Brewing coffee is a balancing act. There are many different ways to roast, brew, and prepare coffee, so it can be difficult to decide which method is right for you. It is helpful to understand how coffee brewing works and how brew methods differ. After that, you will have the knowledge necessary to make a choice about which devices and methods would be most effective for the coffee you enjoy drinking.
The following text will focus on the physical and chemical processes of coffee brewing, starting with the pourover method, which is one of the most simple and popular methods. We will also give a step-by-step guide on how to brew coffee using the pour-over method, as well as what equipment to use.
Why Pourover Brewing is Different
In contrast to immersion brewing methods, like a French press, pourover coffee continuously saturates the coffee grounds with fresh water for most of the brewing cycle. This promotes a faster, more efficient brew. Therefore, it is suggested that the less fresh water is used, the longer it can be used without renewing it. Less fresh water should be used so that it can be used for a longer period of time without renewing it. When brewing pourover coffee, it is key to promote even extraction. We’ll go over how to do this below. Pouring a single stream of water over coffee grounds results in an uneven extraction, with some parts of the bed extracting more than others.
This means that when you use a manual brew method, like pour-over, you have more control over the variables that affect the coffee. This allows experienced brewers to change the flavors in their cup, but it also means that people who are new to brewing might not get the results they want right away.
However, understanding how coffee brewing works can demystify pourovers. There are three main extraction phases when brewing coffee: wetting, dissolution, and diffusion.
Phases of the Extraction Process
WETTING
Wetting the coffee refers to adding water to dry coffee grounds in order to make them easier to work with. This is typically done when making cold brew coffee. You need to think about the entire phase as one unit because it is not as easy as it may seem. Roasting coffee produces carbon dioxide gas as a major byproduct. The carbon dioxide that is trapped in the cell structure of lighter roasted coffee beans leaches out slowly over the course of several weeks. The dark roasting process for coffees forces the CO2 out of the cells within a few days. The attribute of dark roasts that coffee is roasted past the “second crack” phase is why there are some notes below about how roast level can affect brewing.
The hot water causes the CO2 to escape from the coffee grounds, forming bubbles. If carbon dioxide gas is escaping, water is not able to enter. Picture shoppers on Black Friday. If you opened your store for business at the same time as a fire drill, it could be a disaster. This would mean that everyone wanting to enter the building would have to wait until everyone that wanted to leave the building had left.
Add enough water to the coffee grounds to wet them, then stop and let the gas escape for 30 seconds. When you see the coffee grounds swell and expand, this is called a “bloom.” This step helps the coffee grounds fully saturate and extract solubles from the center of each grind particle, rather than just the edges.
DISSOLUTION
The word “dissolution” means the same thing as the word “dissolve.” Once the coffee grinds are fully wetted, the hot water will dissolve the materials that can be dissolved in the beans’ cells.
The difficulty in making great coffee lies in the fact that it contains both pleasant and unpleasant organic substances. The fortunate thing about coffee chemistry is that the desirable flavors dissolve in water more readily than the unpleasant-tasting substances. This means that achieving a good brew is simply a matter of stopping the brewing process at the ideal moment–after the desirable flavors have dissolved, but before the unpleasant flavors start to take over.
DIFFUSION
During diffusion, molecules of the dissolved stuff diffuse out of the coffee grounds through a process known as osmosis. Our coffee grounds’ cell walls are semi-permeable membranes, so the osmosis pressure drives the brew out of the highly concentrated chambers of the coffee grounds and into the more watery surrounding environment.
In an immersion brew, the coffee is fully saturated and sitting inside of the brew water, and the process happens naturally. Diffusion occurs in pourover brewing as new water is added to the filter and rinses the brewed coffee, which is full of dissolved coffee solids, into the vessel below.
The Variables: How You Can Tweak Extraction
About two thirds of the roasted coffee bean is insoluble cellulose, which is similar to the material tree bark or the stem of a dandelion is made of. The other third is dissolvable in water. Most of the soluble third is good stuff, particularly various organic acids and sugars. The remainder of the molecules are longer chains that we associate with astringent and bitter tastes. When we extract 19-22% of the coffee’s mass, we create a happy balance of flavors. If you add more than the recommended amount, the drink will have a strong, bitter taste. If you don’t use enough coffee, the flavors will be weak and unbalanced. If you use light roasted coffee, it will be sour.
The main variables that you control in coffee brewing that will influence extraction are the ratio of coffee to water, grind size, brew time, brew temperature, and agitation. The best automatic drip coffee makers will have a consistent brewing temperature of around 198-202 degrees Fahrenheit, and an evenly dispersed showerhead. As long as you ensure the reservoir has the correct amount of water, weigh out the coffee beans in the correct ratio, and grind them at the right setting, your brew will be consistently delicious.
There are many variables that can affect the speed and evenness of coffee flavor extraction. If you want to be a successful photographer, it is a good idea to invest in some equipment.
Brew Variables That Affect the Taste of Coffee
This can be for a number of reasons, but the most common one is simply that your grind is too fine or too coarse If you’re finding that your coffee recipes are sometimes coming out wrong, it might be because your grind is too fine or too coarse. The reason your coffee may not be coming out the way you want it to is likely because coffee is more complex than it is simple. You may need to look past your recipe to find the problem.
