The Curious Barista's Guide to Coffee

by Tristan Stephenson

  Early references to coffee brewing in Constantinople refer to a copper ibrik, in which ‘powder’ is mixed with water once it ‘boyls’, then, once brewed, is ‘snatched quickly from the fire’ and poured into cups, leaving most of the grounds in the pot. An ibrik is a wide-bottomed pot with a spout near the top and a straight handle usually at right angles to the pot. This Turkish design was copied and improved once it arrived in Europe, and new iterations continued to appear in the 17th and 18th centuries.

  A classic coffee pot is usually tall, with a spout emanating from the middle or near the bottom – a design element that aims to restrict the migration of grounds from the top and bottom of the pot into the cup. The taller the better, since lanky pots further increase the distance between the spout and the extremities of the pot.

  Pot-brewed coffee is not without its problems, though; grounds always find a way out and as the pot empties, the problem is compounded. Once the technology existed, the Turks got around this issue by simply grinding as finely as possible. Most of the coffee then sinks to the bottom as intended, but it easily swims through the spout when the pot is disturbed, resulting in a thick, muddy and over-extracted cup that evidently, in the Turkish manner, requires sugar and flavourings to become palatable.

  This recipe follows the traditional Turkish custom for brewing coffee and will make enough for two cups. It’s not going to be the greatest cup of your life, but it does make an interesting coffee drink, while breaking a few rules along the way.

  HOW TO BREW TURKISH COFFEE

  1

  Grind 30 g/1 oz coffee and place it in a pot, or ibrik. Add sugar to taste – around 15 g/½ oz should be fine.

  2

  Add 400 g (400 ml/13 ½ fl. oz) cold water and then 2 g/1/16 oz ground cardamom, if desired.

  3

  Stir everything until the sugar has dissolved. Heat the pot on a stove until the contents boil. The mixture will froth up at this point, so quickly remove it from the stove and give a quick stir.

  4

  Place the pot back on the stove and repeat step 3.

  5

  Boil for a third time, remove from the heat, but don’t stir. Pour the coffee into Turkish cups. Wait a few minutes before drinking.

  The traditional Turkish ibrik is one of the oldest coffee brewers, but it’s sadly lacking in the technical department.

  THE MOKA POT

  The moka or stove-top pot is often incorrectly identified as an espresso maker – it’s not, of course – only espresso machines make espresso. Another common misapprehension is that the moka pot always boils the brewing water, causing it to overextract the coffee, which results in a bitter cup. That being said, for many of us the moka pot will always be associated with over-extracted, black, sooty cups of coffee, masquerading as espresso.

  While I cannot deny that I have been served terrible drinks from moka pots, I must qualify that statement with the fact that the coffee produced in a moka pot can be excellent if the all the rules are adhered to. Come to think of it, the moka pot might be the single most misunderstood piece of coffee-related paraphernalia out there. Those who love, cherish and use one regularly are generally not using them correctly, and those who scorn them do so because they have only ever even served bad coffee from one.

  HISTORY

  The moka pot was first patented by Alfonso Bialetti in 1933 and sold under the name ‘Moka Express’, but didn’t become popular until after World War II. Constructed from aluminium, and featuring an iconic design, they warmed up quickly and became a low-cost and convenient option for the home user.

  The inner workings of the moka pot function according to the same principles as the pumping percolator, a forerunner to the syphon coffee maker and the grandfather of pressure-operated coffee brewers. In the pumping percolator, water is heated and then pushed from the base of the pot by steam pressure into a second compartment in the top of the pot, which contains the coffee and a filter. The water then percolates down (like any other filter system) into a third section in the middle of the pot, and can then be poured out through a spout. If it sounds complicated it’s because it is, but the pumping percolator was an almost completely autonomous coffee maker – not bad considering it first appeared around 1820.

