Exploring Coffee Flavours Through Time: A Brew Comparison Using the Hario Switch, French Press, and AeroPress
At Fission and Bloom, we love exploring how different brewing methods can reveal the intricate flavours hidden within each coffee bean. In our last blog post, we discussed how brewing time affects coffee flavours using the V60 pour-over method. Today, we’re taking it a step further, using the Hario Switch, French Press, and AeroPress to demonstrate how time influences the flavour profile of your coffee. This experiment highlights the balance between sourness, sweetness, and bitterness, and how the timing of your brew can create a perfectly balanced cup.
The Hario Switch: Tasting the Coffee at Different Stages of Extraction
To begin, I used the Hario Switch, a hybrid brewing tool that combines immersion brewing with the control of a manual pour-over. Here’s how I approached the brew:
I started by warming the filter paper, the Hario Switch, and the beaker with hot water to ensure an even brew temperature.
I added 15 grams of freshly ground coffee to the filter paper and tared the scales.
I then poured 50 ml of hot water to allow the coffee to bloom, releasing the initial gases and starting the extraction process. After the bloom, I added another 50 ml of hot water.
At 2 minutes, I lowered the switch to release a small amount of coffee into the beaker. When I tasted it, I found the coffee to be sour—this is because the flavours that dissolve the fastest, like acids, are extracted early in the brew.
I continued adding 50 ml of water at one-minute intervals to a maximum of 200 ml and tasted the coffee every minute. At 3 minutes, the sourness had reduced, and I began to notice a rising sweetness. The balance between sour and sweet was pleasant, and I could have stopped the brew there. However, as I let the coffee draw down for longer, I noticed that bitterness began to creep in, as some of the slower-extracting compounds dissolved into the coffee.
This led me to reflect on the importance of timing—even a slight delay can result in a brew that’s more bitter than desired. I decided to try a different method to avoid this over-extraction while keeping the same balanced flavour.
French Press Experiment: Finding the Perfect Brew Time
Next, I used a French Press with the same variables: 15 grams of coffee, 200 ml of water, and the same grind size. Since I knew from the Hario Switch experiment that the flavours were balanced around the 3-minute mark, I aimed for a similar extraction time. The advantage of the French Press is that I can stop the brew more quickly. A disadvantage is that it does not filter the fines like filter paper does (because of this, people add a circular-cut piece of filter paper to the French Press).
After steeping the coffee for 3 minutes, I pushed down the plunger and transferred the brewed liquid into a V60 with a wet filter paper. This method gave me a cleaner cup, but I encountered an issue: the fines—tiny coffee particles that aren’t filtered by the French Press—agitated during the transfer and clogged the V60’s filter. As a result, the draw down took far longer than expected. While the coffee was still hot, I had to stop the process midway to ensure the brewing time didn’t stretch too long.
This presented a new challenge: how could I achieve the clean cup I wanted without the delays caused by the fines?
AeroPress to the Rescue: Speeding Up the Process
To solve this, I repeated the French Press experiment but this time transferred the brewed coffee into an AeroPress with two filter papers inserted. By using the AeroPress plunger, I was able to speed up the extraction and push the coffee through the filters more quickly. This reduced the problem of clogging caused by fines and resulted in a clean cup with the balanced flavours I was looking for.
What I found most interesting was that even though the French Press brew transferred to the AeroPress was similar to the V60 in terms of overall taste, the process was faster and more controlled, allowing me to avoid the bitterness that might have occurred with a longer draw down time.
What This Experiment Reveals About Coffee Flavours and Timing
This experiment highlights how time plays a crucial role in coffee brewing, especially when using methods like the Hario Switch, French Press, and AeroPress. Early in the extraction, sour and acidic flavours dominate, while sweetness begins to emerge in the middle of the brew. If the coffee is left to brew too long, bitter compounds can start to overpower the flavours, leading to a less enjoyable cup.
The AeroPress provided a faster way to achieve a clean, balanced coffee, but the French Press, combined with the AeroPress, allowed for more control over flavour extraction without the clogging issues I experienced with the V60.
Experimenting with Your Own Brews
This experiment is a great reminder that brewing coffee is all about trial and error—every variable, from the grind size to the water type and temperature and brewing time, affects the final cup. If you want to try this at home, start by experimenting with different brew times and note how the flavours change. You might be surprised by how much difference even one minute can make!
At Fission and Bloom, we believe in unlocking the full potential of every coffee bean. Whether you prefer the clean flavours of a pour-over, the robustness of a French Press, or the quick efficiency of an AeroPress, understanding how time affects the extraction process is key to creating the perfect brew.
If you’re curious about trying this for yourself, give it a go with our Kelloo coffee beans, and explore the range of flavours that reveal themselves with every passing minute. Happy brewing!
