Hand-poured coffee | How to brew a good cup of coffee with V60 (in-depth article)

How to brew a good cup of coffee with the V60

1. Introduction

I have been interested in specialty coffee for a few years now, using a V60 and hand-cranked grinder to brew fresh coffee beans. I didn't actually read much about how to make a good cup of coffee; I just bought some good coffee beans and read some reviews online about how to brew a good cup of coffee. A few months ago, I decided to do a deeper dive into this and read as many books on the subject as I could.

I began to realize that coffee brewing is a rabbit hole .

Over the past few months, I've changed a lot of my perspectives on brewing coffee. Brewing a great cup of coffee certainly requires good coffee beans , but I've learned that no matter how good the quality of the beans, there are other factors that can completely ruin your cup of coffee. Over the past few months, I've done a lot of experimenting, made a lot of mistakes, and spent a lot of time figuring it out. Therefore, I decided to write an article to distill some of the information and guide any interested readers to improve their coffee brewing process and brew a great cup of coffee whether at home or when traveling.

Another thing that really frustrates me when researching this topic is the degree to which people in specialty coffee are influenced by pseudoscience . Surprisingly, some of this pseudoscience comes from some champion baristas.

This article is not a guide on how to use the V60 - there are plenty of videos on the internet for that. Instead, this article is designed for geeks who are interested in the technical details. I fully realize that some of the techniques I discuss here may only slightly improve the quality of your brew (e.g., "use a 350μm mesh screen to remove 5 grams of fines to achieve a tighter coffee particle distribution"), but some of the techniques discussed, as crazy as they sound, can significantly affect the quality of your brew (e.g., brewing water with 200 ppm total alkalinity).

If you think that using scientific thinking and sophisticated tools to improve brewed coffee is a stretch, I would point out that many other products we consume have gone through a lot of technical evaluations before we learned more about the science behind them (e.g., wine, beer, cheese, Scotch). Somehow, coffee has almost never gone through this. I don't know why, but it may be that people only care about the caffeine in coffee and not the taste of the coffee.

For now, I'll focus on the V60 because it's cheaper, simpler, and easier to carry around. A conical filter cup, usually made of plastic or ceramic, used for hand brewing coffee.

2. Penetration and immersion

Brewing coffee with the V60 involves the concept of percolation brewing . Other brewing devices related to this include batch brewers and moka pots. Percolation brewing contrasts with immersion brewing, in which the coffee grounds remain in contact with the water at all times (a fixed amount of water is poured into the coffee machine once, and no new water is added during the brewing process). Some examples of immersion brewing include the French press and the siphon pot.

The main difference between percolation and immersion. In immersion brewing, as the concentration of coffee increases, the extraction rate will decrease , but in percolation brewing (constantly adding new water/fresh water) the coffee grounds are constantly exposed to the newly injected water, so the extraction rate does not decrease . Both brewing methods can achieve similar brewing results, but the brewing recipe must be adjusted. These two brewing methods have their own special features.

3. Why use V60

Some of you might ask, “If I have a great batch brewer at home, what’s the point of using a V60?” I think it’s possible to brew great coffee with a quality batch brewer (and coffee experts like Scott Rao do it), but personally, I don’t often taste coffee from a batch brewer.

In theory, I don't think a (low-end) batch drip machine could brew coffee as good as a V60 manual brew.

In reality (low end) batch drip machines are cheap, made of cheap materials, and designed without any thought to the question "how do I extract a good cup of coffee?", usually for convenience (just pour water in). I find that the cheap materials (plastic) used in drip machines can give the coffee a bad taste (this may depend on the type of plastic). It's also easy to forget to clean the drip machine, which can make the coffee gross. Drip machines usually have a large container for water, and if you don't clean it regularly, the water can go bad, which can also result in very bad coffee. Some drip machines also have a heating element, which is a good way to keep the coffee warm, but prolonged heating can also make the coffee taste bad .

In most specialty coffee shops, there are professional batch drip machines, and the cleaning work is done well. In this case, the most common question we encounter is how long a cup of coffee has been in the coffee machine before the waiter brings it. If the coffee is no more than half an hour fresh, it will taste super good. But as time goes by, the taste of the coffee will gradually become very bad.

The V60 offers an option for brewing a delicious cup of specialty coffee in a device that costs about $20 (if you know how to use it properly). Plus, the V60 is easy to clean and travel with, making it a much more convenient option than a low-end drip machine if you want to experiment with new brewing recipes.

