidly. Because of this, you should try to buy coffee less at a time and more frequently, such as once a week, to minimize hoarding. The space in which you keep your coffee should be cool, dark, and dry, avoiding refrigeration unless you have to deliberately prolong the drinking time of the batch, or the space in which you usually keep your coffee is too hot (above 80 degrees Fahrenheit) and you have to lower the storage temperature.

Next, you need a well-maintained commercial grade espresso maker. Traditional espresso machines have the ability to make a cup of high-quality espresso coffee, and from this point of view, traditional semi-automatic coffee machines are more capable than fully automatic coffee machines. A fully automated coffee maker that grinds, fills, presses, extracts, and even froths milk at the push of a button is nowhere near as skilled as a barista. It is possible to produce coffee of consistent quality, but the quality of the coffee itself is in the middle to lower levels. If you're looking for quality espresso, this isn't the place to stop.

If you are using a traditional semi-automatic espresso machine, then a high-quality coffee machine grinder is also essential. To see the quality of a coffee grinder, the key is to see the stability of its grinding and the adjustability of its grinding thickness. Sometimes you need to adjust to a very small range to finally get a cup of perfect espresso. So if you haven't purchased a grinder yet, determine the adjustable degree and range of grinding thickness of the grinder you will purchase before purchasing.

Assuming you already have all the equipment and tools to make espresso, the next step is to make the barista's skills very important. Here are a few very important elements that baristas need to understand and master:

First of all, unless you have a line of customers waiting to buy coffee in your store, you only need to grind enough coffee powder at a time. Because the whole coffee bean is like a container with coffee aroma and taste, once the coffee is ground, it is as if the container is broken and loses those precious aromas and flavors.

Make sure that the handle of the coffee refill is warm before making the coffee powder. The handle of the coffee maker should remain screwed onto the brewing head even when it is not making coffee to ensure the handle temperature. Because if the handle is cold, when the hot water flows through, the metal handle will first absorb part of the heat of the hot water, and reduce the water temperature, the low temperature water will cause insufficient extraction, thus making the coffee taste more water, and taste sour.

Then the barista fills the warm handle with ground coffee. Here the barista should ensure that the coffee powder is filled in the same amount each time the coffee is made. Usually baristas fill the coffee powder until it spills, and then wipe off the coffee powder along the edge of the handle to ensure that each fill is equal. If you make sure you fill the same amount each time, all other things being equal, you will produce the same quality coffee for each cup.

Then use a powder hammer to compact the coffee powder. Using a powder hammer for compaction is much better than using the compactor that comes with the bean grinder. In addition, the diameter of the powder hammer surface should be basically the same as the diameter of the handle powder bowl. When pressing, try to ensure that the powder hammer is pressed into the bowl horizontally and evenly (about 40-50 pounds of force). Finally, rotate the hammer to smooth the surface of the cake and make the cake fit better with the edge of the bowl, making the cake and bowl a whole. After the filling is completed, the residual powder around the powder bowl should be cleaned up because the residual powder around the powder bowl will affect the sealing degree after the powder bowl is screwed on, and at the same time, if there is a long-term residual powder, it will also affect the service life of the brewing head seal ring.

After fitting the handle back into the coffee maker, you can begin extraction. Next, you can basically judge whether this cup of coffee is basically qualified by observing the outflow state of the espresso coffee.

After extraction begins, it takes a few seconds for coffee to flow from the diverter spout at the lower end of the handle. If all the ingredients mentioned are correct, the coffee will flow out like a spaghetti, like hot syrup, brown and red, forming a foam layer about 0.25-0.5 inches thick in the cup. In most cases, we limit the extraction time to about 25 seconds, and the total flow rate is about 1 ounce. Sometimes a little less extraction may taste better, so we usually don't extract more than 1.25 ounces.

The foam at the top of the coffee we call "Crema", this is the result of the coffee in the sugar charring, due to the heat and pressure of the formation of a large number of tiny bubbles floating in the top layer of the cup. Thick foam and bronzer color are signs of a good cup of espresso, and getting this result also means that the coffee powder is properly ground.

If the coffee is ground too finely, the espresso will drip rather than a continuous stream, or even no coffee will flow. If you see this phenomenon, then you should reduce your grinding degree to a bit coarser, so that the coffee powder particles are slightly larger. If the coffee is ground too coarsely, the flow rate of water will be greatly accelerated, so that the coffee flows too fast, such coffee generally has a hay taste, and there is no sticky taste, that is, we usually say that the water is relatively watery, and it will be relatively acidic, and the color of Crema is also relatively white. This allows you to extract about 1 ounce of coffee in 10-15 seconds instead of the 25 seconds we require. If that's what you're seeing, you'll need to make your grind a little finer and have smaller particles.

