The Many Ways to Produce Coffee

From smallest to coarsest grind.

‘Turkish Coffee’ – traditionally served in an Ibrik
Turkish coffee is the common term for a specialized coffee made in Turkey, the Middle East, and Arab countries.  Known as kahve, the Arabic word for coffee, Turkish Coffee has multiple names such as Egyptian Coffee, Lebanese Coffee, and even Muddy Coffee, its Armenian name.

While there are numerous varieties of Turkish coffee throughout the world, the typical Western version of Turkish Coffee is produced in an ibrik (e-breek), a small narrow topped cooper pot.  In Turkish, this pot is called ‘ibrik’ and ‘cezve’ (chez-vuh), and in Greek, it’s called a ‘briki and ‘mbiki.

Turkish Coffee is made by pouring cold water into the ibrik, and then typically sugar and spices such a cardamom.  Finely ground coffee is added and the mix is then stirred until the sugar is dissolved and the grounds sink.  The spoon is removed, and the pot is then placed over a fire, burner, or flame.  The ibrik is then removed just as the coffee begins to boil.  If done properly, a thick foam is created on the top of the coffee (produced by the reaction of the cold water and coffee gradually warming to the boiling point) and the coffee will not get to a rolling boil.  The coffee can then be served, or may be double or triple ‘boiled’ over a lower heat setting.  The coffee is then served immediately into small cups not allowing the grinds to settle, or the ibrik is left to let the grinds settle while the foam is transferred via spoon to each cup.  The coffee is then poured slowly out of the ibrik allowing the bottom ‘sludge’ to remain.

Espresso
Espresso is an extraction method creating a unique ‘shot of coffee’ made by forcing temperature regulated water through finely ground coffee at approximately 9 bars (or atmospheres) of pressure.  Espresso has a thicker, more concentrated consistency and a higher number of dissolved solids than drip coffee, and is often wrongfully interpreted by consumers as being ‘stronger’ than drip coffee.

Measures in shots, which are in turn measured by the ounce or in milliliters, espressos signature characteristic is its crema, a layer of reddish brown foam that is produced due to the pressure the grounds are placed under during extraction.  This crema is made of the natural oils and sugars of the bean and retains the majority of the flavor found in an espresso shot.  Due to the unique characteristics of espresso and its concentrated form, espresso is often used as a base for other drinks such as latte’s, cappuccino’s, and mocha’s.

Espresso production requires specialized equipment.  Espresso machines heat water to exact temperatures, and when asked, push a perfectly proportioned amount of water at a regulated pressure through ground coffee causing the grounds to react unlike any other steeping method.  This exact pressure and temperature is what creates the coveted crema and flavor profile espresso is known for.  However, due to its special nature, espresso is highly susceptible to oxidization in the open air (similar to an apple turning brown shortly after it’s cut open).  Espresso must be used very quickly or the flavor will spoil.

Drip Coffee
Drip coffee is the most common and most economical extraction form used in the United States. While drip coffee can be made in numerous ways using various devices, all drip coffee methods are basically similar.  Water is heated (either by hand or automatically by machine) and poured over medium ground coffee contained in a paper, cloth or metal filter; the grounds then steep for a short amount of time while the coffee drips through the filter into a holding vessel that may or may not be electrically heated (heating coffee from an external source such as a warming plate after it is made is highly unrecommended!  Altering the natural temperature of coffee, up or down, can easily affect its flavor!)

While economical and easy to produce, drip coffee does not typically produce the highest quality coffee.  Coffee oils and fine particulate play a large role in the flavor profile of a good brew, and in drip coffee, especially when paper filters are used, these oils and particulates are often filtered out leaving a sub-par product.  The introduction of metal filters have helped this problem immensely allowing these to filter into the serving vessel and thus into your cup.

There are various drip coffee filters that can be used depending on the type of equipment used in making drip coffee.

