Coffee filter

Paper filters remove oily components called diterpenes (like cafestol and kahweol). Coffee filters are typically made up of filaments approximately 20 micrometres wide, which allow particles through that are less than approximately 10 to 15 micrometres. Some baristas claim that paper filters exhibit a "paperish" taste and recommend washing out the filter with a flush of hot water before filling the ground coffee into the filter. Since paper filters filter out some components the resulting coffee is said to taste somewhat fruitier compared to permanent filters. For a filter to be compatible with a filter holder (in the case of drip coffee preparation also called a dripper) or coffee maker, the filter needs to be a specific shape and size. == Disposable paper filters ==

History of paper filters In 1782-79, Johann Georg Krünitz described a then-new method to extract coffee utilizing blotting paper in a (tinned) metal filter cone shape like. introduced their (English: quick filter), Patented in 1935, that is why other manufacturers use terms like coffee filter, paper filter, etc. In 1936,), "102" (for 3–6, or 4–8 cups or 10–15), "104" (for 15–25 or 30–60 cups), "112" (for 2 cups, with pot mount) and "123"). The system also included special types like tea filters "401" (1–6 cups, compatible with "101") and "402" (for 3–9 cups, compatible with "102") and the miniature filter "801" (for 1–2 or 1–3 small cups for children, or 1 normal cup A disadvantage of the system was that one had to pour water continuously or several times while the proper amount of necessary water could only be guessed. Therefore, in 1963 Melitta developed a new fan- or boat-shaped filter system with corresponding "1×" nomenclature: In this system the filters are sized big enough so that the whole amount of water (except for the water needed for blooming) can be poured in one go. Consequently, the filter sizes "1×2", "1×4", "1×6" and "1×10" result in 2, 4, 6, and 10 cups of coffee when filling the filter once. Since these filters only differ in height and have otherwise the exact same geometry, bottom width (about 49 mm) and angle (about 54°), the filter bags are interchangeable between filter holders of different sizes. Both systems are still in use today in principle, but the sizes "101", "103", "104", "105", "106", "112", "123", "401", "402", ("502",) "801" and "1×10" are no longer manufactured. Common in the US are fan- or boat-shaped filters "#0" (similar to "100"), "#1" (similar to "101"), Hario began designing brewers in 1980; the V60 design was released in 2004. The brewer received the Japanese Good Design Award in 2007 and is used by many of the winners in the World Brewers Cup. In partnership with 2013 World Barista Champion Pete Licata it was further developed into the Hario W60, a brewer with a flat-bottomed mesh filter, to "address the concern baristas have with 'flat bed' brewing". The Hario Switch combines steeping with drip filtering. Hario has cone-shaped paper filter bag sizes "01" (for 1 cup), "02" (for 1–4 cups) and "03" (for 1–6 cups). circle filter rings (for percolators) "3  in." (89 mm), "164mm", "190mm", "203mm", "235mm", "240mm", "244mm", "256mm", "260mm", "290mm", "330mm", "400mm" and "440mm", prepleated flat-bottom basket filters "(A)250/90" (250 mm/90 mm, also known as "90/250") and "(A)250/110" (250 mm/110 mm), roll filters "2004" as well as wrap filters (for percolators, 232 × 241 mm). While some of them are still available today, most of them have fallen out of use for long. A squarish pyramid filter Filtra "602" was available as well. Other basket filter sizes include "101/317", "152/350", "152/457", "203/533" and "280/635". Other round filter disks include 160 mm, 220 mm, 195 mm, 230 mm. The Aeropress and Ceado Hoop use round paper filter disks with a diameter of c. 63 mm. The German Tricolate coffee dripper uses round paper filter disks with a diameter of 88 mm. The Kanas-based NextLevel drippers use proprietary round disk paper filters as well (95 mm for the LVL-10 and 77 mm for the Pulsar). The Hario cold brew dripper Slow Brew "Shizuku" (WDC-6) and Water Dripper Clear (WDW-6) take 58 mm round filter disks. Chemex filter system The six conical filter holder sizes for the Chemex coffee maker (originally introduced in 1941) and the Funnex utilize two different sizes of paper filters. A half-moon shaped filter paper (bleached: FP-2, unbleached: FP-2N) is used for the 3-cup holders (CM-1, CM-1C, CM-1GH) and the Funnex (CM-FNX), which must be folded before use. The larger holders for 5 (CM-2), 6 (CM-6A, CM-6GH), 8 (CM-3, CM-8A, CM-8GH), 10 (CM-10A, CM-10GH) and 13 cups (CM-4) can alternatively use prefolded square sheets (bleached: FS-100, unbleached: FSU-100), prefolded circle filters (bleached: FC-100) or unfolded circle filters (bleached: FP-1). The paper is 20–30% thicker than regular paper filters. Other filter parameters and properties Other important coffee filter paper parameters are strength, compatibility, efficiency and capacity. If a coffee filter is not strong enough, it will tear or rupture, allowing coffee grains through to the coffee pot. Compatibility describes a filter medium's resistance to degradation by heat and chemical attack; a filter that is not compatible with the liquid passing through it is likely to break down, losing strength (structural failure). Efficiency is the retention of particles in a target (size) category. The efficiency is dictated by the particles or substances to be removed. A large-mesh filter may be efficient at retaining large particles but inefficient at retaining small particles. Capacity is the ability to "hold" previously removed particles while allowing further flow. A very efficient filter may show poor capacity, causing increased resistance to flow or other problems as it plugging up prematurely and increasing resistance or flow problems. A balance between particle capture and flow requirements must be met while ensuring integrity. == Reusable cloth filters ==

