Caffeine on the Brain

It is estimated that more than two billion cups of coffee worldwide are drank everyday. Add the delightfully restorative drink ‘tea’ into the equation and no other mood-altering stimulant is consumed on such a potentially global jitter-inducing scale.

So, what exactly is caffeine?

Firstly, caffeine comes from an organic family of nitrogenous compounds called xanthine alkaloids that, when consumed, give rise to marked physiological – and psychoactive – effects on the human body. Other sources known to contain this powerful compound include the Gurana berry, Cocao bean, Kola nut, Yaupon Holly tree, and South American Yerba mate, amongst many others (so far, up to 60 plants are known to contain the compound caffeine).

But for the purposes of this post, I trust that you will forgive me if we stick to coffee.

The 'Father' of Caffeine? Friedlieb Ferdinand Runge

In 1820, caffeine was first isolated from coffee by the German chemist Friedlieb Ferdinand Runge, apparently at the behest of Johan Wolfgang von Goethe. The following year, the French chemist Pierre Joseph Pelletier, coined the word ‘cafeine’ after the French derivation for the word coffee; café. However, it was not until the end of the 19th century that its complete chemical structure was discovered by Hermann Ermil Fischer, who was the first person to achieve its total synthesis. Fishcher was later awarded the Nobel Prize in 1902 for his work in this field of organic chemistry.

Pure Caffeine Powder

Caffeine, or to use its laboratory name – 1,3,7-trimethylxanthine – manifests itself in its purist from as a white crystalline solid. Yet to the human brain, it is one of the most effective ‘cuckoo’ compounds in the chemical world.

Here’s why…

Throughout the day, the neurotransmitter adenosine is naturally created in the brain and builds up to a level that eventually helps to bring about the onset of that deep, regenerative state we know as sleep. It binds to the receptors resulting in a feeling of drowsiness by slowing down nerve cell activity whilst the blood cells dilate to allow more oxygen to the brain.

Caffeine: The primary antagonist of adenosine receptors in the brain

Now, as far as your average nerve cell is concerned, caffeine, with its chemical structure – C8H10N4O2 – looks suspiciously like adenosine – C10H13N5O4 – thereby allowing this chemical ‘master of disguise’ to bind to the adenosine receptors. But the psychoactive result is the exact opposite. Instead of inducing a feeling of drowsiness, the chemical composition of caffeine encourages the nerve impulses to speed up.

This build up of chemical mimicry prevents the real adenosine from binding to its own receptors. Consequently, the brain is kick-started into a state of arousal and becomes more alert. The stimulating effects of caffeine on the central nervous system also dramatically increases the amount of the ‘happy’ neurotransmitter dopamine to be produced. These heightened levels are coupled with feelings of well-being and improved mood. It is in fact the psychoactive effect of dopamine that makes caffeine so addictive.

Now things start to get really interesting.

As the brain experiences a speeding up of nerve cell activity caused by the neuro-pathways firing on all cylinders, the body goes into ‘fight or flight’ mode. It is at this juncture that the pituitary gland steps into the proceedings, and sensing an emergency, sends a signal to the adrenal glands to produce more of the hormone epinephrine, also known as adrenaline.

We all know what happens next.

With the body now in a state of heightened alert, the all-too-familiar symptoms of increased heart rate; raised blood pressure; sweaty palms; a ‘spike’ in levels of blood sugar produced by the liver to provide extra energy; dilated pupils; suppressed appetite; and a tensing of the muscles; are just some of the side-effects of this biological ‘code red’. Once the perceived ’emergency’ is over, the body’s adrenaline and dopamine levels start to return back to normal, coupled with a slowing of nerve cell activity as the adenosine begins to bind to the receptors once again. It takes approximately ten hours for caffeine to fully leave the system.

Caffeinated Spiderweb

Like anything consumed in excess, too much caffeine can prove fatal. Just 10g is considered a lethal dose. Fortunately, an average espresso contains a mere 100-150mg so seriously herculean quantities of the stuff would have to be consumed in a single sitting to bring on death.

This cannot be said of spiders…

In the final analysis, we all have to make our own personal judgement about the pros and cons of caffeine consumption, once in full possession of the facts.

But before you reach for the decaf (which still contains caffeine – just a reduced amount), stop and spare a moment to consider this mysterious but potent ‘cuckoo’ of the chemical world, and its powerful effects.

For good or for bad, it is without equivocation that caffeine on the brain changes the body’s chemistry.

