Coffee extraction is a professional process that uses water as a solvent to dissolve flavor compounds in coffee grounds. In simple terms, extraction is the process to steep out the flavor essence from coffee beans precisely. For coffee professionals and enthusiasts, mastering the core logic of extraction is the key to unlocking a perfect cup of coffee.

The Goal of Extraction: Gold Cup Standard

As a theory guiding coffee brewing proposed by the specialty coffee area, the Gold Cup Standard indicates that the ideal coffee extraction yield is extracting 18%-22% of the percentage of the coffee grounds that have been dissolved into the water.

Within this range, the coffee achieves a balanced flavor, with good sweetness, acidity, and body.

Under-extraction (<18%): The coffee will exhibit prominent sharp acidity, a thin mouthfeel, and a lack of flavor layers.

Over-extraction (>22%): A large amount of bitter impurities are extracted, making the coffee dry and unpleasant to drink.

Four Core Elements: Precise Control for Flavor Extraction

The final performance of coffee extraction is determined by four elements: grind size, water temperature, extraction time, and water flow/pressure. Each of these is a key variable that affects the flavor.

Grind Size: The "Biggest Variable" in Extraction

The surface area of coffee grounds directly determines extraction speed. If the powder is too fine will cause over-extraction, while too coarse leads to under-extraction.

Recommended Options:

Espresso: Extra-fine grind likes flour, suitable for high-pressure extraction.

Pour-over Coffee: Medium-fine grind size like granulated sugar, balances extraction efficiency and flavor layers.

Cold Brew Coffee: Coarse similar to sea salt, prevents over-extraction caused by long-term steeping.

Water Temperature: The "Flavor Controller" of Extraction

Water temperature acts as an "invisible switch" that regulates the direction of coffee flavor.

Low temperature (85-88℃): Inhibits flavor volatilization and highlights the coffee’s fruit acidity and floral notes, suitable for light roasted beans.

Medium temperature (89-92℃): Balances sweetness and acidity, showcases the coffee’s balanced layers, suitable for medium roasted beans.

High temperature (93-96℃): Stimulates a rich body and bittersweet flavors, suitable for dark roasted beans.

Extraction Time: The "Progress Bar" in Extraction

Espresso: Recommended extraction time is 25-30 seconds.

Pour-over Coffee: Recommended extraction time is 2-3 minutes.

French Press Coffee: Recommended extraction time is 4 minutes.

Cold Brew Coffee: Recommended extraction time is 12-24 hours.

Water Flow/Pressure: The "Power System" of Extraction

The form of water flow or pressure directly affects the extraction uniformity of coffee grounds:

Pour-over Coffee: Gentle circular pouring achieves uniform extraction.

Espresso: High-pressure forced penetration quickly extracts rich flavors.

Immersion Brewing (French Press): Static uniform extraction delivers a rich flavor.

Extraction Order of Flavor

The dissolution of coffee flavor compounds follows a fixed order, which serves as the "scientific benchmark" for extraction degree.

Fruit acids and floral notes in coffee beans typically dissolve first. Then the ideal extraction target is to extract the sweetness and caramel notes. Bitterness and impurities in the beans dissolve last.

The longer the extraction time, the more late-stage bitter compounds will dissolve.

Home Brewing Tips

When making coffee at home, mastering these tips can significantly enhance flavor performance.

1. Grind Adjustment: If the coffee is too acidic, use a finer grind; if it’s too bitter, switch to a coarser grind.

2. Water Temperature: Use about 89-96℃ water for light roasted beans to highlight fruity and floral notes. Use about 85-88℃ hot water for dark roasted beans to balance charred bitterness.

3. Stirring Control: Pour water in a thin central stream to boost sweetness. Or stir vigorously in circles to increase body.

4. Coffee-to-Water Ratio: Recommended ratios are 1:15-1:17 for pour-over coffee. For espresso, it is 1:2-1:3 recommended.

Common Extraction Mistakes for Beginners

1. The longer the extraction time, the stronger the coffee?

In fact, prolonged extraction leads to over-extraction, making the coffee bitter.

2. Using the same parameters for all beans?

Grind size and water temperature need to be adjusted based on roast level and origin flavor.

3. Focusing only on time and ignoring flow rate?

Abnormal flow rate requires adjusting the grind size.

Coffee extraction is a discipline. From the Gold Cup Standard to the detailed adjustment of the four core elements, every step shapes the final flavor expression.

Why not start with adjusting grind size and controlling water temperature, and practice these extraction techniques firsthand? You’ll find that a well-layered cup of coffee with balanced sweetness and acidity is not as far away as you think.

Keywords: coffee extraction

Originally published 08 Nov 2025, updated 08 Nov 2025.