In my opinion, there are three challenges when using the V60: (1) consistency from brew to brew/cup to cup (2) maintaining brew temperature while brewing (3) when all brewing variables are intertwined, you have less control over any particular variable.

4. Brewing variables

There are several brewing variables that affect coffee flavor and strength:

• Water-to-powder ratio
• Coffee bean quality
• Coffee Bean Roasting Style and Quality
• Grinding degree
• Grinding uniformity/degree
• Coffee freshness
• Filter paper quality
• Brewing temperature
• Water Flow
• Extraction uniformity and repeatability/consistency
• Water Quality
• Gouache contact time

4.1 Water (coffee) powder ratio

The two (main) ways to describe coffee variations are: (1) strength (concentration) and (2) extraction. Strength is basically how strong your coffee is, e.g. espresso is much stronger than filter coffee. The clarity of the coffee is affected by concentration (as well as many other factors). Strength is usually expressed as "total dissolved solids" (TDS). It is equivalent to the mass of all the non-H2O stuff in the coffee, and can be measured with a refractometer.

Some Brixt optical refractometers are available for around $20; however, accuracy is not very good at ~0.1-0.2% TDS (you also need to convert °Brix to TDS; TDS = 0.85 x °Brix). Refractometers are great for analyzing brews and communicating with baristas, but their data should not replace your taste buds. More accurate refractometers are several hundred dollars.

Ideally, your brew needs to produce a high enough strength (but not so high as to overwhelm your senses) so that you can appreciate the complexity of a cup of coffee's flavor. Strength/concentration involves personal preference, but most people like a concentration of 1.15-1.35% TDS.

Extraction rate is the total mass of coffee grounds dissolved in the coffee liquid.

This variable primarily affects the flavor of your coffee, since different compounds dissolve at different rates in water. You can get a higher extraction rate with less coffee and end up with the same strength. The greater the extraction rate, the more aromatic compounds your coffee will contain, and these compounds have taken longer to extract from the coffee beans. Standard extractions are between 18-22%, with higher extraction rates producing more bitter, astringent flavors. If you're not sure what astringency means, try an unripe pear, or green tea that's been steeped in water at 100°C for 5 to 10 minutes. Lower extraction rates tend to produce more acidic, more vegetal/vegetable flavors. If you already know the strength/concentration (TDS) of your coffee and the water-to-ground ratio (amount of liquid coffee/amount of ground coffee), you can estimate the extraction rate:

Brewing variables in the 2D graph of the Coffee Quality Control Chart (CCC):

(The coffee brewing quality charts published here do not take into account the liquid remaining in the coffee grounds bed (after brewing) and are not suitable for percolation brewing methods like the V60.)

You can already see from this chart that if you’re aiming for standard strength/concentration and extraction (Gold Cup range), you should be using a water-to-powder ratio between 1:15 and 1:17.

For example, if you determine that you prefer a stronger/stronger 1.3% TDS, using a 1:15 water to grind ratio would yield a 19.5% extraction (more acidic), while a 1:17 ratio would yield a 22% extraction (more bitter). What you prefer depends on your taste, but also on your brewing method and equipment. I personally lean toward a 1:16 ratio (20% extraction 1.25% TDS). I think if I had a high-end grinder, I might prefer a 1:17 (with a higher extraction).

A more accurate way to calculate extraction for a percolation brew like the V60 is to assume that the weight of dry coffee grounds in water is twice the weight of dry grounds, therefore, your beverage weight mass will be lighter. A quick way to do this is to move two rows to the left in the coffee brewing chart above. For example, if you set your V60's ratio to 1:17, then follow the 1:15 diagonal line in the chart above to get a better estimate of extraction (this method only applies to percolation brews like the V60).

4.2 Coffee Bean Quality and Roasting Characteristics

Obviously, the quality of the coffee beans is important to brewing a great cup of coffee. But don't let yourself think that's the end of it; if you ignore any of the other variables, then you won't brew a great cup of coffee either.

I personally prefer lighter roasted coffees because they retain the original flavor of the coffee beans. Darker roasts and longer roasted coffees have a longer caramelization time in the aromatic organic compounds, and although the body will be better, you may also notice that the flavors of different coffee beans are not much different when they are dark roasted .