  The moka pot is slightly different, in that it percolates up, by way of an inverted funnel that is submerged in water at the beginning of the process. Steam pressure builds in the headspace of the lower part, forcing the water through the funnel, up through the coffee bed, then out through the pipe in the top chamber. The first machine to brew coffee like this was invented in 1833 by an Englishman called Samuel Parker. However, it was Bialetti’s Moka Express that made this kind of brewer popular. In just over ten years the ‘Express’ sold 20 million units. It became the go-to brewer for home use.

  USING A MOKA POT

  Let’s get one thing straight from the start: if used correctly, a moka pot can make excellent coffee. There are a few considerations beyond the normal range that must be factored in, however.

  Moka pots come in a vast range of sizes, some of which are comically large, and others that are absurdly small. Beware of bigger pots, because unless you have a very big heat source to match it, they can take a long time to brew and are highly susceptible to overextraction. This is one of the major flaws in the moka pot: the bigger the pot, the longer the brew time, meaning that grind size must be increased for larger pots to avoid astringent and dull flavours from overextraction. Some moka pots overcome this by including a weighted valve that prevents the water from percolating up until the necessary pressure is achieved – it’s important to know whether your pot has this for the brewing process to be effective (see the following page).

  Beyond the normal balancing of brew water to coffee ratio, I would also advise that you brew to the maximum capacity of the pot. This is because the less water you put in, the more headspace, and the more headspace, the easier the water is pushed into the top chamber. The quicker the water goes, the lower the temperature it will be, since it has had less time near the heat source.

  You’re probably getting the picture by now: brewing with a moka pot is quite an art, but very rewarding when it produces great results. Go for medium to dark roasts in this brewer, perhaps a light espresso roast, even.

  BREWING COFFEE WITH A MOKA POT

  Makes: 2 strong cups (if using a 200 g/7 oz) capacity pot

  Brew ratio: 1:5 (200 g/7 oz: 1 litre/1 ¾ pints)

  Grind: Fine filter

  1

  For moka pots without a weighted valve, you should first boil your 1 litre/32 fl. oz brewing water in a separate pot. If your moka pot has a weighted valve, pour the cold water directly into the bottom pot. (A)

  2

  Weigh and grind 40 g/1 ½ oz coffee and place it in the filter. (B)

  3

  Fill the base of the top section with 200 g/ (200 ml/6¾ fl. oz) hot water and assemble everything together (note that the water level for any pot should never exceed the pressure release valve on the base of the pot). (C)

  4

  Place the moka pot on the stove set over a medium heat. Open the lid and keep an eye on the process, as the water boils and the coffee starts to appear. You can control the rate by lowering the temperature on the stove, which in turn controls extraction.

  5

  Listen and look out for any bubbling – this indicates that steam is coming through, and at this point, turn the heat off. (D)

  6

  Quickly run cold water over the outside of the pot to halt the brewing process.

  7

  Serve the coffee and allow to cool a little before tasting. (E)

  THE FRENCH PRESS

  In Europe, the French press, cafetière, or plunge pot is probably still the most common method of brewing fresh coffee at home. It functions like any other coffee pot, but with the addition of a plunger that drives a filter down through the brew water, coaxing all but the smallest insoluble grounds to the bottom of the pot. The French
press is a fantastic way to brew coffee, since it is a fully immersed brew that retains plenty of body in the coffee and is easy to control. The downside to the French press is the sacrifice of cleanliness and acidity that paper filter brewing does so well.

  HISTORY

  In 1852, a patent was filed in France for an ‘Infusion Coffee Maker’ by two Frenchmen, named Mayer and Delforge. The title of the brewer correctly identifies the key feature of this early brewer – infusion. Here was a coffee maker that allowed the user to dictate exactly how long the coffee was steeped for before removing the grounds, and therefore gave greater control over the flavour extraction. This early French press also granted a simple way to infuse and filter coffee in a single pot, without the need for a constant heat source or other paraphernalia.

