Have you ever ground a bag of coffee for french press and wondered why it is often much coarser than other brew methods? Admittedly, this is something that we subscribed to when we were first starting out. Though, in recent years as our knowledge of immersion methods has grown it has begged for a closer look into why this common practice persists.
The most compelling reason is that a coarser grind will reduce the amount of fines produced which makes a cleaner cup that drinks like a filter coffee. The coarser grind will also reduce extraction and strength which the prompts the brewer to counter by adding more ground coffee than usual.
This is how we arrive at low brew ratios for immersion methods that use coarsely ground coffee. Allowing any style of french press to sit for a few minutes will allow the suspended sediment to fall to the bottom, and pouring slowly to keep it low in the press will create a filter-like experience. So we decided to compare our starting point to what we're doing now.
The question is, how do we get the most out of the coffee?
Our traditional approach or our current approach. For this quick test each french press was brewed for four minutes and plunged over 15 seconds. We then decanted them immediately, for destratification before refracting.
Traditional French Press
First we brewed traditionally with a coarse grind setting, using 41.5g of coffee and 500ml of water for a brew ratio of 12:1
The lower brew ratio gives us that full body (1.36% t.d.s) that many seek from this method but at the expense of extraction (16.7%) as we suspected.
Current French Press
In the same six cup french press we then took our current approach of using a grind size slightly finer than drip, one suitable for cupping or pour overs, and using 31.5g of coffee and 500ml of water for a brew ratio of 16:1
The higher brew ratio gives us a lighter body of 1.25% but gets more out of the coffee with an extraction yield of 20.2%.
This indicates what we've been tasting between the two approaches. The way we approach brewing for immersion now has a more balanced extraction, or representation of the coffees flavours, but results in a lighter body than the traditional approach. Unfiltered immersion methods can at times get away with a lighter body as the suspended sediment can trick you into feeling like the body is higher than it is. This is how we've shifted the tasting experience back towards what we're accustomed to from a standard drip strength coffee.
It's true that using a drip or cupping grind will get you a more balanced representation of any coffees flavours, and it's what we've been practicing for a while now.. If you prefer a heavier body in your french press, you can simply add more coffee when using a medium-fine grind. This will achieve better extraction than the traditional approach while getting the strength that can set this method apart.
Have any questions on immersion brewing or new techniques you've been using? Let us know!
Yours in coffee,
Pilot Coffee Roasters.