Dark roasted coffee is also more difficult to store without spoiling. When you buy commercial cheap coffee, it is often dark roasted because low-quality coffee beans will not have a noticeable difference in flavor after dark roasting. When you buy coffee in a specialty coffee shop, it is often lightly roasted to highlight the flavor differences between different coffee origins.

If you happen to prefer dark roasts, it doesn’t mean your taste is worse than others, but you don’t need to worry too much about where the beans are from. Dark roasts also seem to produce more static electricity, which means the grounds stick to the sides of the grinder easily when grinding, and they release a lot of carbon dioxide at the beginning of the brew, making it very difficult to brew .

Another aspect to consider is the quality of roasting. Even if the coffee beans (variety) are very good and the roasting degree is suitable for your preference (for example, I like light roasted coffee), if the roasting quality is not good, no matter what you do, you still can't brew a delicious cup of coffee. For example, baked coffee. The advice I can give you here is to pay attention to who is roasting your coffee, try coffee from different roasters, and remember those roasters that you like the most.

The Lido 3 hand grinder (red bar; top), the Porlex hand grinder (red bar; bottom), and the Mahlkonig EK grinder (blue bar) were set up to produce the same average particle size (blue and red circles indicate standard deviation). These graphs were created by spreading the ground coffee particles on a piece of white paper and measuring the projected 2D surface of each particle using ImageJ software. Note that within the same average particle size range, the Lido 3 produces more small particles than the Mahlkonig EK, and the Porlex also produces more small particles than the Lido 3.

4.3 Grinding degree and uniformity

The grind size will have an important impact on the brew, because finer coffee powder has more contact area with the water, so extraction occurs faster and more strongly. When you brew coffee, extraction is mainly carried out by diffusion. ( Diffusion refers to the phenomenon that the molecules of a substance move from an area of ​​high concentration to an area of ​​low concentration until they are evenly distributed, and the rate is proportional to the concentration gradient of the substance. Diffusion is the mass migration phenomenon caused by the thermal motion of molecules, mainly due to density differences.) This means that water needs to diffuse into the pores of the coffee bean cells, grab something, and then diffuse out through the same pores.

Inside a coffee cell

However, if the grind is as fine as for espresso, you enter a new and different extraction process where the individual cells in the coffee bean are broken apart, which allows the water to easily dissolve all the material inside the coffee cells (this method of extraction is called erosion).

Here we will focus on V60, and we will specifically consider diffusion phenomena (although some erosion will also occur during V60 brewing due to the presence of fines).

The larger surface area (caused by the finer grind) will allow water to enter the coffee cells more efficiently, so the extraction rate will be faster. When brewing with the V60, the finer the grind, the higher the coffee concentration and the higher the extraction rate for a fixed contact time between water and coffee powder. However, fine grinding will also slow down the flow of water through the coffee powder bed (the path of water through the coffee powder bed is longer, and extremely fine coffee powder may also clog the filter paper), which also means that your coffee will be stronger and the extraction rate will be higher. In other words, V60 brewing is very sensitive to grind size.

Another important aspect of grind size is that most grinders are unable to produce a very narrow (focused) range of particle sizes. High-quality grinders can produce a narrower distribution of particle sizes, which is a good thing because it helps every coffee particle to be extracted equally .

Below is an example of the particle size distribution of a Lido 3 hand mill compared to a more expensive Mahlkonig EK grinder. I chose a grind setting to produce the same average particle size, but you can see that the Lido 3 hand mill has a greater number of very fines and a wider range of particle diameter distribution - 1.5 to 0.6 mm. I also show a similar distribution for an entry-level Porlex manual mill, where the difference in particle size distribution is quite noticeable.

A more meaningful comparison would be to compare the contact area created by different amounts of particles, rather than analyzing the number of different particles, and to compare the average contact area created by the same weight, rather than comparing the average diameter of the particles.

You can think of the finished brew as coming from several groups of coffee particles of different sizes. Each group has a specific size, and the flavor of the final brew is related to the average of all the groups (some groups will be over-extracted, some will be under-extracted).

In the case of a Porlex grinder, you can't achieve an average extraction of 20-22% without a lot of (over-extracted) fines, but this will also result in an unpleasant astringency. You will therefore be forced to keep your extraction in the 18-19% range, but at the same time, you will not be able to taste the full flavor potential of the coffee beans. I used a Porlex grinder for a while, and although I didn't have a refractometer at the time, I'm pretty sure my extraction was around 18%. I don't understand why hand-poured coffee tastes so good in coffee shops, and it's possible that water quality is a more important reason, which we will discuss later.

