The Curious Barista's Guide to Coffee

by Tristan Stephenson

  But the truly authentic espresso bar, as Continentally quintessential as it may sound – where a 60-second visit grants one enough time to order, demolish, and pay for a drink without even taking a seat – has never truly found traction outside of Italy. It has been softened and adapted to meet the standards of the working-class man, business executive and lady who lunches (among many others) alike. In many respects the Italian roots of espresso have paled over the past 20 years, only to be replaced by a new style of coffee appreciation that, rather alarmingly, has little to do with actual coffee (although they would have you believe otherwise).

  Growth of the American-style coffee chain, born out of the West Coast anti-establishment and wholefood movement of the late 1960s, still pushes on, and the likes of Starbucks now adorn not only the towns and cities of the western world, but the rest of the world, too. The commercialization of ‘milk and sugar coffee’ has in fact reached such a point of ubiquity that, some would say, the cities of our world are quickly becoming carbon copies of one another, with the same inescapable shop fronts (and café interiors) wherever you go – ironic, given the motivations behind their humble origins.

  This kind of success doesn’t come without being popular, however, which means that, for many of us, the prevalence of such places is a positive thing. The most obvious reason for this is the function that they serve as a ‘third place’ between work and home: one which is reliable, unchanging and accessible wherever you are. While some of the individuality may be lost in these chains, in many respects they are the same as those of the 17th century, acutely aware of and cleverly balancing the dual purpose of being both a place that coffee can be enjoyed and somewhere where higher cultural values can be appreciated. Think about it: a seat in Starbucks grants one access to a forum for any kind of discussion, limitless creative space, research tools for the sciences and arts, media libraries and cutting edge news – all you need is a laptop and a WiFi password. Coffee is optional, as the Starbucks’ logo would attest to; once proudly stating ‘Starbucks Coffee’, it now makes no mention coffee at all.

  One major development of the past 20 years is how discerning in our ordering rituals we have become. The element of choice in a café has become a expressive device with which we can communicate personal taste and product understanding in an otherwise homogenized high-street environment. The coffee menu at a typical chain store offers maybe six varieties of drink, four types of milk, two or three espresso sizes, half-a-dozen flavoured sauces and three beverage sizes, totalling well over 1,000 different permutations. The trick is in the demystifying design of the menu, which seeks to process and output our order as rapidly as possible. Of course our decision is more often made before we even walk in, but even when some deliberation occurs, it is surprising how rapidly we can trim 1,000 options down to a single order.

  And now it is the notion of removing choice – which only a short time ago was celebrated by the world’s best cafés – that defines the new wave of quality-driven hipster hangouts. In these minimalist inner-city sanctuaries, we see the counter-culture movement once again partnering with coffee, where quality, knowledge and attention to detail are the overriding themes (sometimes at the sacrifice of good service) and excellent coffee the backbone. Many of these cafés hold their product in such high regard that they will roast their own coffee, directing consumer decision-making specifically to the brew method and the origin and processing method of the coffee. In most instances, it is expertise of the barista in which we place our trust, which broadens the dynamic further. In this way the entire concept of a cup of coffee evolves from being an indulgent treat, caffeinated pick-me-up or expression of individuality, into a beverage that contains all the nuance and refinement of a fine wine or gourmet steak, naturally drawing attention to our apparent appreciation of such things in the action of drinking it.

  Where cafés will go next is difficult to say, but it will no doubt be beneficial to everyone. Certainly it would appear that the large chains are becoming increasingly influenced by the focus on provenance and traceability of the smaller, craft-focused independents; improvements among the large chains in the areas of training and quality should follow. If I were putting my neck on the line, I would argue that many of the independents could learn a lot from the customer service standards of some of the chains, especially in the US. Some cutting-edge coffee shops have succumbed to a certain elitist attitude, validated by their belief in their own superiority through the acquisition of coffee knowledge, which can come across stand-offish – ‘You want the golden-honey pacamara brewed in siphon?!’ – or just plain rude. I hope to see this weeded out in the coming years.

