A well-equipped home office has become commonplace amongst remote and hybrid workers. However, there is one aspect of the perfect home office that is often overlooked: Great coffee.

In this post, I will go over some of the basic theories of coffee brewing and extraction. Further down I will also share a few concrete tips on how to improve your coffee game at home that easily matches your luxurious office brew or favourite café. Beware, access to consistently delicious coffee at home might make you want to avoid the office even more!

The 5 tips are:

  1. Buy good quality beans
  2. Grind your beans
  3. Measure your coffee and water
  4. Control the temperature
  5. Experiment

After we cover the coffee basics I will explain each of these tips in detail in the last section. Having some ideas of the process, extraction and variables at play during coffee brewing will help you better understand the tips later in this post. If theory isn’t your thing feel free to skip the chapter on Coffee Basics and jump straight to the 5 Tips below.

Note: the tips I present will be most helpful for manual brew methods (Drip, French press, Moka pot, v60, Aeropress…) and not necessarily for espresso, bean-to-cup (automatic) or others.

Coffee Basics

Process

To get the beautiful aroma of a cup of joe, the myriad of chemicals responsible for its flavour profile need to be extracted from the beans. Harvested coffee beans are dried and subsequently roasted (sometimes at a much later time) to prepare them for brewing. Roasting brings out the aromas through various chemical reactions (Maillard reaction, caramelisation, pyrolysis…). During the later stages of roasting, CO2 builds up and will continue to leave the beans after cooling through a process called degassing.

We distinguish different types of roast depending on the time in the roaster and the resulting colour of the beans. Broadly, roasts are categorised into light, medium and dark. Light roasts tend to carry bright, floral and fruity flavours. Medium roasts usually taste more balanced with increased body and less acidity. Dark roasts are characterised by bold and smoky flavours, and often have visible, shiny oil on the surface.

Extraction

Right before brewing, we want to grind the beans to increase the surface area and achieve a uniform particle size that will accelerate the extraction of the aromas. When coffee grounds now come into contact with hot water in your brewer, chemical compounds will leave the grounds to form a solution with the water: the desired coffee!

Different types of chemicals get extracted at different speeds which generally happens in this order: fats → acids → sugars → fibres.

The longer you brew the coffee, the more compounds you will extract. Be careful, an over-extracted coffee will taste burnt, bitter and dry — a bit like tobacco. On the other hand, an under-extracted coffee will taste acidic and sour. Balance is key here — as only a Sith deals in absolutes.

Variables

Four variables come into play during the brewing process, together they will help you achieve a well-rounded, sweet cup that shows the full flavour profile of the bean.

  1. Ratio The ratio of the amount of water and ground coffee. A ratio around 1:15 (65g ground coffee/litre water) is a good starting point for many brews (Aeropress, french press).

  2. Temperature The temperature of the water that is in contact with the ground beans. Depending on the method, you find temperatures between 80–96°C (not boiling, as this will extract harsh, burnt flavours). Temperature stability during the brew matters for a well-balanced drink.

  3. Time The time the ground coffee is in contact with the water for extraction. This can be between 20 seconds and 5 minutes, depending on your brewer. The longer you brew, the more you extract (but maybe also of the bad, bitter stuff).

  4. Grind Size The size (and distribution) of the ground coffee particles. Different methods need different grind sizes and will generally benefit from a narrow distribution of particle size. Finer grinds lead to a higher extraction.

Keep these variables in mind for you to adjust your coffee to your liking. They are also essential parameters to change when dialling in new beans to bring out the full aroma profile. For most home brewers, ratio and time will be the easiest to adjust.

5 Tips That Will Improve Your Coffee

  1. Buy good quality beans Garbage in garbage out also holds for coffee. You will get the biggest improvements in taste by buying good quality whole beans. That doesn’t mean you have to hunt for 30 EUR bags of highly prized micro lot single origin beans. Even higher-grade supermarket beans in smaller (250g) bags will likely be a step up from large vacuum-sealed Lavazza and Illy bags.

Beans from grocery shops tend to be roasted very dark, shifting all flavours to a burnt, tobacco-like taste. Make sure you pick Arabica beans and try finding light or medium roasts. Light and medium roasts will offer a much wider flavour profile — although can be a bit more difficult to extract.