In general, various types of burr grinders produce a relatively narrow particle size distribution; the larger the burrs, the more uniform the particle size distribution. Another way to improve particle size distribution is to use a sifter, such as a Kruve. However, sifting out the fines takes at least 2-3 minutes and wastes coffee. Even so, you may not get a completely uniform particle size distribution because electrostatic forces can cause a lot of fines to stick to the larger grind surface.

I'll eventually experiment with the Kruve screen to see if I can discover something interesting, but it's not as simple as the manufacturers would like you to think - they suggest that just filtering out the fines will give you the coffee you want. If you do that, the water will flow through the V60's coffee bed faster, and the result will be a weak and under-extracted coffee. I watched several YouTube videos of baristas comparing coffee with and without the Kruve screen in blind tastings (with the same brew recipe) and were frustrated and confused by the choice of the non-Kruve coffee every time.

One final note about grinding - avoid using spiral/paddle grinders at all costs. They produce a very wide particle distribution and also generate heat during the grinding process which can degrade the flavor of the coffee.

4.4 Coffee Freshness

One of the difficulties in brewing good coffee is keeping the beans fresh. In my personal experience, I have found that it is best to buy/brew the coffee beans within 1 to 3 weeks after they have been roasted (assuming they have been packaged properly) . If the coffee is fresher than this, it will release a lot of carbon dioxide (accumulated during the roasting process), making it difficult to brew. If it is more than this time, the coffee flavor will be significantly lacking.

The four main factors that affect the freshness of coffee beans are: oxygen, humidity, heat, and UV rays , so you should make sure your coffee beans are not affected by all four.

When you buy a bag of fresh beans, make sure the packaging is not see-through and has a one-way valve; the one-way valve expels the coffee's carbon dioxide (which accumulates during the roasting process) outward and prevents oxygen from entering the bag from the outside. Ideally, the bag should also have a zippered, reclosable opening, and the packaging should be small enough to last you a week or so. Avoid buying pre-ground coffee; ground coffee goes bad several levels faster. If you can, store the coffee bag upside down so that most of the carbon dioxide can remain in the bag and prevent oxidation.

Once the coffee package is opened, the flavor of the coffee begins to decline. This is because the carbon dioxide in the bag is immediately lost (usually with a large volatile aroma), and the beans are not protected from oxidation. Every time you reopen and close the bag, more oxygen will enter, accelerating the aging of the coffee.

One way to solve this problem is to divide the large bag of coffee beans you bought into several smaller bags. Make sure the bags are food grade! I currently use 7.7×10 cm aluminum plastic bags, which can store 22 grams of coffee beans. Some other non-food grade plastic bags have a very unpleasant plastic smell. Use the smallest bags possible to minimize the amount of air in the bag. (Also consider using a cheap vacuum sealer)

I recommend doing this right after you open your latest purchase of fresh coffee.

Don't forget to store these bags in an opaque container away from heat and moisture. If you want to get a little crazy you can fill the bags/jars with pressurized inert gas usually carbon dioxide, nitrogen and argon.

If your goal is to keep some fresh coffee for later use (say, for more than a month), I recommend freezing your beans. You must proceed with caution, however; while freezing slows down the flavor decay process, it can also expose the beans to unpleasant odors and moisture if not handled properly.

Home Vacuum Sealer

As a first step, I strongly recommend that you pack the beans in small packages and measure the amount of beans in advance because you cannot thaw the coffee beans and then refreeze the coffee for any problem.

Place the packet in a sealable container and remove only the amount of coffee you need at a time (return the container to the refrigerator promptly).

Household airtight containers

Take them out of the fridge at least a few hours before use, do not open the ziplock bag, and leave them out of the elements for a few hours. The reasons are: (1) to avoid condensation on the beans, and (2) to avoid grinding cold coffee beans directly, which will result in a lot of very fine powder . This is fine for espresso, but not so good for hand-poured filter coffee.

Cold grinding of coffee beans results in a lot of very fine powder

4.5 Filter paper

The filter paper you use in your V60 will have a big impact on your brew time. Different types of paper have different pore sizes. I don't think the pore size of the filter paper is a big deal, just stick with one filter paper once you find a brewing style/brewing recipe you like.

