Do You Need Filter Paper for Pour-Over Coffee? What's the Impact of Not Wetting the Filter Paper When Brewing?

One day, when FrontStreet Coffee's barista was brewing both iced pour-over and hot pour-over coffee, a customer asked: "Why did one of you wet the filter paper, while the other started brewing directly without wetting it?"

Is wetting the filter paper a necessary step before brewing? If not, when should you wet the filter paper? Let FrontStreet Coffee explain the specific reasons.

Purposes of Wetting Filter Paper:

1. Cleaning the Filter Paper and Removing Odors

Some people might wonder 🤔️, aren't there already filter papers bleached with bioactive enzymes that are tasteless? As long as you buy reliable filter paper brands, this shouldn't be a concern, right?

However, everyone might overlook one point: how do you store your filter paper? What's the storage environment like? FrontStreet Coffee once encountered a friend who left filter paper open on shelves, but he was a heavy smoker who often smoked alone at home. One can imagine what the filter paper would become in that situation.

It can be said that "the success and failure of tasteless filter paper" lies in their very nature – tasteless filter paper actually absorbs odors more easily. Of course, if you store filter paper sealed separately, you don't need to consider this point.

2. Preheating the Dripper and Server

This point needs to be considered based on the material of your dripper. If you have a plastic dripper, it doesn't absorb heat and has poor insulation properties, so whether you preheat it or not won't significantly impact brewing. However, when you use a ceramic dripper, wetting the filter paper while preheating the dripper becomes very necessary. (For those interested in the insulation properties of dripper materials, you can click here)

Preheating the server ensures that when the coffee liquid is extracted, the temperature won't drop too much, allowing you to better taste the coffee's flavors.

3. Ensuring Better Fit with the Dripper

When you're not confident in your filter paper folding technique, you can press the filter paper with your hand while adding water to wet it. This can help ensure the filter paper fits more snugly against the dripper. Of course, if the technique is poor, or if the filter paper doesn't match the dripper, wetting it still won't achieve a proper fit.

If you want your coffee extraction to be more uniform and reduce the impact of filter paper factors, then the following three points about filter paper are worth considering more carefully.

1. Bloom and Gas Release

After wetting, the filter paper softens and adheres closely to the dripper. The grooves on the dripper cannot support the filter paper, which affects the effectiveness of bloom and gas release.

2. Pre-extraction of Coffee Powder After Wetting Filter Paper

"Extraction" begins the moment coffee powder comes into contact with water. If you pour dry coffee powder into a wet filter paper, the coffee powder near the filter paper will become moistened. Doesn't this cause some coffee powder to be extracted in advance?

3. Water Absorption Capacity of Filter Paper

A single filter paper absorbs about 8g of water. If it's completely wetted with water, the extracted coffee liquid won't seep upward, so after wetting the filter paper and brewing coffee, the filter paper appears nearly white. Without wetting the filter paper, coffee liquid will seep into the filter paper. This phenomenon is particularly noticeable when brewing dark roast beans – you can see the coffee-colored liquid gradually seeping upward.

Returning to the original customer's question, do you now understand why FrontStreet Coffee handles filter paper differently for hot and iced brewing?

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FrontStreet Coffee

No. 10 Bao'an Qianjie, Yandun Road, Dongshankou, Yuexiu District, Guangzhou, Guangdong Province

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473