Every time you adjust the grind, you need to turn the grinder on for a few more seconds, and then discard the ground coffee, which is actually what we call residual powder, which is the coffee powder that has been left in the coffee mill before you adjust the grind. After pouring out this part, regrind it again, and the coffee powder will be ground according to the grinding degree you readjust. Adjust the grinding fineness of the bean grinder repeatedly until the appropriate extraction amount is obtained.

After extracting the coffee, knock off the coffee grounds in the powder bowl, then rinse and wipe the handle, and then put the handle back on the coffee maker, so as to ensure that the handle is warm and ready to use.

If you're going to add milk to your espresso drink (which is the staple of most coffee shops), you'll also need to make foam next. Good foam should look dense, with a bright surface that hangs on the surface of the milk tank without obvious bubbles. And many times, many baristas make milk bubbles like soapy water or whipped egg whites, with obvious bubbles, which are completely unqualified. Good foam can improve the overall taste of the drink, drink like velvet smooth consistency.

To make high-quality foam, cold milk should be used. Add milk to 1/3 of the milk tank. Next, open the steam pipe and let it empty, allowing the water vapor remaining in the pipe to escape. Now you can hold the milk jar and immerse the steam tip completely into the milk. The milk tank is about 20-30 degrees from your body. The steam pipe is leaning down against the side of the tank wall. When the steam is turned on, the blown steam should be able to blow the milk along the tank wall.

After the milk tank is in place and the steam pipe is in place, directly turn the steam to the maximum gear, and the milk will rotate in one direction with the steam in the milk tank. At this point, one of your hands holds the handle of the milk tank and the other hand holds the bottom of the milk tank. Your hand will act as a thermometer. At this point, keep the steam pipe still and carefully lower the milk tank until the head of the steam pipe touches the surface of the milk slightly. You can tell the position of the steam pipe head by sound. As soon as the tip of the steam pipe comes out of the milk, you can hear the "sizzling" sound, which is the correct sound. If you hear the sound of "purr, purr", the milk tank is too low, and the steam pipe is full of milk, so that the milk will form thick milk bubbles. Keep the steam tip as close as possible to the surface of the milk as it goes through the process until your hand feels a little warm at the bottom of the milk tank, which is about 100 degrees Fahrenheit and should be enough foam.

Between this point and heating the milk to 140 degrees Fahrenheit, the milk doesn't need to be cooled. Raise the tank slightly and insert the steam tip into the milk so you don't hear the sizzling sound. Then let the milk continue to spin and heat, and when you feel the milk reaching 120-130 degrees Fahrenheit, quickly turn off the steam (at this point, the actual temperature of the milk should be 140-150 degrees Fahrenheit, because the temperature sensor speed of the human hand is basically a few seconds later than the actual temperature, so basically your brain reflects the temperature of 120-130, almost the actual temperature is 140-150).

An experienced and skilled barista can judge the temperature of milk by hand and thus decide when to turn off steam. Every barista probably has his own timing method or trick, but if you don't have one, try this: heat the milk with steam until your hand feels a little hot at the bottom of the milk tank, then count to yourself slowly "1, 2, 3" and immediately turn off the steam. At this time, you measure the temperature with a thermometer. If the temperature is less than 140 degrees, you can count several numbers until it reaches 140 degrees.

Throughout the whipping process, the milk rotates in one direction, forming a dense foam that eventually forms the texture you want. It doesn't matter if you don't create large bubbles during the whipping process. You can let the steam pipe tip slightly expose the milk surface and drag the large bubbles down into dense fine bubbles. When you're done, rotate the milk jar a bit, like shaking a wine bottle, to mix the milk and foam evenly. As soon as possible into the good foam coffee drink.

Finally, wipe the end of the steam pipe with a wet towel and let steam flow again to ensure that the milk sucked back into the steam pipe is discharged. If you don't take good care of your equipment, the machine that once made great coffee may soon not be able to make the original flavor. Your coffee maker should be backflushed daily, and the handle and powder bowl should be soaked overnight after use to remove all residue. Coffee grinders need to be removed weekly for cleaning and wiping, and powder bins should also be removed for thorough cleaning to ensure residual coffee grease is removed. the brewing head

The rubber seal on the grinder should also be replaced if leaks are found, and the sharpener should be replaced every time about 500 pounds of beans are ground. Believe that every effort and penny you spend on maintaining your equipment is worth it.

Once your barista is able to make consistent espresso and produce the required foam, they can move on to the next stage, learning to pull coffee. Coffee flopping can make your barista look more professional than the average barista, and it can also make them feel that their work is interesting and make them proud of their work. And the most important thing is that the beautiful graphics verify that they are doing everything else correctly, because if you can't make a good cup of espresso, you can't make perfect foam, they can't make beautiful coffee.