Brewing Basics: Drip/Pour-over
Boil water, crush coffee, pour water, drink... that was pretty basic, but lets pull that apart a little bit.
In this we will talk about brewing basics in regards to drip/pour over coffee such as V60, Kalita Wave, Chemex, etc.
When talking about brewing "basics" I think it is important to understand some of the terminology that might get mentioned.
Recipe; all the steps and details that go into brewing your coffee
Ratio; the amount of coffee to water you are using in your brewing recipe
Extraction; the process of pulling the properties from the ground coffee into your cup.
Slurry; the combination of water and coffee in the filter while brewing
Bloom; allowing the ground coffee to degas through the process of applying water
Dial in; the act of finding the best flavor profile within the coffee
Let's start with the very basics mentioned at the beginning
We're not talking about cold coffee here (even though some cold coffee requires boiling your water... I digress), so the first step to brewing your drip/pour over coffee is to boil your water. Everyone uses different temperatures of water to brew their coffee, depending how picky they are and honestly what works best for them. The most common recommendation that I've seen is to let your water come off boil for about 30 seconds, this is said to get it to the perfect brewing temperature. I've even read that if you brew your coffee with your water straight off boil, you could scald the grounds. I believe this to be simply not true when you take into the consideration the high heat the coffee endures going through the roasting process. Coffee is roasted between 370 and 540 degrees F, at that point your water is far into the gaseous state. I find the best way to allow my water to cool down just enough is to rinse my filter and preheat my gear. By the time you get done with that, you should be right in the ballpark that you want to be in with water temperature.
Crushing coffee, in other words...grinding! You'll need to get your coffee from whole bean to ground coffee somehow. You can do this however you like; blade grinder, conical burr grinder, hand grinder, ceramic burrs, metal burrs, smashing your beans with a hammer (desperate times call for desperate measures). One of the easiest ways of getting a uniform delicious cup of coffee is to have a consistent grind when brewing. This means that your ground up coffee isn't made up of boulders (large pieces) and fines (dust like powder) and everything in between, but a nice consistent grind size where everything is the average. To get these kinds of results, a burr grinder of sorts will do a much better job than a blade grinder... or a hammer. Your extraction and brewing time are dependent on your grind size. A finer grind will restrict the flow of water and will slow your brew time down. A finer grind will also have a faster extraction rate due to the increased surface area on the coffee that the water can come in contact with. A larger grind will do just the opposite, allow water to flow through faster, speed up brew time, have a slower extraction rate. Your grind size will vary depending on how much coffee you plan to brew and what brewing method you are planning on using. A brewing device such as a Chemex will require a longer brewing time as its filters are thicker and you are typically brewing higher volumes of coffee. Therefore your grind size must be larger so you don't over extract the coffee with your long brew time . Brewing devices such a V60 or Kalita Wave will take less time as you are typically only brewing enough coffee for one cup at a time, therefore you will want a finer grind to extract the coffee quicker within the short brewing time.
Now that you've boiled your water and ground up your coffee, you need to actually pour water through it. Most brewing recipes (no matter the device using to brew) recommend allowing your coffee to "bloom" for 30-45 seconds. The fresher your coffee, the longer it should bloom (45s). The not-as-fresh of coffee doesn't require as much time to bloom (30s). Blooming allows for your coffee to off gas itself before the full brewing process begins. These gases generally have an unpleasant taste and you don't want the water pulling them into your final cup of coffee. Your coffee will naturally be degassing itself after it is roasted and bagged. To bloom your coffee you add roughly twice the weight of water to coffee that is in the filter. Ex. brewing 15g coffee, bloom with 30ml of water*. Coffee that has been more recently roasted will have a larger bloom than a coffee that has been off roast for a few weeks or longer. When I say "larger bloom" I mean that it will rise and bubble more in the bloom stage.
