Is Your Coffee Bitter and Astringent? How Does Coffee Grind Size Affect Flavor?

Is Your Coffee Too Bitter or Too Astringent?

Many people who are new to coffee believe that bitterness equals richness, and richness equals aroma. When encountering such customers, we patiently explain the various flavor profiles, how richness doesn't necessarily mean good aroma, and how bitterness isn't always the case. However, for someone who has never studied coffee, this flavor wheel is actually quite fitting! When you taste coffee in your mouth, you can experience its flavors.

In this regard, many enthusiasts, especially those just beginning to explore coffee tasting, can start learning pour-over techniques with coffees that have distinct flavor characteristics like Brazil, Mandheling, and Yirgacheffe.

Brazil represents the flavor profile of American growing regions;

Mandheling represents the flavor profile of Asian growing regions;

Yirgacheffe represents the flavor profile of African growing regions.

Everyone hopes to drink delicious coffee that is both sweet and smooth, with explosive aroma and a long-lasting aftertaste, and they hope to enjoy such coffee every time.

There are many variables that affect coffee taste: time, temperature, brewing equipment, etc., but the most crucial factors for brewing good coffee, besides good beans and good equipment, are the grind settings.

Now that you've selected your beans and equipment, today let's discuss grind size - how fine should coffee beans be ground?

Using the Fuji Royal grinder as an example, the optimal grind size for pour-over coffee is between settings 3-4, which can be compared to fine granulated sugar:

Many brewing guides discussing grind size often mention "salt-like coarseness" or "fine sand-like coarseness."

When you see these descriptive terms, you might not know the exact range. In reality, the most accurate approach is to grind a small amount yourself and compare. Mandheling is typically "fine sand-like coarseness," cold drip is like "sugar-like coarseness," and medium-light roasted Yirgacheffe is slightly coarser than sugar.

Correct Grind Size Creates More Delicious Coffee

The secret to good coffee lies in extraction, but what exactly does extraction mean? Extraction is the process where flavor and aroma compounds from coffee beans are released into water and combine with it, resulting in a delicious cup of coffee.

However, these flavor and aromatic compounds represent different flavors - some bring sweetness, some bitterness, some fruit flavors, and some astringency. These compounds are also extracted at different times.

Medium-fine grind ≈ white granulated sugar (the most common white sugar found in supermarkets, slightly coarser than the finer variety). Generally, pour-over coffee will ultimately settle on a medium-fine grind size because it's very commonly used. As a coffee lover, you should experiment more with your grinder to find your ideal medium-fine grind setting.

Todd, the 2014 and 2016 US Brewers Cup champion, told the author that the order of compounds extracted from coffee is:

Acidity, sweetness, bitterness, and finally astringency.

This means that by controlling the extraction rate, you can control how many compounds dissolve into your coffee. In other words, you can decide the flavor of your coffee. Whether you're making pour-over or espresso, this is the fundamental principle for creating a brewing recipe, and grind size is certainly one of the considerations, as it affects the brewing process.

Image source: Come True

Different origins, varieties, and processing methods all affect coffee taste. Using FrontStreet Coffee beans as reference:

Personal Experience:

Consider altitude: Beans from relatively lower altitudes have a looser texture and are less resistant to extraction. These beans typically use medium grind, such as Brazil and Mandheling. High-altitude beans have a harder texture and are more resistant to extraction, usually requiring medium-fine grind, such as Panama, Costa Rica, Yirgacheffe, and Kenya.

Consider roast level: For dark roasts like Brazil and Mandheling, use medium grind.

For light roasts or medium-light roasts, use medium-fine grind.

Consider date: Typically, use medium-fine grind during the degassing period of 7-14 days. Use coarse grind after more than 1 month, though specific parameters should still be considered based on the individual beans.

When we use a V60 dripper, the coffee bed has greater thickness, and the contact time between coffee and water is longer. Fine powder tends to accumulate at the bottom, and prolonged soaking can easily extract bitterness and astringency. Therefore, it's important to control the amount of fine powder. If your grinder produces too many fine particles at the same setting, you can use a flour sifter to keep the fine powder within a certain range.

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473