  Craft, transparency and skinny jeans are the three pillars that support the new wave of cafés.

  GROWING, HARVESTING AND PROCESSING COFFEE

  02

  SPECIES AND VARIETIES

  Coffee grows on trees – coffee trees. It may seem like an obvious distinction, but one that is worth making. All coffee trees belong to the Rubiaceae family of flowering plants, and more specifically, the Coffea genus, which currently encompasses over 120 individual species of plant, ranging from small shrubs to 18-m/60-ft high trees. Coffea species grow wild across various parts of the tropics and new species continue to be discovered. Strictly speaking, only two species of the Coffea genus are actually cultivated for coffee production: Coffea Arabica (arabica) and Coffea Canephora (commonly referred to as ‘robusta’), but there are a handful of countries, such as the Philippines, that grow small amounts of a third species, Coffea Liberica, for domestic consumption.

  Around 70 per cent of the world’s commercially grown coffee are varieties of arabica, which adds up to about 7 million tons of roasted coffee every year. The rest grow robusta, most of which comes from India, the Indonesian islands of Java and Sumatra, and Vietnam, the latter of which produces nearly half of all the world’s total output of robusta coffee and is the second-biggest coffee grower after Brazil.

  As the name suggests, robusta is the more disease-resistant of the two main species, and this is in part due to its higher caffeine content, which acts as a deterrent to small pests. Robusta typically yields comparatively more fruit per harvest, plus its ripe fruit hangs on the tree and withers, unlike arabica, which must be picked before it falls onto the ground. Robusta produces a smaller and less elongated bean than arabica, and it generally possesses a stronger, albeit less desirable flavour. It’s for this reason that robusta is often used as a small part of espresso blends, prized by the Italians in particular for its ability to produce an impactful shot, with good crema (see pages 96–97) and plenty of caffeine.

  You might then wonder what benefits arabica can offer? Flavour is, of course, the answer; the arabica plant produces a more nuanced product and its varieties are broad, well-defined and characterful in both their appearance and the styles of coffee that they produce. Most varieties are mutations or cross-breeds of two godfathers of arabica coffee – typica and bourbon. Typica (often simply referred to as arabica) is the variety of coffee that was first transported from Ethiopia to Yemen, then on to India. In 1718, typica samples from Java were transported to the French island of Bourbon (now known as Réunion) that lies 800 km/500 miles east of Madagascar, in the Indian Ocean. Here they mutated into a new variety, which was subsequently named bourbon. Bourbon and typica varieties now encompass the lion’s share of the many varieties of arabica coffee that we see in today’s coffee market.

  A 19th-century colour engraving of the Coffea arabica species, clearly showing the fruit, flower and seeds of the plant.

  Some of these varieties are born out of natural mutation and others are the product of the intentional cross-breeding or selection of heirloom varieties. Arabica is a self-pollinating species, so by rights the family bloodline should remain pure. But as typica and bourbon were transported to new countries and exotic climates, natural mutations took place and many of these new variants were cultivated for their desirable features.

  An
arabica tree in Mexico, decorated with a full spectrum of underripe (green) and ripe (red) fruit.

  The story of robusta is a similar one, although the species was not officially classified until 1895 (arabica was classified in 1753). Robusta is native to Western Africa, and from there it spread throughout the world via Java. Like arabica, there are many varieties within the robusta species, but it offers little to get excited about, flavour-wise. On that note, from here on I will refer only to arabica varieties when talking generally about coffee, unless otherwise stated.

  ANATOMY OF THE RAW COFFEE BEAN

  Inside the coffee fruit or ‘cherry’ are the flat-sided kernels, which are technically seeds, but are more commonly known as beans. In each cherry, there are usually two, but sometimes – and especially on trees grown in soil containing low quantities of the micronutrient boron – there is only one, which is known as a peaberry.

  Peeling open a coffee cherry usually reveals a pair of seeds surrounded by slimy mucilage.