Another role of filter paper is to affect the taste of coffee. There is a pre-soaking step in the V60 brewing process, where you pre-wet the filter paper with hot water to remove as much of the filter paper taste as possible. To verify the effect of filter paper on brewing quality, I tried soaking four different filter papers in hot water and tasting them after the water cooled. Specifically, I tried Hario V60 natural filter paper, Hario V60 bleached filter paper, Hario natural siphon filter paper, and Aeropress bleached filter paper.

Pre-wet the filter paper with hot water before brewing

I found the first two bleached filters to have a bad taste, with the Hario V60 natural filter reminding me of wet cardboard. However, I tried this experiment again during a V60 brew and barely noticed any difference after pre-wetting the filter. In other words, as long as you pre-wet the filter correctly, the filter shouldn't have a strong effect on the flavor of the coffee; note that this may not apply to other V60 filter brands (you'll have to experiment). I ended up going with the Hario V60 bleached filter, just in case.

The V60 also has cloth filters, which are usually used with a siphon pot. After experimenting with them, I strongly recommend never using cloth filters . Cloth filters can make great coffee on the first or second brew (much better body than using paper filters), but cleaning quickly becomes a nightmare (removing coffee oils and bacteria from the cloth). I think the correct way to use cloth filters is to boil them in an odorless disinfectant after each use, then rinse them in clean water (or boil them several times in clean water), soak them in distilled water in a closed container, and keep them in the refrigerator (no more than a week or so before next use).

4.6 Brewing Temperature

As I mentioned earlier, reaching a high enough and stable temperature is one of the main challenges of brewing with the V60. As far as I know, there is not much reliable data to support the recommended brewing temperature, but most people recommend a brewing temperature of 91-94 degrees Celsius. Coffee expert Matt Perger said that brewing at higher temperatures than this also works well.

I agree with that, but you need to remember that different compounds in coffee extract exist at different extraction rates, and those rates depend on the water temperature . If you brew at different temperatures, the relative extraction rates of different compounds will be very different, and the coffee will taste very different. Ever wonder why cold brew coffee has very, very low acidity? It's because acidic compounds can only be extracted at high temperatures. I did some experiments using a siphon pot at 94°C (which is hard to get with a V60), and I didn't really like the results.

When brewing with the V60, I recommend using the hottest water possible because a lot of heat is lost during the brewing process and it’s easy for the brewing water temperature to drop below 291°C, which results in a coffee with a lower acid content. The ground coffee, the V60 itself, and the surrounding air are all much cooler than the water, and even if you preheat everything, your brew temperature won’t exceed 293°C. For this reason, Scott Rao recommends using a plastic V60 filter because it retains heat better than ceramic or glass V60s , and I couldn’t agree more. During the brewing process, I tested the different V60 filters with a thermometer and found that the plastic V60 did indeed retain heat much better.

Another issue that affects brewing temperature is how much water you inject at a given time. If you take multiple small injections, you can be sure that the extraction temperature will be much lower than 91°C. Maybe you will like the taste, but you should also try a higher brewing temperature before making a decision.

I've heard baristas suggest that boiling the water to 99°C, rather than a full boil, results in a better cup of coffee. However, I haven't seen much convincing evidence or reasoning for this. I remember reading somewhere that most of the oxygen (dissolved in water) is lost when the water boils (but a small amount of oxygen is still dissolved in the water), and that oxygen may be important to brewing coffee in some way, but given the amount of pseudoscience that exists in the coffee brewing game, I don't think I can recommend this approach.

4.7 Water flow (stirring)

Extraction efficiency is largely determined by the water-to-coffee contact surface . The speed at which the water is poured onto the coffee (the pouring rate) will determine the subsequent turbulence (faster pouring leads to more turbulence). Turbulence can create fractal-like contact surfaces. High turbulence helps improve extraction (more water-to-coffee blending). I suspect that using the right amount of turbulence is a way to improve brewing repeatability/consistency.

The characteristics of the kettle's spout will affect the turbulence, as will the height of the pour and any up and down motion of the pour. You should avoid up and down pours, and you should try to pour from the same height each time. I personally like a kettle with a long, small opening, as it creates a lot of turbulence without disturbing the grounds.