  Unfortunately, the machine was flawed, since the technology at the time made it difficult to manufacture a moving mesh filter that successfuly clung to the sides of the pot. Coffee was muddy and the pot difficult to use. The principles were in place, though, and other pots followed, some using complex spring mechanisms and others incorporating a two-stage filtering process to remove finer grounds, not unlike the modern Espro Press. These days, the best press pots are made using nylon filters, which were first introduced in the 1980s, with secure-fitting rubber gaskets.

  USING A FRENCH PRESS

  The trick with a French press is patience and a gentle touch. The associated ‘sludge’ that can haunt the bottom of your cup is a sign of poor brewing technique and a result of fine grounds sneaking through the apertures of the filter. Almost all grinders produce fines (see pages 80–81), and there’s little that can be done about them other than sifting them out in a tea strainer after brewing. You can, however, limit the sludge by skimming the top, plunging the filter gently and allowing the brew to sit for a few minutes before pouring.

  If the sludge is still getting you down, you can always pass the brewed coffee through a paper filter before serving. You’ll lose some body from the coffee, of course, but the extraction ratio will remain the same and clarity will also improve.

  TIPS WHEN BUYING A FRENCH PRESS

  • Look for a French press that features a secure-fitting filter.

  • Bear in mind that steel pots will lose heat quickly unless they are double-walled.

  • In my opinion, nylon filters are generally better than metal.

  • Buy the smallest pot you can get away with.

  • Half-filling a large pot is bad practice as the material of the pot draws heat from the brewing water.

  BREWING COFFEE WITH A FRENCH PRESS

  Makes: 2 cups

  Brew ratio: 1:15 (66 g/2 ¼ oz: 1 litre/1 ¾ pints)

  Grind: Coarse

  1

  Preheat your French press with hot water (then pour the water away).

  2

  Set the French press on a set of digital scales.

  3

  Grind 22 g/¾ oz coffee and add it to the French press. (A)

  4

  Pour in 330 g (330 ml/11 fl. oz) hot water (B), then give it a quick stir. (C)

  5

  Allow to sit for a further 30 seconds.

  6

  Skim the orange foam off the top of the brew water with a spoon. (D)

  7

  Place the lid on top and begin gently pressing the plunger (E). If you feel too much resistance, slow down and/or stop for a few seconds.

  8

  Once the plunger is completely depressed, let the brew rest for 5 minutes.

  9

  Serve, pouring a little into each cup and then topping up – this ensures the even distribution of insoluble particles. Leave a little water in the pot.

  FILTER COFFEE

  Filters have been around for thousands of years, with even ancient Egyptian tombs depicting water-treatment filters as far back as 1500 BC. The physical filtering of coffee probably didn’t exist until the end of the 17th century, after coffee had become readily available in Europe. Not surprisingly, really, filters are technically very clever bits of apparatus, regardless of what shape or form they take. Industrialization helped make the filter more common, meaning that filter coffee didn’t truly become a reality for the common man until the turn of the 20th century. Typically the filter is made from steel, nylon, paper or cloth, but there have been many materials used as mediums for coffee filtering in the past, from cloths made out of woven horsehair, to silk, porcelain and hemp.

  Depending on where you come from, filter coffee can refer to an assortment of brewing methods – in many parts of Europe it simply means a black coffee, which is fair to an extent, since almost all brewing methods require some kind of filter. In this book, ‘filter’ is applicable to any type of brewing method where water percolates through coffee placed in/on a semi-permeable barrier using only the power of gravity. That is, no immersion, pump, vacuum or press is involved.

  Filter coffee, in general, is a reasonably easy and clean way to brew coffee at home. Coffee prepared in this manner requires a filter to hold the grounds, which itself is often held within another vessel, and a pot to collect the brewed liquid underneath. The weight of the brewing water forces the brewed coffee through a filter, which in turn drips or runs out of the bottom. Producing great results that are repeatable is more difficult than in a French press (see pages 120–123) or Aeropress (see pages 134–137), since it is much harder to control the infusion time. When brewing coffee this way the infusion is regulated by adjusting the speed at which the water is added to the filter, the amount of coffee used, and how fine or coarse the grind is.

