Introduction:As a highly versatile coffee brewing device, the AeroPress has long been beloved by coffee enthusiasts for its diverse extraction methods. This article will provide an in-depth analysis of the high-concentration, low-extraction universal brewing recipe created by 2016 World Brewers Cup Champion Tetsu Kasuya. Using Ethiopian Yirgacheffe (Hamasu) medium-light roasted beans as an example, it details the specific workflow for a 20g coffee dose with a 1:8 coffee-to-water ratio. It also provides key parameters such as grind size, water temperature, and backpressure techniques, along with bypass dilution suggestions and actual flavor profiles — allowing you to recreate competition-level coffee at home.

Thanks to its unique extraction mechanism and high degree of flexibility, the AeroPress has become a playground for many coffee enthusiasts. The official annual competitions dedicated to this device further demonstrate its endless possibilities. What we’re introducing today is a universal brewing method developed by Tetsu Kasuya, the 2016 World Brewers Cup Champion and inventor of the 4:6 brewing method. Through the innovative approach of high-concentration short extraction followed by dilution, it caters to both hot and iced coffee needs.

The essence of this method lies in using20 grams of coffee grounds with 160 milliliters of hot waterat a 1:8 coffee-to-water ratio, with an extremely fine grind size close to flour (finer than the granulated sugar typically used for pour over), extracted directly with boiling water. In practice, first invert the AeroPress plunger and chamber, then add the coffee grounds and hot water in sequence. Use a stirring stick to perform 10 quick stirs, let it sit for 30 seconds, then stir another 10 times. This segmented stirring can effectively improve extraction uniformity.

When the timer reaches one minute exactly, attach the lid with two pre-moistened filter papers already placed inside, then quickly flip the entire device upside down and place it firmly on top of your cup. Next, press the filter cylinder down steadily until all the coffee liquid is fully extracted. It’s important to note that this method results ina highly concentrated extraction (with a final concentration of about 2.98%), so drinking it directly would be overly intense. It is recommended to adjust via bypass dilution by adding 120 milliliters of hot water (approximately six times the coffee dose) or other liquids.

Regarding grind size selection, although the original recipe uses an extremely fine grind close to flour, in practice you should fine-tune based on the freshness and origin characteristics of the coffee beans. Beginners are advised to start with a grind slightly finer than pour over granulated sugar and observe the filtration speed and flavor profile. If obvious channeling or excessive bitterness occurs, you may adjust coarser to a midpoint between granulated and coarse sugar.

For water temperature control, although it indicates using “just-boiled” boiling water, if using light roasted beans or aiming for brighter acidity, the water temperature can be reduced to 92–94°C to minimize over-extraction risks. For medium to dark roasted beans, it is recommended to maintain a hot water temperature above 96°C to fully extract the body and richness. Extraction time is strictly controlled at one minute — too long can lead to bitter over-extraction, while too short may result in under-extraction.

The details of the backpressure stage are crucial: before flipping, make sure the filter paper is fully moistened and laid flat. When pressing down, apply even, vertical force and avoid lateral pressure that could compromise the seal. If you encounter excessive resistance during pressing, it may be due to the grind being too fine or compression being too high — in which case you should stop immediately and check the parameter settings.

For bypass dilution methods, in addition to the usual hot water adjustment, ice cubes or cold water can also be used for dilution in the summer. When making iced coffee, it’s recommended to keep the final drink temperature between 4–8°C for optimal flavor. Based on testing, coffee diluted with 120 milliliters of hot water shows a significant improvement in sweet-acid balance, clearly showcasing the Ethiopian bean's characteristic flavors such as strawberry and guava, accompanied by elegant floral notes.

The key to the success of this extraction method lies in the dual control of a “high-concentration base + precise dilution.” It is recommended that beginners prepare a precise measuring cup and record the actual amount of dilution liquid added and the resulting flavor feedback, gradually building a personal preference database. For advanced users, you may try adjusting the coffee dose between 18–22 grams, or altering the number of stirs and timing rhythm to explore how different variables affect the flavor.

In terms of flavor profile, when executed correctly, this method should present a bright lemony acidity in the foreground, followed by the sweet fruitiness of red berries in the mid-palate, and a lingering caramel sweetness with gentle spice notes in the aftertaste. If the acidity comes across as overly sharp or there is a papery taste, check the quality of the filter paper and whether it has been rinsed sufficiently; if the flavor is dull, it may be due to the grind not being fine enough or insufficient extraction pressure.

In summary, Tetsu Kasuya’s universal extraction method fully leverages the design advantages of the AeroPress. Through scientifically designed parameters and flexible post-brew adjustments, it allows users to reliably reproduce high-quality coffee. Whether you’re aiming for competition-level concentrated flavors or seeking the convenience of daily drinking, this method offers a reliable solution — making it highly worthwhile for AeroPress users to deeply practice and refine.

The above content is compiled by CoffeeHunters, a coffee news website.