To start making better coffee, first get to know the 4 basics of coffee brewing. You can make a great cup of coffee using any brewing method, as long as you follow a few simple tips.
If you don’t like the taste of your coffee after trying these tips, there are many other things you can try to improve the flavor.
Variables That Affect Flavor:
Now that you know where the sweet spot is, you can learn what variables to tweak to get you there!
GRIND
Grind size affects the speed of a coffee extraction. One way to think of the difference between a coarse grind and a fine grind when it comes to coffee grounds is to imagine pebbles and sand. Water moves more quickly through pebbles than sand.
RATIO
You need the right ratio of coffee grounds to water, depending on your brewing method, the type of coffee beans, and your flavor preference. If your coffee to water ratio is not correct, you will probably end up with coffee that is either too strong or too weak.
TIME
Time can be a result of grind size and ratio in some brew methods, in others it is a controllable variable (ie the Clever Dripper, Aeropress, etc.) Adjusting the time adjusts the extraction.
Adjusting Your Variables:
As you brew your coffee, be sure to pay attention to the ratio, grind size, and brewing time. By having a starting point, you will have something to reference as you taste.
Too salty? To bitter? You can get closer to the “sweet spot” by making small changes, but it’s important to know where you began.
Next, taste your coffee and decide how you want the flavor to change. Adjust a key ingredient to match your desired taste.
IS YOUR CUP SOUR?
This means your coffee could be under extracted! You can extend your extraction time and get your brew closer to the sweet spot by changing the following variables.
GRIND
Making your grind more fine will slow the extraction.
TIME
Extend your brew time for a longer extraction.
RATIO
Increasing the amount of coffee grounds will slow down the overall extraction time, and increase the surface area of coffee that can be extracted.
IS YOUR CUP BITTER?
This means your coffee could be over extracted! There are some variables you can change to make your extraction time faster and your beer closer to the sweet spot.
GRIND
You should make your grind more coarse to speed up the extraction process.
TIME
Shorten your brew time for a shorter extraction.
RATIO
To make a less strong coffee, either use less coffee grounds or more water. This will reduce the amount of coffee that is extracted from the grounds.
Other Variables to Try:
If you want to go further down the rabbit hole, or adjusting the grind, time, and ratio isn’t getting you where you want with your coffee, try adjusting one of the following variables:
TAMP
The level of compactness of your coffee grounds can affect how quickly or slowly the coffee is extracted when using a brew method that requires tamping, such as espresso shots.
FLOW RATE
The speed of the release of water can affect variables such as channeling and extraction time, so work to pour at a consistent rate.
PRESSURE
To make a cup of coffee with a rich flavor and a creamy crema, you’ll need to use 9 bars of pressure to pull an espresso shot. Want a cleaner cup? A daintier filter roast will fit the bill.
CHANNELING
Be sure to evenly distribute your coffee grinds in your bed of coffee, so as to avoid any clumps. Water extracts through coffee grounds in the path of least resistance, so any inconsistencies in the coffee bed can cause over- and under-extraction in different parts of the bed as the water takes a focused channel through the grounds.
TEMPERATURE
The ideal temperature for brewing coffee is between 194° and 214°. Depending on which part of that range your water is when you brew, the flavor can change. If you want your coffee to be sweeter, brew it at the higher end of the temperature range. Want to introduce more acidity? Brew at the cooler edge of the range. The flavor of your coffee might change as it gets cold, so you should drink it at the temperature you like best.
AGITATION
How you stir your coffee grounds can affect the way the coffee extracts. Play around with different techniques.
BEAN TYPE
All of these elements can affect the flavor of coffee – single origin, blend, process style, cupping score, terroir, varietal, fermentation, and age. If you are working with a naturally more acidic bean, you’ll want to adjust variables, like the roast, that introduce more sweetness. If your beans have a richer, nuttier flavor, try brewing them with an espresso shot or in a clean Chemex.
ROAST STYLE
Lightly roasted coffees taste differently than darker roasted coffees. If you’re not satisfied with the flavor of your coffee no matter how much you tweak it, you might want to try a darker roast. If you want coffee with a more fruity flavor, make sure the beans aren’t roasted too dark, as this will make it more difficult to get the desired flavor using your chosen brewing method.
SKILL
This is the most infuriating and empowering variable of them all. The hardest thing to control in regards to your skill level is yourself, however it can be enjoyable to work on and gets better over time. As you brew coffee and experiment with different variables, keep track of your recipes and the changes you make. Your taste buds and skills will improve over time. You could be your own best barista!
MOST IMPORTANT TIP: KEEP IT SIMPLE
Whether you are just starting to explore coffee or you have been enjoying it for years, it is best to focus on one change at a time. Trying to tackle too many variables all at once can be overwhelming and decrease your chances of success. To create your perfect coffee recipe, start by adjusting one variable at a time.
It is helpful to know where you are starting from and to make gradual adjustments when trying to perfect your coffee brewing technique. Making small changes one at a time will help you to determine which adjustments improve the taste of your coffee. It also keeps you from getting overwhelmed. As long as you’re enjoying yourself, it’s perfectly fine to obsess over coffee. However, remember to keep things in perspective and enjoy the process.
In conclusion, keep your messages simple and enjoy yourself!