Now that you’ve learnt some basic concepts about drip coffee, let’s talk about a slightly advanced topic which most people overlook easily: filter paper.
You might think that filter paper is a minor thing to talk about in a starters’ guide. I thought so at the beginning. It’s just a piece of paper that does not worth spending the time studying.
After seeing James Hoffman's experiment, I changed my opinion. If you are using a Hario V60 paper, I strongly suggest you have a look at his video. The quality of filter paper produced in different factories is varying, and with different production techniques and materials, the taste of coffee can be greatly affected.
Here are 8 things to consider when choosing your filter paper:
1. Water permeability
The water permeability affects the flow rate of your coffee, and this is related to the structure, density and texture of the filter paper. The flow rate and extraction time of different filter papers can have up to 30-second difference using the same equipment and parameters.
White-coloured filter papers are bleached. Does it affect our health? Top-quality brands equip themselves with an advanced technology that uses biologically active enzymes for bleaching, which has no impact on the environment or human body. This technology is also widely used in the medical field.
Personally, I prefer bleached filter paper because the paper itself has less taste.
If you advocate "natural flavor", unbleached brown filter paper is a your choice. Note that they are more papery in taste, so it is advised to rinse the filter paper before brewing coffee to avoid unpleasant paper taste in the coffee.
Fragile filter paper can easily be damaged during brewing, affecting the adhesion of the paper with the dripper and the performance. The structural change of the filter paper also affects the brewing time and extraction.
Most of us choose filter paper from the same company as the dripper, thinking that they will fit together well. This is understandable. However, since most drippers on the market are cone-shaped, under the premise of paying attention to the degree of the shape of the dripper, you actually have the freedom to choose other cone-shaped filter papers.
Some drip coffee producers do not promote or sell their own filter papers, but instead encourage users to search for other brands. It actually makes a lot of sense, as filter paper production is another industry that requires a lot of resources to be invested in research and development.
That also explains why different brands of filter papers can have such huge variation in quality, since it is not the main product in many companies.
5. Smell and Taste
This is your overall sensation. During the time of brewing, we need to be able to tell the level of extraction through smelling. So, when choosing filter paper, we should also pay attention to the smell and taste of it. You can try pouring and soaking the filter paper, like what James Hoffman did in his video. Poor filter paper is likely to have a strong paper taste with wood pulp, leather, or even nauseating artificial chemical tastes, that brings sourness, spiciness, bitterness and so on.
Read more: The Magical Power of a Filter Paper
You can choose the appropriate filter paper with indicators like Brix, TDS and pH value. For example, most filter papers have a pH value of 7.6 or above.
This is a decisive factor. If you are just looking for an experience of hand-drip coffee, probably, the cheaper the better. The most convenient way is to buy them in the supermarket, where they usually got a great deal!
If you are aiming for a better coffee with more detailed taste, or if you’ve got some excellent quality beans that you don't want to destroy, you deserve a high-quality filter paper! Afterall, a cup of excellent specialty coffee is not a low-cost experience.
8. Personal taste
Do you like bright fruity acidic taste?
You can choose filter paper with high water permeability.
Do you like bright and oily coffee?
You can choose low-density filter paper.
Do you like rich and aromatic coffee?
You can choose filter paper with low water permeability and high density.
I personally prefer Cafec's filter paper, because I admire their devotion to developing their filter paper. Few companies in the coffee market do this, but Cafec Japan is the world's first company to develop cone-shaped filter paper. They have been investing and researching for almost 50 years in pursuit of the best filter paper.
“Paper, but not just paper.”