  ‘Green’ or unroasted coffee beans, like most seeds, are compact stores of carbohydrates, proteins, acids and fats – basically everything the plant needs to grow and mature. Carbohydrates provide the energy that the bean would otherwise use, and makes up approximately 50 per cent of the total mass of the processed green bean. Approximately 10–20 per cent of that carbohydrate is sucrose, which will go on to provide sweetness, bittersweet caramels and even acidity later on when roasting. There’s a good store of fats and proteins, too, the latter of which will react with sugar during roasting (known as Maillard reactions) to create the familiar browned appearance and corresponding flavours that we know and love.

  Caffeine (a type of alkaloid) is naturally present at a level of 1–2 per cent, plus there’s the lesser-known alkaloid, trigonelline, which makes up approximately 1 per cent of the bean’s dry weight. Trigonelline contributes a great deal of complex bitter notes to the coffee through the chemical effect of roasting, including niacin (vitamin B3).

  Finally, there’s a whole host of organic acids that give us both acidity and bitterness; most important among these is chlorogenic acid (CGA), which makes up around 8 per cent of the dry mass of a green bean.

  GROWING AND HARVESTING COFFEE

  Virtually all of the coffee trees in the world can be found in the tropics. The typical lifespan of an arabica plant sees the plant mature from tiny seedling (or ‘soldier’) to flowering stage after three to five years. Shortly after it flowers, it will begin to fruit, which takes from 9–11 months to grow and ripen, and generally announces its readiness by turning a shade of vivid pinky red – although there are some varieties that produce a yellow- or orange-coloured fruit when ripe.

  Coffee trees like wet, humid and shady environments, and the arabica tree in particular is sensitive to wind and high temperature. For this reason, it tends to be grown at higher altitudes; the sweet spot is usually somewhere between 1,000–2,000 m/3,300–6,600 ft elevation – any higher and the risk of frost increases.

  Some arabica and robusta varieties will grow many metres high if left to their own devices, so constant pruning is required to bush out the bottom of the plant and secure the position of the fruit at an accessible height for pickers – although it’s not unheard of for farm workers to use ladders.

  Rather unhelpfully, coffee trees flower irregularly, resulting in ripe and unripe fruit adorning the plant at the same time. Consequentially, the mechanical harvesting of coffee in most countries is rare, and frowned upon, since it wastefully strips the tree of both ripe and unripe fruit. Couple that with the fact that many coffee farmers cannot afford to purchase such machines, as well as the difficulties presented by the invariably hilly coffee growing terrain, and it becomes very apparent that coffee farming is a highly laborious and literally ‘hands-on’ profession.

  A coffee plantation near the south-western city of Jima, Ethiopia. Until it was dissolved in 2007 this region was known as Kaffa, and thought by some to be the birthplace of coffee.

  There are exceptions, however, and in this instance it’s a very large exception. In Brazil, coffee is mostly harvested en masse, using either machines that strip both ripe, overripe and underripe fruit at the same time, or by simply shaking the tree and catching all the fruit on the ground. This slightly wasteful process is born out of a culture of quantity, not quality, farming (there are, of course, exceptions) that Brazil has become infamous for. A hundred years ago, Brazil produced over three-quarters of the coffee in the world, today it accounts for around one-third, which, at around 300,000 farms and 4 billion trees, is still an eye-watering amount.

  Hand picking is not without its issues either. Some farms still insist on picking everything available and sorting it later, and even on farms that make multiple passes of the same trees, the simple instruction to pick ripe fruit is ignored as most pickers are paid by the weight of coffee they harvest. For this reason, many coffee pickers tend to grab fruit that is still a little underripe. Direct trade between roasters and farmers, where two-way communication aims to maximize the quality of the roasted product, is improving this, however, as the message that ripe fruit makes better coffee is repeatedly hammered home. In light of this, there are examples of pickers receiving rewards for harvesting ripe fruit only.

  A single arabica tree can produce between 3–5 kg/6.5–11 lbs of ripe fruit in a single season, if all the elements of climate and care come together nicely. The higher end of that scale roughly equates to 1 kg/2.2 lbs of roasted beans, or 110 single espressos. Labour costs vary from country to country, but in some Central American countries, a good harvester might be capable of picking 100 kg/220 lbs of fruit in a single day, which would earn them approximately £6.50/$10, which works out as less than half a penny/half a single cent per espresso. Some coffee pickers are paid even less.