4.8 Extraction uniformity and repeatability/consistency

First filling. Next time you fill, pour water into the darker areas.

Uniform extraction is a bit like uniform particle size distribution in your grind; you don’t want some coffee particles to be over-extracted while others are under-extracted. There are a few issues to watch out for:

The "channeling effect" problem is one of the biggest problems in achieving uniform extraction with the V60.

Dry coffee particles repel water, so once a channel is formed in the coffee bed, all subsequent water will flow into this channel, while the rest of the bed may still be dry. One way to avoid this is to stir the bed with a spoon or chopsticks (Scott Rao recommends this method), but this method has one disadvantage: repeatability. Stirring the coffee bed has a huge impact on extraction efficiency (by creating a lot of turbulence that presents a higher speed liquid), and it is very difficult to achieve the same amount/strength of stirring every time you brew the V60.

Therefore, while stirring helps eliminate channeling and improves extraction uniformity, it also causes variation in the strength of each cup of coffee. Scott Rao's purpose of stirring is not to simply stir the grounds bed, but a way to reduce channeling and improve brewing repeatability.

In the V60, the center of the coffee bed tends to form a "dry zone". I've seen some baristas online use their fingers to make a small depression in the center of the coffee bed before pouring water. I haven't done enough experiments to know for sure if it helps, but I think there's good reason to think it probably does, and it's easy to do.

Another common problem with the V60 is those "high-and-dry" coffee particles, which are particles that stick to the filter away from the coffee bed. If you try to remove the "high-and-dry" coffee particles by just pouring water into the filter, most of the water will pour over the edge of the coffee bed (resulting in uneven extraction). Scott Rao suggests that (at different stages of the brew) you can shake the V60 filter in a circular motion by hand to eliminate the "high-and-dry" coffee particles.

“High-and-dry” coffee granules

The coffee grounds bed is flat after brewing

4.9 Water quality

Water changes everything. I've heard many times that "coffee is 99% water, so the water must taste and be good!" This is true. But some waters taste great, but the brewed coffee is terrible. The main problem here is extraction. The water must enter the cells of the coffee beans and then bring out the good flavor compounds, and not all types of water can do this effectively. Specifically, the alkaline buffer and the content of minerals (especially calcium and magnesium) are crucial.

This may sound crazy or too complicated, so here's an experiment for you to try: Buy a bottle of mineral water (such as Evian) and brew a cup of coffee with it. Using the same coffee and recipe, brew another cup of coffee with local tap water. Then, do the same thing with distilled water. Try all three cups of coffee. Coffee brewed with distilled water will be the weakest. Coffee brewed with bottled mineral water should be quite strong, but not acidic (mineral water contains a lot of minerals and alkaline buffers). Depending on where you live, coffee brewed with tap water may be somewhere in between the above two examples. Most of the time, coffee brewed with tap water will be weak and lack body, and you can't adjust for this with other brewing techniques.

I’m always amazed at how different coffee tastes when I travel, and even how my V60 brew times vary drastically when I use bottled water vs. tap water. Coffee experts are starting to take notice of the water issue, too. Before this, some World Barista Champions would fine-tune their brew recipes at home, but then use local water during competitions and have terrible results. Then they’d go home and not understand why, and think that brewing a repeatable cup of good coffee was impossible. Now, the World Barista Championship uses strictly controlled water, with the competition water announced before the competition. Specialty coffee shop water may also be carefully treated with water filtration, reverse osmosis, and/or remineralization, depending on the local tap water composition.

When brewing coffee, consider four aspects of water quality:

Total Alkalinity

The total amount of substances in water that can accept hydrogen ions, preventing the water from becoming acidic (smaller pH). Therefore, a high total alkalinity makes your water more stable. However, if this concentration is too high, bicarbonate ions will start to react chemically with the coffee and the taste will become flat and tasteless. The Specialty Coffee Association (SCA) recommends a total alkalinity of 40 mg/l.

Total hardness

This is the amount of calcium and magnesium ions in your water. These ions bind to coffee flavor compounds within the coffee cells and carry them to your cup of coffee. They each bind to different flavor compounds, so both are beneficial and necessary. This is currently an active area of ​​research. The recommended total hardness for SCA is 17 to 85 mg/L.

pH

The pH is close to 7 (neutral). SCA recommends a pH between 6.5 and 7.5.

