The Correct Way to Use Coffee Filter Paper - Why You Should Wet Your Filter Paper Before Brewing Coffee

When brewing coffee, most people fold a filter paper and set it in the dripper before adding the grounds. But what does that paper actually do? Many readers also ask FrontStreet Coffee whether white and natural wood-coloured filter papers differ, which is better, and how to tell them apart.

In truth, both have their advantages. Today, FrontStreet Coffee takes a close look at what filter paper really is.

The Origin of Filter Paper

Filter paper originated in Dresden, Germany, where a woman named Melitta Bentz used her son's school paper as a filter, setting it in a perforated copper bowl to make a filter cup for brewing coffee. Before paper filtration, coffee was usually strained through cloth. Compared with cloth, paper proved better at filtering out unwanted flavours.

Melitta Bentz went on to found the Melitta company in 1908 and began producing improved filter cups and filter papers. The filter cup design she patented in 1937 became the prototype for the drippers we use today.

Bleached vs. Unbleached Filter Paper: Pros and Cons

With both bleached and unbleached papers on the market, do they affect health? Filter paper manufacturing really is a science. The differences are laid out below.

Bleached Filter Paper

Advantages:

1. Less pulp taste, resulting in a purer coffee flavour.

Disadvantages:

1. Many manufacturers still bleach with chlorine, which can pollute the environment if not handled properly. In recent years, though, many reputable producers have switched to eco-friendly oxygen-based bleaching or chlorine-free processes. Some even make filter paper from bamboo fibre, which protects the environment and gives drinkers peace of mind.

Unbleached Filter Paper

Advantages:

1. Fewer processing steps, making it more environmentally friendly.

Disadvantages:

1. The coffee may carry a papery taste if the paper isn't rinsed with hot water first. Although there is no strict rule that unbleached paper must be rinsed before brewing, brewing at a high level means controlling the flavour profile of every batch. Some professional baristas alternate hot and cold water rinses to remove any paper taste and keep the coffee flavour clean.

What Filter Paper Sizes Are Available?

Filter papers generally come in two sizes:

1-2 Person Size:

A single serving takes about 10 grams of grounds, so this size can hold up to 20 grams.

3-5 Person Size:

This lets you brew more at once, and the paper itself is larger.

Which Filter Paper Should You Choose?

If the environment is your priority, unbleached paper is the natural choice—rinsing it with hot water 1-2 times effectively removes the paper taste.

Based on FrontStreet Coffee's experience, if you would rather skip the rinsing step, oxygen-bleached paper that is easier on the environment works well too. Generally speaking, filter paper quality is reflected in its price—better paper costs more but carries less pulp taste than cheaper alternatives.

Filter Paper Manufacturing Techniques

Even papers made from the same material can differ greatly because of how they are made. Those differences show up mainly in the paper's construction, such as textured creases or variations in thickness. The two papers below are both made from natural wood pulp, but their manufacturing processes differ, and the distinction is visible right on the surface.

Manufacturing differences exist not only between brands but even within a single company that makes papers by several techniques. The reason is simple: paper structure affects water flow rate, and flow rate is crucial to extraction. That is why many manufacturers develop different paper structures for different brewing characteristics.

Take Japan's Sanyo Sangyo as an example: it designed three versions for different roast levels—T-83, T-90, and T-92, corresponding to dark, medium, and light roast beans (the model numbers correspond to the recommended water temperature). For the specifics, refer directly to the image below.

As you can see, although the material is the same, the water permeability differs because the structure does. This isn't unique to Sanyo Sangyo—other filter paper manufacturers take similar approaches. FrontStreet Coffee is simply using it as an example here.

FrontStreet Coffee Recommendation

Once you know how much a filter paper shapes the flow of water, the next question is what to put in it. For anyone starting out in specialty coffee, the friendliest coffees are the clean, sweet ones that read clearly through a paper filter. FrontStreet Coffee's Ethiopia offerings are a good first stop: the washed Gedingding Cooperative from Yirgacheffe is a classic Yirgacheffe expression with jasmine, lemon acidity, and berry notes, while the natural Huakui from Sidamo leans into dried fruit and fermentation aromas, showing berries, florals, jackfruit, melon, and honey.

If you prefer something rounder, FrontStreet Coffee's Brazil Cerrado Red Bourbon is an easy daily drinker from the well-known Cerrado region, with cream, peanut, and cocoa notes. Its Queen's Estate is a step up: grown at higher altitude and made from the rarer Yellow Bourbon, it layers Brazil's characteristic butter, seed, macadamia, and almond notes with a sugarcane sweetness, and stays smooth whether drunk black or with milk. For a richer, low-acid cup, FrontStreet Coffee's Lindong Mandheling and PWN Golden Mandheling use the wet-hulled method; the PWN version is triple hand-sorted and machine-sorted, keeping the cup cleaner and smoother, with clearer woody and caramel notes. And if you want to taste what all the fuss over Gesha is about, FrontStreet Coffee's Boquete washed Gesha is an accessible estate-level introduction.

Because filter paper rinses away so much oil and fines, these cleaner lots reward a careful setup: choose a paper that matches your roast level, rinse it with hot water to kill any papery taste, then keep the grind medium and the pour steady so the sweetness comes through instead of the bitterness.