In more ways than one.

The Science (and Art) of Roasting Coffee

It is said that coffee roasting is ‘part science, part art, and part magic.’ This indeed is true. In fact, the science involved in the process of roasting coffee beans is nothing short of astonishing.

Witnessing the process for the very first time, this is my personal account of what happens. Now, I do have a confession to make. In no way do I claim to be knowledgeable or experienced in this fascinating field (far from it) but the following description is a humble attempt to record my observations and what I have learned so far. So here goes…

“It takes 400 man hours for every pound of unroasted beans to reach this point. Now is not the time to get it wrong”, said artisan roaster, Ian, as he excitedly fires up the trusty 14lb (in old money) capacity Uno. With a ‘pop’ and a ‘whoosh’, the blue flame from its DNA-like helical gas burner breathes into life. Allowing time for the post-war roasting machine to warm up, he methodically inspects the six kilo batch of hard, tasteless Ethiopian Yirgacheffe (produced in the lush, deep soils of the high-rolling mountains of the Sidamo region, southern Ethiopia) for any ‘offenders’ that do not make the grade and could potentially spoil the entire process.

To the nose, the beans give off a delicate profusion of freshly mown hay or the smell of the earth just when the first raindrops fall on the dry, sun-kissed ground in summer. Only when the roaster is completely satisfied with the overall consistency in quality and size, does the Uno’s vintage belt-driven motor hum into action. The beans are then carefully poured into its horizontal-axis chamber. To a soft percussive rhythm, the lightly green and blue-hued beans become a blur as they brush the insides of the rotating drum.

As each second passes, the unhurried alchemy of extracting the delightful flavour from the coffee gradually reveals itself.

In a seeming state of perpetual free fall, the – as yet – unroasted beans begin to absorb the heat from the Uno’s centrifugal fire. Five-or-so expectant minutes pass. Nothing much of note happens to the untrained eye during this preliminary ‘drying off’ phase. And then, the first wisp of a feint smoky aroma, like the smell of toast, begins to emanate; a sensory prologue to the action that is to follow.

At this point the core temperature inside the coffee bean has broken through the threshold of 150-160 degrees centigrade, and is steadily climbing. At the molecular level, this magical moment is coupled with an explosion of cellular activity as the bean’s very chemical composition starts to dramatically change in a series of volatile runaway reactions. In physical terms, this metamorphosis is the transition from an endothermic (to take in heat energy) state to becoming exothermic (to give out heat energy).

It is shortly after this stage when the first ‘crack’ – not dissimilar to the sound of the popping or splitting of popcorn – of the coffee bean occurs and the effects of the increased energy inside the bean becomes visible. By now, they are starting to release their hidden aromatic oils that have been conspicuously concealed so well since their early days of infancy as an unripened green berry on the bush. In the following minutes, the temperature rises further to approximately 220 degrees. The pressure increases too; creating the optimum conditions for the necessary exogenous chemical reactions to take place.

Cascading inside the Uno’s spinning drum, the beans take on a yellow-orange colour as they start to give up their locked-in moisture. Water vapour and carbon dioxide is released in extraordinary quantities through the ‘fissure’ which  runs through the centre line of the bean. This leads to a rapid expansion in volume (up to twice the bean’s original size), accompanied by a marked loss in weight and density. In the parlance of the chemistry class, it is known as the Maillard Reaction. From a personal perspective, it is as though the beans are bursting back into life after a suspended period of deep hibernation.

The temperature still rising, further complex chemical reactions occur between the amino acids, carbohydrate and sucrose compounds (more than 800 hundred have been identified so far). By now, the beans have turned to a light brown colour signaling the ‘carimalisation’ of the natural oils and sugars that give the coffee bean its distinctive colour and rich flavour.

The skill – or ‘art’ to be more exact – of the speciality roaster is the intuitive use of his or her senses. Without a temperature gauge or timer in sight, the roaster falls into a spell of intense concentration as the final critical moments approach. Like a Michelin-starred chef or master wine blender, he is using all his senses to bring out and enhance the best characteristics that the Yirgacheffe has to offer. Meanwhile, the beans take on a dark chestnut colour as the premises of J. Atkinson & Co. fill with their delicious, almost floral, nutty aroma.

Asked if he is ever afraid of the beans catching fire, Ian enigmatically responds, “every roaster is christened with his first fire at some stage, I decided to get mine in early”.