Clean and hygienic without odor

Basically you don't want chlorine and too much sodium in your water (the SCA recommends less than 100 mg/L).

4.10 Gouache contact time

The contact time between the water and the grounds will have an impact on the strength and extraction of your brew. However, you don't have direct control over this variable in the V60, so think of it as a function of all the other variables interacting with each other. Your filter type, water composition, coffee bean roast style, bean type, and water infusion method can all have a surprising impact on water-ground contact time. It's a good habit to record your brew times to see if you can replicate your last brew well.

5. Determine the grind size

It's often difficult to describe grind size effectively in words, so you should experiment a bit to find what works best for you. Scott Rao recommends adjusting the grind size to finer and finer (without changing any other variables) until astringency/sense begins to appear in the brew, then adjust the grind size back one notch. Another method is to brew a few cups at different grind sizes and then do a blind test.

Using a Lido 3 hand grinder and a 1:16 water-to-powder ratio, my preferred grind size (mark 9) is shown below

6. Preparation of brewing water

Currently I brew coffee with Dan Eilt, I haven't experimented enough with other different water recipes.

You can also make your own brewing water.

First, prepare some magnesium chloride (MgCl2), calcium chloride (CaCl2), potassium bicarbonate (KHCO3), distilled water and a regular-sized glass bottle or something similar. Make sure you order food-grade (not lab-grade or pharmaceutical-grade) products. You'll also need a pipette (a small spoon will work, too) and an accurate electronic scale.

First pour 194g of distilled water into a glass bottle, add 2g of CaCl2, then 2g of MgCl2, 2g of KHCO3. Bubbles should appear and the solution should turn opaque white, stir with a spoon, then cover (do not tighten) and let it sit for a few hours. Stir it again after a few hours, then tighten the lid and put it in the refrigerator. This is your concentrate.

Now get yourself a large container of distilled water (e.g. 4 liters), for one 4 liter of distilled water you will need 40 g of concentrate. Shake the water well and put it in the fridge, this is the water you will use to brew your coffee.

If you think this is too complicated, a simpler and better option is to buy Third Wave Water coffee water and dissolve it in a gallon of distilled water. Third Wave Water filtered coffee water is also not too expensive.

Another simpler method is to mix some bottled mineral water with distilled water, but you need to first determine a brand of bottled mineral water that has the right ratio of total hardness to total alkalinity. I don't recommend it now.

Whichever method you choose, be sure to keep your brewing water in the refrigerator for no longer than 2 to 3 weeks, and always smell the water before using it; if it smells like an old rag, that means the water is contaminated with bacteria.

7.V60 brewing steps

1. Buy a bag of coffee that was roasted about 1 to 3 weeks ago.

2. Boil high-quality water with appropriate alkalinity and mineral content to 100°C.

3. Put 22 grams of coffee into the grinder.

4. Place the V60 filter cup on the lower pot.

5. Fold the V60 filter paper and put it into the V60 filter cup.

6. When the water boils, wet the filter paper thoroughly and discard the water.

7. Put the kettle back on the base and reheat it.

8..Grind the coffee and put it in a V60 filter cup.

9. Tap the V60 filter cup to make the powder bed in the cup flat.

10. Make a small hole with your fingers in the center of the powder bed.

11. Start the timer.

12. Steaming stage: Start in the small pit and pour 66 grams of water at a uniform and fast speed to evenly moisten all the coffee powder (you can gently stir with a spoon or gently shake the V60 filter cup). If your coffee is fresh, it will release a lot of carbon dioxide. If you don’t see bubbles appear, your coffee may be no longer fresh. Steaming time is 30 seconds.

13. Gently fill the water, and beat it to each part of the powder bed as evenly as possible, and stop at about 200 grams. If you still see bubbles appear at this time, it means that your steaming is not done well enough.

14. When the water level in the filter cup drops close to the height of the coffee powder bed, fill the water for the second time until it reaches 352 grams (the ratio is 1:16). Do not allow the coffee powder bed to remain in the air to avoid the temperature of the coffee powder bed dropping too much.

15. When the water level in the filter cup drops low enough, you can rotate the filter cup again.

16. Wait for the water to flow completely through the powder bed and pay attention to your entire extraction time. This time depends on many factors, but it usually ranges between ~2:30 and ~3:30. High-quality grinders (machines) can usually shorten the extraction time.

Enjoy this hand-made coffee.

Article from:roast magazine