  A NOTE ON POURING

  The way in which coffee grounds are wetted and agitated is of particular importance to filter brewing. Pouring technique will exert an influence over the brew time, turbulence and brew temperature, all of which affect the extraction of flavour. You may choose to use a pouring kettle, which aids in evenly wetting the coffee during the bloom and the remainder of the brewing steps, and provides a consistent, controllable flow of water.

  More water in the filter means a greater weight forcing the brewed coffee through the filter. More water also means a higher brew temperature overall, since it quickly heats up the brewing vessel to near the temperature of the brewing water. A material like aluminium, for example, has a high thermal conductivity and will quickly draw energy heat away from the brew if it isn’t preheated. Plastic, on the other hand, is a good insulator of heat and will keep the brew temperature quite stable. Conversely, an excessively slow pour means that your brew may struggle to reach an acceptable temperature (to best extract sweetness), and may loiter around in the filter for too long, potentially becoming bitter or overextracted. For more on brew temperature, see pages 68–70.

  Pouring in such a way that all the grounds are evenly soaked is crucial, too, and doing this in such a way as to agitate the coffee will improve the flow of liquid around the coffee, causing it to extract faster.

  A NOTE ON BLOOMING

  Blooming, as the name eloquently suggests, is one of the more delightful sights in coffee brewing. The bloom occurs when fresh coffee is first wetted by a splash of hot water, most commonly in filter brewing. As the ground coffee absorbs the water, carbon dioxide purges out from the bean and carbonates the brew mixture – yes, those bubbles are the same ones as you get in a glass of Coke. The effect is a curiously attractive belching and expansion of the coffee bed, often doubling in size in 10 seconds with very fresh coffee. Besides the visual gratification from witnessing coffee as a living, ‘breathing’ entity, blooming is actually thought to be an important part of brewing a good cup of coffee, especially in filter brewing.

  When carbon dioxide is purged from the grounds, it forms a tiny barrier of outward force between the brew water and the coffee grounds themselves. The gas is thought to impede the access of water to all the wonderful solubles held within the grounds, so by allowing the bloom to expand and subside a little, we are essentially displacing the carbon dioxide before adding the bulk of
the brewing water. In immersion brewing, it is questionable whether blooming the coffee actually makes much difference to the cup, as the mixture is usually stirred, but in filter brewing, wetting the grounds for 10–20 seconds is an important step to help with creating an even bed and even extraction of grounds during percolation.

  The Chemex coffee brewer has been a cult brewer for over 70 years, and even features in New York’s Museum of Modern Art.

  CLOTH-FILTER BREWING

  At its best, a cloth filter can produce a wonderful cup of coffee, benefiting from some of the mouthfeel of a French press brew, but without the muddiness that can sometimes haunt a French press. I’ve chosen to place cloth filters in a separate category to reusable filters, since they have a finite lifespan and they offer a very different style of brew compared to metal and nylon.

  HISTORY

  The first cloth coffee filters appeared some time around the beginning of the 18th century. They originally comprised either a separate filter attached to the mouth of a coffee pot, which ‘caught’ the grounds as they exited the apparatus, or a pot that held a muslin filter from its rim, acting like a giant suspended tea bag in some ways. The latter is also known as a ‘biggin’ – possibly a corruption of ‘bag-in’, or from the Dutch word beggelin, meaning to ‘filter down’. Biggin pots with cloth filters are now becoming rare finds in antiques’ markets, but there are plenty of the more modern enamel versions still knocking around.

  USING A CLOTH FILTER

  One of the main benefits of cloth filter over paper is that cloth allows the passing of flavourful coffee oils into the cup. The downside of the cloth filter is that fine grounds easily clog it up, so they can be difficult to clean and maintain. Once a cloth filter clogs up, bad things happen. The clogged cloth restricts the passing of coffee through the filter; in the worst case, this can completely stall the filtering process altogether, leaving the brew to overextract. Also, if the grind is too coarse, the water will pass through very quickly, so as always the degree of grind is very important here.