  Direct trade is probably the single biggest driving force behind better-quality green beans and ensuring a fairer price for them. Take Ricardo Barbosa, for example. His farm, Fazendas Mariano, in Minas Gerais, Brazil, began supplying Origin Coffee in the UK four years ago. At the time, Ricardo consulted an agronomist to improve the running of his farm. Year on year, the quality and yield of the farm has improved and Fazendas Mariano now sells its coffee for almost $1 over the market level per pound.

  This soldier plant will need at least another three years of maturation before it begins producing fruit.

  Workforce management plays a big part in this, too, where often the picking season is relatively short and the pickers aren’t full-time employees. Clever solutions to this problem are being developed, however. In Nicaragua, for example, coffee is grown on plots known as tablones which, due to their terroir, will cause fruit to ripen at slightly different times of the season. This allows efficient management of the pickers, who can move from one plot to another during the harvest period. In many mountainous countries, coffee is grown at altitude, where it benefits from low humidity (which lowers the risk of mould and mildew) and cooler temperatures, before it is dried and processed at lower heights that are more suitable for this part of the process. In Guatemala, for example, an altitude shift of 300 m/1,000 ft can equate to a temperature difference of as much as 5°C/41°F.

  Once picked, all of the fruit goes through a machine that screens the picked cherries. Overripe (black) fruit floats, underripe (green) fruit falls through small apertures, and red (ripe) fruit is retained by the machine. Then, the green fruit is allowed to ripen off the tree – on a patio, for example – and eventually dried and processed naturally. The red fruit is usually pulped before further processing and the already-dried cherries are sent immediately for processing. Essentially, nothing is wasted, though it’s generally understood that off-the-tree ripening results in a poorer-quality coffee.

  COFFEE LEAF RUST

  Hemileia vastatrix, also known as ‘coffee leaf rust’ is a fungal parasite that targets all Coffea species. It blackens leaves, causing them to fall off and stripping the plant of most or all of its leaves. It was first re
ported in Kenya in 1861, and had, in just a few years, travelled to Sri Lanka (then Ceylon) and very nearly decimated the entire industry there.

  Today, coffee rust is as big a problem as it has ever been. Ever-increasing temperatures and higher humidity brought on by climate change are thought to have aggravated the problem and it continues to affect not only the livelihoods of farmers, but in some cases the economic stability of entire countries. In 2013 Honduras, El Salvador and Guatemala all declared a state of national emergency during a bout of coffee leaf rust, some of them having to contend with the blighting of 70 per cent of their total crop. It looks to have hit just as hard in 2014, with Nicaragua feeling the full force of the impact.

  Coffee leaf rust can be completely devastating, not just for the welfare of individual farmers, but also in terms of a country’s economic output.

  Such is the severity of the problem that the American Phytopathological Society recommend that coffee leaf rust should be treated as a ‘continuous epidemic’. Some copper-based fungicides have proven effective in both protecting from the disease and improving fruit yield, but are largely cost-prohibitive, must be reapplied regularly, and pose a long-term danger to the condition of the soil. For many farmers, quarantine is the only available measure, which generally involves killing infected plants, along with uninfected plants within a 30 m/100 ft radius, with a mixture of diesel and herbicide.

  THE COFFEE BORER BEETLE

  Hypothenemus hampei, also known as the coffee weevil or gorgojo del café is coffee’s single greatest natural predator. Native to Western Africa, the adult mites grow to 1.5 mm/1/16 inch in length, and unlike the rest of the insect world, are undeterred by the presence of caffeine in the coffee fruit. The beasts bore into the fruit and build tiny egg chambers – which subsequently hatch larvae – inside the coffee seed. Females fly around colonizing additional plants and males lurk about ready to perform their part in the process, never even needing to leave the fruit. If left unchecked the activities of the beetle can devastate entire harvests, with some estimates claiming the total annual global losses to be in excess of £315 million/$500 million.