It only takes a mesmerising 12 minutes from start to finish. With a final flourish of the roaster’s hand to bring the Uno’s rhythmic mechanical overture to a close; the drum comes to a stop, the helix flame is extinguished and the roasted Ethiopian Yirgacheffe beans spill out into the perforated cooling tray below. Lightly coated with their natural coffee-flavoured oils, they glisten in the low mid-afternoon sun, as they are patiently stirred to bring their temperature back down to an ambient level.

Stages of Roast

Depending on the specific roast desired (low, medium, high; full roast, double roast), the bean can go through a further two or three ‘cracks’ until the roaster decides to terminate the process. Done with expert split-second timing, this is to ensure that the balance of flavour, complexity of taste and acidity levels all add up to the holy grail of the experienced Roastmaster: Perfection.

Coffee roasting is a centuries-old craft. In today’s age of impressive scientific discovery, we still do not fully understand the massive thermodynamic changes that roasting brings about inside the bean. One thing is for sure however, I now understand why its is affectionately referred to as an ‘art’.

And what about the ‘magic’ I hear you ask?

Well, all I can say is that you only have to taste the sublime Ethiopian Yirgacheffe coffee for yourself to discover the answer.

A Cup Above the Rest

In many respects, this journey did not start in London. It began in Lancaster. And where better than to embark on a coffee-inspired bike ride to Ethiopia other than the historic premises of master tea blenders and coffee roasters, J. Atkinson & Co.?

Established in 1837 as the Grasshopper Tea Warehouse, J. Atkinson & Co. has traded from its China Street premises since 1901 and is undoubtedly the jewel in the crown of the city’s illustrious heritage. Walk into the welcoming premises of this family-run business and the first thing that greets you is the warm, enticing aroma of the artisan roasted coffee bean.

Pause for a moment, and the delicate fragrance of expertly blended tea complements the sensory experience.

Inside, every aspect has been lovingly restored back to its former glory. In one corner stands the ‘Uno’, the stalwart coffee roasting machine which dates back to 1945 and continues to fill the street outside with its delicious aroma – as it has done for generations. The mouth-watering menu of more 80 different varieties of coffee and blends spanning the globe, each with a unique provinence of their own, are all carefully ground to your own requirements; if that is what you prefer. Similarly, bell jars of blended tea from the subtle to the exotic adorn the shelves; just waiting to release their heavenly infusion. It is clear to see that trade is brisk but the pace behind the old vintage counter is measured, almost reverential, in respect of a special kind of alchemy that takes place on these premises daily.

Prior to being waved off by artisan roaster, Ian, on a bitingly cold December afternoon with my gift of unroasted Ethiopian Yirgacheffe beans concealed in the bike frame, I was privileged to be given the opportunity to familiarise myself with the time-honoured art of the Roaster and Barista. A debt of gratitude is owed to proprietors Ian and Sue Steel for their generosity of knowledge and who effortlessly accommodated my endless questions on that busy, but special day.

A further highlight was the chance to spend some time with Barista-par-excellence, Caspar, who has taken out a Gap Year to run the contemporary Music Room Cafe. Like an expert craftsman or artist who’s smooth and precise movements belie years’ of training, creativity and dedication, he introduced me to the sublime profession of Latte Art. Respect.

A truly inspiring, humbling and unforgettable experience.

In an age of rampant globalisation, outstanding establishments like J.Atkinson & Co. – who play their play their part in the wider global community by ethically sourcing the very highest quality of tea and coffee – are hard to come by.

In a word? Passion.

In the Beginning…

It is told that the rejuvenating and stimulating effects of the coffee bean plant were first discovered in Ethiopia by an Abyssinian goat herder, named Kaldi, back in the 9th century.

One day, while Kaldi was tending to his goats, he grew tired and decided to take a quick nap. He later awoke to find his goats dancing gleefully around him.

Kaldi decided to investigate what was causing his goats to behave so energetically. Following them, he was led to a certain bush that produced an abundance of bright red, yellow and green berries.

After tasting a small handful, Kaldi began to experience a similar elation that he had observed in his goats earlier that day. He took them back to his village and presented the berries to the village elder in a state of excitement. The elder, skeptical of Kaldi’s discovery, threw them into the fire. Minutes later, a rich enticing aroma filled the air. The roasted beans were quickly raked from the embers of the fire, ground up, and placed into a bowl of steaming hot water.

And so legend has it, that high up in the in the Ethiopian province of Kaffa many centuries ago, the world’s first cup of coffee was made. The rest, as they say, is history.