  • Paper:  Paper filters are the most common used although often are not the best. Paper absorbs the important oils of coffee and do not allow the fine particulate to pass into the cup. Depending on the type of paper used, whether bleached or not, various flavors can pas from the filter into the coffee.  Even cheaper natural filters can impart a cardboard taste.  Environmentally, using natural filters are usually deemed better however many white filters are now whited using oxygen and not bleach itself.  And of course, while clean and easy to use, using paper filters of any kind does not necessarily help the growing garbage heaps outside our cities.
  • Metal Mesh:  Metal filters cure many of the issues in using paper filters. They are not thrown away and they allow more of the oils and particulates to drain through into the coffee.  Metal mesh filters typically come with varying sizes of holes so it’s important to test your filter to ensure your grind size is appropriate.  Mesh filters are also used in many French presses.
  • Plastic Mesh:  Plastic mesh filter screens often are used as an alternative to metal filters in low-cost machines and French presses.  Depending on the quality, they can have a tendency to break and melt, and often are responsible for imparting a cheap plastic taste to coffee.
  • Nylon Mesh:  Nylon mesh is similar to plastic however due to its flexible nature, it often filters smaller sediment easier and does not impart a taste.  Nylon is often used in tea filters, vacuum pots, and French presses.
  • Cloth:  Cloth filters are rare although they are washable and reusable.  Thick cloth filters are sometimes found in drip machines where a large amount of coffee needs to be filtered.
  • Glass:  While popular in the mid 20th Century, glass filters have become more antique than anything else.  While they functioned well, they obviously have the tendency to break and chip, potentially leaving glass in your coffee.  Many useable glass filter systems can be purchased online and thru antique stores, all of which make for an unusual conversation piece at yur kitchen table.

There are numerous extraction methods for producing drip coffee:

  • One cup brewers:  One cup brewers do exactly as they say…they produce one cup at a time.  They are in essence, the manual filter basket assembly of an auto drip machine.  The user places a paper or metal filter inside the brew cone, adds coffee, and then pours water into it, allowing the coffee to filter directly into the cup.   Larger models called Filter Cones are used when making batches larger than one cup.
  • AutoDrip:  These automated machines do one thing very well…they automate the brewing process for quick ease of use.  Consumers must be careful however in using these machines.  While there are high quality machines on the market, cheaper versions often do not heat and maintain the water properly, are inconsistent, use heated plates to ‘cook’ the coffee once made, and can produce a lot of paper waste if mesh metal filters are not used.  The best models have enough power to properly heat and maintain the water hot enough, and use thermal carafes instead of heating plates to keep the fresh coffee hot once filtered.
  • Chemex or hourglass brewers:  Hourglass brewers such as Chemex, the most popularly known kind invented in the 1940’s, are fun ways of making drip coffee while giving a fun science lab appearance.  These hourglass coffee makers use coarsely ground coffee and are simply made from large flasks and funnels using a special thick paper or cloth filter that can be washed and used repeatedly.
  • Single Serve Pods:  Some of the newest coffee technology has come in the form of pre-packaged single serve coffee pods.  Many are made with a small amount of hermetically sealed liquid coffee concentrate in a special small pod that is placed into a machine and then punctured and mixed with hot water to produce a single cup of coffee.  While the quality can vary, overall these options often produce better quality than many low-end coffees and the technology in producing these pods are increasing in quality every year.  This method is also very easy to use and clean allowing many commercial businesses such as hotels and banquet halls to provide a decent product without unnecessary labor.
  • Toddy coffee:  Often called the Cold Water process, toddy coffee is a way to make a smooth and non-acidic coffee concentrate.  A large amount of coffee is added to cold filtered water, and then left at room temperature or in a refrdigerator for approx. 12 hours.  The thick brew is then slowly filtered through a thick filter leaving a clean and smooth coffee concentrate behind that can be then kept for days.  This concentrate is then added to hot water to make drip coffee allowing the user to dial in their own strength of their individual cup.  Since coffee reacts differently when cold steeping versus hot, toddy coffee has very low acid levels, a trait many people require due to stomach issues.

French Press:
French press is commonly known as one of the highest quality ways to produce coffee.  Using a rather course grind, coffee is placed into a preheated French press pot (made of glass, plastic, or stainless).  Hot water is added to ensure all grounds are saturated and the lid with press attached and in the up position is placed over the container.  The coffee then steeps for a number of minutes, usually about 5 minutes depending on the coffee and grind used.  The plunger (the best are made of a high grade stainless steel or nylon mesh) is then pressed through the coffee allowing virtually all the oils and fine particulate to remain in the coffee itself creating a fully flavored cup.  Depending on the quality of press and how you are presently using it, the coffee can then be removed from the pot, or taken on the road if your French press doubles as a portable mug.

You must be careful when using a French press.  When pressing, if the plunger stops, do not apply excessive pressure to the plunger but rather slightly pull back on the plunger and start again (using excessive pressure could either shatter a glass press or break the seal on a non-glass press and cause hot coffee to squirt out the top).  If it still does not plunge properly, the screen itself may be plugged due to fine powder from the grinding process (in this case, check your grinder for proper operation)…try swirling the pot in a circular pattern a few times to loosen the grounds and try again.  In all cases, if you cannot get the plunger to properly plunge, do not force it!  Pour off the coffee you can, remove the plunger and check for obstructions or the obvious cause of the issue.