If you can, look for bags of beans with a roast date printed on them and purchase them within a month of roasting. This ensures the beans are still fresh and retain their taste. To keep them fresh and tasty at home, store beans away from oxygen and sunlight and try to finish a bag within 2–3 weeks. Keep them in the bag you’ve bought them in if you don’t have an airtight container (a mason jar in a cupboard will do well here).

A great place to find new beans and explore different coffees will be your local coffee shop or roastery. Baristas and roasters will be helpful in finding great beans you will enjoy. Additionally, most small-scale roasters care deeply about their beans’ origins and the sustainability of their coffee production.

If you want to buy coffee that is environmentally sustainable and supports farmers, small roasters with transparent supply chains are preferable.

  1. Grind your beans Notice how I spoke about buying whole beans and not ground coffee in the last section? Well, the second biggest improvement to your home-brewed coffee will be to grind the beans freshly.

Ground beans have an increased surface area and will allow for good extraction. They do go stale quickly (through oxidation), that’s why it’s better to buy whole beans. To avoid brewing with stale coffee, it is also best to grind the beans immediately before use (Ideally within 15 minutes).

You will need a decent grinder to grind the beans at home. I won’t go into details but some good options available for budgets upwards from 50€ are 1Zpresso (manual) and Wilfa Svart (electric). Avoid blade grinders and expect to get what you pay for.

Grinding at home not only gives you the freshest coffee taste but also allows you to control the variable of grind size. In other words, you can adjust your brew to your liking and maximise flavours across different brew methods that require different grind sizes (Aeropress vs french press, for example). For optimal extraction, it is generally best to grind as fine as you can so the coffee is not too bitter and you still enjoy it.

If buying a grinder is not an option for you at the moment, you can also ask your local coffee shop to grind the beans (if you buy them there). Tell them which brew method you will use and they will hopefully pick a good grind size for you.

  1. Measure your coffee and water Every baker knows: spoon (volume) measures are not accurate. It’s the same for weighing coffee. Ditch the spoon and get a scale. Being accurate with your coffee-to-water ratio will help produce consistent brews day after day. It will also allow you to experiment with new beans and recipes by adjusting the ratio in a controlled manner (some people take notes of their brews: beans, grams of water, grams of coffee, time → how did it taste).

If you are a creature of habit (or just lazy) don’t worry too much about weighing beans and water once you perfected your recipe. If you have found ideal doses for coffee and water and you know what they look like (for example 2 full spoons, 1.5 mugs of water..) you might not have to weigh it again every time. Of course, this only works if you keep all other variables constant (same beans, same grind size…).

When you buy a scale make sure you get one with at least 0.1g accuracy which most dedicated coffee (barista) scales will do. A nice side benefit of owning a coffee scale is that most will come with a handy timer function so you can control brew times, too.

  1. Control the temperature Here again, control of the temperature allows for consistency and experimentation. If you can, get a temperature control kettle (or another brewer where you can adjust temperature). If needed, preheat your equipment and cups for more thermal stability. Preheating your brewer will reduce the drop in temperature when the water hits the equipment.

It might be that you only have a traditional kettle available, one that “just” boils your water (100°C). If that’s the case just wait a bit before pouring the water to cool it slightly. As mentioned, boiling water is usually too hot and will leave you with over-extracted, burnt-tasting coffee. Use a thermometer to quantify the cooldown if you can. If that’s too much work just try to be consistent with the cooling and use determined amounts of time (say 1 minute to cool down in the kettle) to make sure every brew is the same (at the same temperature). Lowering your brew temperature will also help you in avoiding unpleasant, harsher aromas in a darker roast.

  1. Experiment Finally, experiment! There are surprising flavour profiles to explore in coffee. Beans from different origins can have flavours running from blueberry or citrusy to vegetal, chocolate or even tea-like. Even after many years of trying coffee beans from all over the world I still discover new aroma profiles every month (not all are necessary to my liking). Your barista at the local coffee shop will be a helpful guide to exploring beans, origins, roasts and brew methods.

At home, you can use the above-discussed variables to experiment with extraction and squeeze out as much taste from the coffee as you can. Just make sure you only vary one (or two) variables at a time so you can improve or dial-in beans incrementally. There is no right or wrong in taste. Keep an open mind, experiment and be amazed by what the world of coffee has to offer.