Understanding Double-Chamber Filter Paper and Its Spanish Origins

Double-chamber filter paper is a unique pour-over tool designed by the Spanish brand Sibarist. It features a central dividing wall that splits the filter into two separate compartments, allowing you to brew two different coffees simultaneously. This concept, often called the yin-yang pot filter, originated from Spain's coffee culture and aims to let coffee beans with distinct characteristics each be extracted separately in a single brew. However, its high cost—37.44 euros for 30 sheets—makes it a luxury item.

For those who want to try this method without the expense, a DIY alternative is possible. By using two size 01 filter papers in a size 02 conical dripper, you can replicate the dual-chamber structure. When brewing, pay attention to water temperature and pouring technique to ensure even extraction on both sides. While the original filter paper is impractical for daily use due to its price, the DIY version offers a budget-friendly way to explore this innovative approach.

Front Street recently came across a uniquely shaped pour-over filter paper—the dual-chamber filter paper from Spain's Sibarist. Because its interior is split in two by a dividing wall, netizens have jokingly dubbed it the "double-flavor hot pot filter paper." The original design intent was to let coffee beans with different characteristics each be extracted separately in a single brew, but at 37.44 euros for 30 sheets, the cost per sheet is about 9.4 yuan, which is truly staggering for a disposable consumable. Front Street decided to make a DIY alternative version, using two size 01 filter papers in a size 02 conical dripper to replicate the dual-chamber structure, and to discuss the water temperature and other parameters that need to be considered in actual brewing with this kind of filter paper. This article will walk you through the construction principle of the dual-chamber filter paper, its official pricing, how to make the DIY alternative, and the core considerations when using it, to see whether it's worth buying.

Front Street recently noticed a filter paper that came out last year, and its design concept is completely different from common products on the market. How is it different? Simply put, when making coffee by pour-over, you can actually experience a "double-flavor hot pot" sensation. When this filter paper is unfolded, two independent cavities form inside, each of which can hold coffee grounds. Its shape is almost identical to the divided pot in a hot pot restaurant, so netizens have jokingly dubbed it the "double-flavor hot pot filter paper."

Its formal name is the Dual Chamber Filter, developed by the Spanish coffee equipment brand Sibarist. Compared with ordinary filter paper, its most notable feature is a "dividing wall" set in the middle, splitting the interior space of the filter paper into two halves. Based on the official demonstration video Front Street saw, this dividing wall is quite dense; during brewing, hot water poured into one side can hardly pass through the wall to the other side, so calling it a true "wall" is no exaggeration. Front Street originally wanted to order a pack to try, however...

30 sheets of dual-chamber filter paper are priced at 37.44 euros, about 283 yuan, which works out to 9.4 yuan per sheet! How many bags of coffee beans could that buy!!!

It's not hard to understand why there are almost no review articles for this filter paper online. For a consumable like filter paper that is thrown away after use, this pricing is indeed unreasonably high, and hard for ordinary consumers to accept. If you, like Front Street, are struggling over whether to spend so much on a single sheet of filter paper, then you might as well make a DIY alternative first to experience it and see whether the effect of the "double-flavor hot pot filter paper" really matches this price.

The method for making the DIY alternative is not complicated; you only need to place two size 01 filter papers into a size 02 conical dripper. Specifically, fold the two filter papers according to the usual steps, then insert them face-to-face into the dripper, and a DIY "dual-chamber filter paper" is complete.

However, if you want a more ideal isolation effect, one that can block coffee liquid from penetrating like the dividing wall in the official diagram, then you need to use non-woven filter paper made of special material, because when filter paper does not come into contact with coffee grounds, it is itself very difficult for liquid to penetrate.

But once we replicate the filter paper, we discover that the problems we then face are far more numerous than imagined. You might as well imagine online how such a distinctive filter paper should be used and how to brew with it. What should be considered when using the "double-flavor hot pot" filter paper? Obviously, the "double-flavor hot pot" filter paper was created so that beans with different characteristics (such as different roast levels) can each be extracted in the same brew. After all, if all coffee beans have the same profile, you only need to grind them and mix them together to brew; there is no need to deliberately separate them, which would be superfluous. But coffee beans with different characteristics require different extraction parameters, and among all these parameters, the one that most needs to be addressed is the water temperature issue.

The above content is compiled by CoffeeHunters, a coffee news website.