If done properly, a French pressed cup of coffee will deliver a top quality product.  The best presses are made of stainless steel and often double walled, thus ensuring heat loss is minimal.  High grade stainless also does not impart a taste such as plastic and does not stain so be sure to invest in a quality press if you want a quality and consistent cup.  Glass presses do not impart taste and are easy to clean however they crack and break easily, and have extremely low heat retention, a large flaw in the coffee world.  Plastic presses are lightweight, do not break, and are often inexpensive however they can impart a plastic flavor into the coffee and can often become very stained.

Vacuum Pots:
Vacuum pots are among one of the oldest forms of coffee making.  A cross between a drip maker and percolator, modern vacuum pots are made of glass or plastic and all work off the same basic principle.

For a traditional glass pot, a lower section is filled with water, and an upper section in the shape of a bowl is placed on top of the lower basin creating a seal.  A long tube then runs through the top section into the lower section close to the bottom.  A filter is placed on the top of the tube inside the top bowl, ground coffee is placed in the bowl, and the entire maker is then placed over a heat source.  As the water heats, air pressure inside the sealed lower unit (not produced by steam) forces the water thru the tube up into the upper section where it saturates the grounds and starts the steeping process.  Once the majority of water moves into the upper section, the heat is lowered to allow the coffee to properly steep.  The unit is removed from the heat source allowing the bottom section to cool.  As it cools, the pressure drops, pulling the coffee down into the lower section which acts as a serving carafe, leaving the grounds in the upper section.

Moka Pot:
Moka pots, or caffetterias, are often referred to as a metal stovetop espresso maker since they use pressure to produce coffee.  While similar in some ways, this is not completely accurate since the moka pot uses boiling water and steam pressure (which an espresso machine does not use), much like a percolator, to produce its coffee extractions.

While there are many versions of moka pots, and even some that steam milk while making coffee, there are three main parts.

  1. The lower part, often called the boiler, holds the water. This section has a pressure release valve attached to it.
  2. A funnel shaped filter and screen is then placed on top of the boiler and finely ground coffee is added.
  3. The upper section is screwed tightly onto the lower boiler creating a seal between the sections via a gasket.

The pot is placed over a heat source and the water is then boiled creating pressure inside the boiler.  A gasket between the upper and lower section ensures the seal remains tight while the pressure builds, and the safety release valve is there in case pressure gets too high.  The steam eventually reaches a high enough pressure to force the boiling water thru the funnel filter, through the grounds and then up into the upper chamber.  When the lower chamber is empty, steam bubbles mix with the uprising water and cause a signature gurgling noise.  In the best case scenarios though, the pot would not be left on the heat source long enough to cause this gurgling.

While moka pots can make a good quality strong coffee, they do require some upkeep.  The gaskets must be changed as necessary and the release valves must be checked periodically to ensure they are not blocked.  When using an aluminum pot, the residue left behind after use is often not cleaned and removed, thus protecting the coffee from contact with the aluminum which could impart a metallic taste.

Percolators:
Percolators were widely popular due to its mass marketing campaigns after WWII, and are nostalgic with people who grew up in the 40’s, 50’s, and 60’s.

Percolating is an extraction method caused by steam pressure.  A percolator is a metal pot that holds water, into which a long tube connected to a metal perforated filter basket at the top end is placed.  Very coarsely ground coffee is added to the filter, and the pot is sealed shut.  The water is boiled and is forced up the tube and into the grounds (this ‘percolation’ was often visually seen through the glass top of the pot).  The coffee then drips through into the bottom of the pot, is reboiled and repeatedly pushed up the tube and into the grounds, causing a circular cycle inside the pot that constantly is steeping the coffee at very high temperatures.  (Note:  modern electronic percolators do not allow the water to continually boil)

Percolators do not produce a quality cup of coffee.  The water is boiled and overheated, the coffee is extremely overextracted causing an extremely bitter taste, and the percolating action actually dispenses much of the all important and complex aromas into the air when they really need to stay in the coffee.  This signature aroma however is often fondly remembered by the older generation and is one of the reasons percolating often triggers positive memories.

Instant Coffee:
Instant coffee was invented originally in 1901 and launched as Nescafe in 1938.  Instant coffee is made by brewing coffee, and then evaporating the water off to produce a concentrate.  This concentrate is then frozen and placed in a high vacuum environment.   The vacuum is typically then warmed by radiation, conduction, or convection causing the previously frozen water in the coffee granule to expand to ten times its previous volume.  This water vapor is then condensed in the dryer and the remaining freeze dried coffee is ready for packaging.

Instant coffee can also be made by spray drying, where very fine streams of coffee concentrate are sprayed into very hot dry ovens causing the water to evaporate instantly.  The coffee is often mixed with other coloring and flavoring agents and powders to resemble coffee grounds.

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