Once your bloom stage is done, you can work on pouring the remainder of your water into the brewer until you've reached your desired water weight/volume. When working with pour over coffee, it is easiest to use a "goose-neck" kettle when pouring. A goose-neck kettle has a long thin spout that allows you to easily control the flow of water so you can pour exactly where you want to in the coffee slurry and however fast you need to in order to maintain a proper brewing time. When pouring, I find it is most effective to pour in a circular fashion (like a spiral) working your way from the inside of the slurry to the outside of the slurry. This type of pouring allows water to evenly flow through all of the grounds and keeps your water distribution even throughout the whole process. Some people choose to breakup their pours into a few stages through the brewing process (called pulse pouring) and others choose to just do one long steady pour through the entire process. I personally use the long steady pour method. The most important thing to remember is that if it's working for you and you enjoy the taste of your coffee, there is no need to change it.
*fun fact: 1g and 1ml of water are equal! This will allow you to measure the volume of your brewed coffee with a kitchen scale.
Now that you've meticulously poured your water through your coffee, you can now enjoy the spoils of your labour. That's right, pull your favourite mug out of that cupboard, serve up your coffee, sit down, relax and sip away. If you want one more step, you can preheat your cup before you serve up.... just pour some of the hot water from the kettle into your cup, swish it around, discard it and then pour your coffee in there. Preheating your cup of choice allows your coffee to maintain it's heat for a bit longer after brewing and won't have the shock of going into a cold cup. But you do you.
When drinking your coffee, take note of how the flavor changes as it cools throughout your drinking time.
Let's get into some of the nerdy bits
Brewing pour over coffee involves a few different variables: ratio, grind size, extraction time. These are the three variable at play when dialling in a new coffee. All of these variable also play off of each other.
Small grind size = slow drain time, faster extraction
-the sweet spot is somewhere in here-
Large grind size = faster drain time, slower extraction
When brewing coffee the most common ratio to use hovers right around 1:16. This ratio is not set in stone by any means and will change depending on the profile of the coffee and your personal taste palate. In almost all cases it doesn't go any lower than 1:15 or any higher than 1:17. It also doesn't just jump around from 1:15 to 1:16 or 1:17, you can fine tune it further than that. Try minimal adjustments like 1:16.3 or 1:16.6; now we're getting crazy. When trying to dial in a new coffee, it is important to keep the ratio consistent from one brew to another. If you find that your coffee is taking too long to drain or it's draining too quickly, it is easiest to adjust your grind size by small amounts at a time. Using a finer grind will both slow the drain time and increase the extraction on your coffee. The reason that a finer grind increases the extraction is because now there is more surface area on the grinds for the water to come in contact with, meaning it is a lot easier for the water to extract the properties from the coffee. If your grind is too fine and your coffee takes too long to drip, it will come out as an "over developed" cup. This means that you have pulled too much out of the coffee and have left the sweet spot. An over developed cup can lead to an unpleasant taste that is harsh, bitter, dusty, dry, etc..
Finding that sweet spot is crucial to producing a quality cup of coffee. Coffee naturally stores sugar properties inside of it, the sugar properties in a coffee will vary from roast to roast. These sugar properties give it the pleasant, vibrant, full body, fruity taste! In this case, finding the sweet spot is quite literal. If you brew your coffee for too long or over extract it, you have brewed out all of the sugar properties and now have started to extract the properties that bring on a bitter and dull taste. The goal is to have your brewing process end before there are too many of the bitter properties extracted. On the flip side, under extracting your coffee doesn't allow it to extract the sugar properties from the coffee. An under developed cup can taste dull, bland, watery, faint, etc..
Coffee that is fresher will allow a more flexible sweet spot that will be easier to find. Don't you dare touch that coffee until it is at least 2-3 days off roast, the coffee is far too gassy at that point and will likely taste horrendous. Coffee that is a bit more on the stale side can be very difficult to find the sweet spot...sometimes you won't be able to find it at all depending how stale the coffee is!
Here is a helpful diagram from the wonderful folks over at Barista Hustle that helps you navigate your way to a delicious cup of coffee.
Hopefully this gives you a bit of insight on how to start brewing or how you can tweak your current brewing process!
Keep your eye out for future posts on specific recipes that I will be posting!
Always strive to brew coffee better.