The Difference In The Usage Of Paper Filter For Pour-over
Till this moment, I have been learning and practicing pour-over brewing for about 5 years, and during that process, I always follow the fixed process of grinding coffee, choose a dripper, put a paper filter in the dripper, wet the paper filter, and the dripper with hot water, get rid of that water, then put the coffee powder into the dripper … The purpose of this is to ensure the extraction of coffee does not contain the flavour of paper, as well as heating the paper and the dripper a few seconds in advance, keeping the component of the paper “unchanged” at the same time as the coffee when you start to pour hot water. But in Japan, people don’t do that, and why? That was the question I had been wondering about during the whole trip until the day I got back, rummaging through my books and doing some experiments to verify it. Hope this article will help us partially answer this question.
A little difference
The story started as we ordered pour-over drinks with Elsanvador coffee at Blue bottle, Kobe. Baristas use V60 designed specifically for Blue bottle and their own paper filter. And they just poured hot water right in after they had added about 20 grams of coffee. Incubate for 45-50 seconds and then continue to pour a fairly large stream of water (about 4-5mm in diameter) with about 100ml of water each time. This should take about 3-3.5 minutes to complete the pouring process. Till here, you might already begin to see the difference? I would like to list some points as follows:
– Filter paper is put straight into the dripper (filter) and not wet before pouring. (omitting pre-wetting paper filter)
– The incubation time (also known as blooming) is a bit longer, normally I would leave it for about 40 seconds (and press the clock before pouring)
– The water is poured evenly and stronger. The diameter of the water flow is 4-5mm compared to normal pouring kettles and the usual way of pouring is about 2-3mm.
After observing and visualizing the whole process, I asked my friend to know that, in Japan, people often prepare like that, they rarely wet the paper filter before preparing it. Strange and hard to understand why?
So what do you use the paper filter for?
If you have been preparing coffee manually, namely pour over with V60, or Kalita wave, Bonmac, etc. then you are no longer unfamiliar with the effects of the paper filter. In essence, when extracting coffee with hot water, the coffee powder blooms and we can get a lot of “things” with water (also called solvents) such as:
– Caffeine compounds (creating a bitter taste)
– Acids, particularly acid citric (which gives a sour and/or sweet taste, like orange, apple or grape, etc.)
– Lipids and fats (viscosity or oil)
– Sugar (sweetness, and viscosity as well)
– Carbohydrates (viscosity, bitter taste).
– And some other insoluble solids, etc
Lots of things, compounds, as you can see above after the coffee has been extracted with water (hot or cold). Besides, the water you use to brew itself has a certain “hardness” (also known as TDS – the total amount of dissolved solids in water), so the finished coffee product after being brewed will be not just a coffee drink with amber colour, but includes many flavors, as well as dissolved compounds in it.
The problem is that not everyone wants to drink a cup of coffee containing that many compounds (including impurities). When brewing coffee with the V60 and paper filter, people often want a “clean cup” where there are only the main flavours of coffee without the oils, fats, or solid compounds mentioned above. Therefore, we use paper to filter these compounds in the preparation, and after years of research and testing, it has been proven that fat, viscous, some hard impurities will be trapped by the paper filter, making sure you have a “clean” and “smooth mouthfeel” cup of coffee.
So do you need to wet the paper filter?
This is the question that makes me wonder the most. Why? Because paper filter for coffee is made from paper, sometimes recycled paper, or from some other source that we do not know. There are yellow paper, white type, some, when picked up, nearly doesn’t have any special smell (usually Japanese white paper filter will not have the paper smell) but some have a heavy smell of wood, smell of old paper (for example, canned paper filter from Melita, available at stores like L’splace in Hanoi). It should be added that the coffee filter paper is similar to other types of paper, that is also through industrial treatment and its composition is also variety, for example:
– 40% – 50% cellulose (note that the structure of the coffee bean is also cellulose)
– 10% – 55% hemicellulose
– 20% – 30% lignin
– 6% – 12% of other organic compounds
– 0.3% – 0.8% of inorganic compounds
For the reasons mentioned above, and by the lab experiments, it is believed that when the paper filter meets hot water, it also changes and produces impurities similar to the extraction process. To test this, you can simply take the filter paper and place it in the dripper, pour hot (or cold) water to see the results. Most of the water obtained after pouring hot water through a paper filter will be light yellow in color and woody smell, and of course, it will affect the quality of coffee if the entire amount of water and compounds blends into the coffee during the brewing process.
Therefore, wetting the paper filter before preparation, also known as the pre-wetting process, will partly remove the impurities of the paper created in the process and ensure the coffee cup is “clean” and “have the flavour as full as possible”.
How about the Japanese concoction?
In other coffee shops in Japan, I haven’t had a chance to ask them why, but with Blue bottle, some points can be referenced and explained as follows:
– With the barista here, they are confident in the quality of their paper filter.
– Without pre-wetting the paper, the paper expands along with the coffee during blooming, giving the coffee and the heat a little more “space” to bloom, the more efficient extraction will be.
– The Blue bottle is confident in its own V60 tool.
In a book about the hand-drip coffee that I had the opportunity to buy in Osaka on the last trip, the author who owns the TORCH donut filter also does not wet the paper filter before preparing it, but he recommends that if you feel that the quality of the paper filter is not good, you can pre-wetting it and wait 15-30 seconds before adding the coffee to brew.
Epilogue
After reading the article, you might wonder: “Why does it have to be so fussy? Why paying so much attention to the detail? ”. Indeed, if you don’t drink coffee frequently or if you just regularly drink dark roasted coffee, you will hardly notice the difference of a “strange taste” from a paper filter. Or, if you consume large amounts of coffee (eg 30-40gr) with a low extraction ratio of 1:12 or 1:13, you will only find the overwhelming characteristic taste of the coffee. There’s nothing wrong with this, and if you don’t care, that’s okay. But if at some point you see, coffee extract is a bartender’s pursuit and discovery towards the roas ter, searching for the flavor and aroma that the roaster leaves in the taste notes. Or if you know that even the roasters are always trying to create the right taste that the growers have formed, you will feel this is an exciting journey with a variety of colors, flavors, and fragrances.
Until one day, you will be like me, always enjoy and cry out in your heart when one morning you wake up, brewing your cup of coffee according to the smell and taste noted on the coffee package that you have bought from a remote place. For a coffee lover, it’s a little bliss, and if you really like this drink, give it love like that.
Source: https://seedtomysoul.com/2018/12/09/su-khac-biet-trong-viec-dung-giay-loc-pha-che-pour-over-o-nhat/