filter placed on a metal support in 1868. Reusable cloth (such as cotton, hemp, linen, silk, wool, hair cloth, horse hair, fustian, muslin or flannel) has been used to filter coffee for a very long time. Like paper, it strains out the coffee grounds, but the cloth filter allows more of the oil to come through than paper filters. An example of a cloth filter is the in Costa Rican chorreador coffee makers. == Permanent filters ==

Permanent filters can be divided into two groups: The first type integrates the filter sieve with the holding mechanism into one part. The second type of permanent filters are inserts to be used with a separate filter holder. For this, they are resembling the shape of disposable paper or reusable cloth filters otherwise used with those filter holders. Like them they can exhibit some amount of water bypass. Permanent metal filters are also used to prepare filtered coffee, including Vietnamese iced coffee and Indian filter coffee. The "French press" (also referred to as cafetière) uses a metal filter. Other types of permanent filters are made of plastic, porous ceramics, or porcelain (like the double-layered cross-slit strainer made from through-glazed porcelain of Karlsbad-style coffee makers or the special porcelain filter sieves of Büttner system coffee makers). == Filter holders ==

Filter holders are made out of plastic (including Makrolon/Exolon, Tritan, Ecozen), metal (stainless steel, copper, aluminium, emaille), ceramics, porcelain or glass, or rarely, wood. Melitta filter holders since 2018, or the Le Creuset dripper), anti-dribbling "tripod" plate design, design for simultaneous pouring into one or two cups (as for Melitta filter holders since 2018), double-walled design for better thermal insulation (as for Melitta Oslo Form 23 "102 M" filters, KPM Café Berlin LAB filters #2/#4, the Seltmann Weiden No Limits Barista filter #2, the Melitta 111th Anniversary Set filter 102, the Fellow Stagg X/XF drippers, the Chemex Funnex, the notNeutral Gino dripper, the Villeroy & Boch Coffee Passion V60 filter, the Brewista Tornado Duo filters, or the Etkin 8-cup and 2-cup drippers), radial water feeding (like with the Ceado Hoop), or a collapsible design for easier storage • accessories like a water spreader or cover lid or top-plate to help water distribution and reduce the temperature decline during pouring, a saucer to catch coffee droplets after use, a mounting stand, or coffee chilling stones. Metal and porcelain filter holders store more heat than glass or plastic filters and therefore should be pre-heated to avoid too large temperature drops during pouring. == See also ==