After Water, the next most refreshment dink we consume is tea. This is obvious because Tea ingredients are actually available anywhere on the planet. Yet that’s not really the case for coffee. If I make a top 3 of the most consumed refreshment drinks by humans I have can put them precisely in this order.
- Number 1 = WATER
- Number 2 = TEA
- Number 3 = COFFEE
While tea can be harvested from plants which can grow anywhere on Earth, coffee typically grows in forests, in countries like Brazil or Guatemala, where they have high summer temperatures and plenty of rainfall. Like the tea plant, the coffee bush has evolved chemical defenses to protect itself against being eaten by animals and insects, in the form of powerful alkaloids like caffeine, which can disrupt the metabolism of an organism. Caffeine’s bitterness is a biological signal from our mouth warning us that we are about to drink something that may be toxic – but, in the case of caffeine, we ignore it; why is that?
It’s probably because we’ve grown to like the effect of caffeine on our bodies, as well as other naturally derived alkaloids, like nicotine, morphine and cocaine. But, of all these psychoactive substances, caffeine is the most widely consumed. It stimulates the nervous system, relieving us of drowsiness, making us more alert. It is also a diuretic, which means it increases the production of urine. The upshot is that after you drink a strong coffee you often need the toilet. At high doses, caffeine can cause insomnia and anxiousness. Caffeine, like alcohol, goes straight into our bloodstream, so its effects are immediately noticeable; and, as with the other alkaloids, it’s addictive.
Once you start drinking it regularly, it can be incredibly hard to stop; the withdrawal symptoms can be severe, giving you headaches, making you tired, crabby, sluggish.
HOW COFFEE IS MADE?
The coffee we drink is ground from beans, which are the seeds of the coffee bush. They contain a lot of carbohydrates, in the form of sugars, which give the seed the energy it needs to produce new shoots. The bean also contains proteins, which provide the core molecular machinery for the plant, and instruct the seed through the reproductive process – the growth of a new coffee plant. Once the beans ripen, they’re harvested, fermented, removed from the pulp and dried. At this point, they’re hard, pale, green beans. The next step is to roast them; this is where the huge array of flavour in coffee is developed.
THE MOST COMMONLY CONSUMED TYPES OF COFFEE.
TURKISH COFFEE
The earliest known methods for grinding and brewing coffee are from the 15th century, in Yemen. Arab communities there ground the coffee with a simple pestle and mortar, added it to water and then boiled the mixture. his is still a popular way of making coffee in the Middle East; it’s often called Turkish coffee.
Making coffee this way gives you a very strong, dark brew; the liquid contains not just the taste compounds of the coffee, but also the grounds themselves, which affects the mouth-feel of the drink, giving it a velvety texture. But this smoothness can turn gritty as you get towards the end of the cup, where the bigger solids form a thick sediment on the bottom.
Turkish coffee is also quite bitter; brewing the grounds at boiling point allows a lot of the highly bitter-tasting molecules, like caffeine, to dissolve into the water in large quantities. Generally, people mix a fair amount of sugar into their coffee to offset this, resulting in a bittersweet drink with a high caffeine content. Just what the doctor ordered, if you want to be hopped up on a strong wallop of flavour, combined with the one-two punch of a lot of sugar and caffeine, then feel free to do so.
But, as satisfying as this can be, brewing coffee this way does eliminate a lot of the fruity flavours from the bean’ s fermentation, and the nutty and chocolaty flavours you develop through the roasting. Thus we discover one of the biggest problems with coffee – it often smells better than it actually tastes. Why? Because so many of the aromas that should have been released inside your mouth have already been released into the air while the coffee was brewing, leaving behind just the bitterness and acidity, with very few of the aromatics.
FILTER COFFEE
As an alternative to Turkish Coffee in order o keep from losing so much of the aroma during the brewing process, it’s best to brew at lower temperatures. This also limits the bitterness, and gives you coffee with a lower caffeine content. While the velvety texture of Turkish coffee can be quite pleasant, those last sips of grit aren’t great. As such, separating the coffee grounds from the liquid became a major objective in the brewing process – welcome, the coffee filter.
Making coffee by filtering it through a fine mesh or a filter paper allows the coffee to be brewed as the hot water comes in contact with the fine grains, but then the liquid drips through the filter, and into another collecting vessel, leaving the grains behind. The speed of the process is determined by how hard it is for the water to be pulled through the grounds. If there are too many grounds, or the powder is too fine, then the water takes a long time to drip through, thus dropping in temperature, which makes it impossible for the liquid to extract all of the molecules that could give the drink flavour. Likewise, brewing the coffee with too much water, or too-coarse grains, will give you a weak cup, with little body and too much acidity, because the water won’t be in contact with the grains long enough. But if you do it right, filtering will give a warm pot of clear, golden, grain-free coffee. There won’t be a crema, though.
For a lot of people, the perfect cup of coffee has a crema floating on top of the liquid – a foam created by the carbon dioxide gas that’s produced during the roasting process, then released from the ground beans while the coffee’ s brewing. When you use a coffee filter, all the carbon dioxide is released during the filtering.
No matter, though; over the last 400 years, many other brewing methods have been invented that preserve the crema, including the cafetiere, the Moka and, of course, the espresso machine.
CAFETIERE COFFEE
Along with producing a crema, the cafetiere is generally faster than using a filter because the coffee grounds are first mixed with the water at about 100°C, and as the coffee brews – usually for a few minutes (further brewing releases a diminishing return of flavour, and increases bitterness) – the temperature decreases to about 70°C. So, the flavour molecules are, at first, extracted quite rapidly, as the surface of the coffee grains are exposed to the hot water, but that declines as the temperature goes down, and it becomes increasingly difficult for the water to access the interior of the partides. This is when the carbon dioxide is released from the grains, and escapes to the surface of the pot, trapping the liquid and forming the crema.
When the coffee’s done brewing, you just have to plunge the cafetiere’ s filter to stop the brewing and trap the coffee grounds. . If you pour the coffee immediately, you’II have a balanced, hot cup with that pleasing crema on top. To make stronger coffee without increasing its bitterness, you can use either lots of coarse grains or fewer fine grains, the problem with the latter being that they can escape through the plunge filter and make their way into your cup, and the problem with the former being that you won’t be able to extract as much flavour from the grains.
ESPRESSO COFFEE
The easiest and fastest way to make a coffee that is to let the espresso machine do it for you in less than a 1 minute. The espresso machine, so named because it can make coffee in 30 seconds, heats water to between 88°C and 92°C, and then puts it under intense pressure (about 9 times atmospheric pressure), before pushing it through the coffee grounds. The high pressure extracts the maximum amount of flavour and, because the system doesn’t rely on steam, it doesn’t overdo the bitterness and astringency. The speed of the system is important: it means there is very little time for the volatiles from the coffee to escape into the air. So you end up with a full-bodied coffee, with a great balance of nutty, earthy, savory flavours, both fruity and acidic, with a wine-like astringency. Because the mechanisms of an espresso machine are so controlled, it produces great coffee every time, and it’s incredibly fast. This is why it’s used in most commercial coffee shops, and the number of drinks you can make with it seems to have no end. Served on its own, it’s called an espresso. If you add hot water to it, you’ve got an Americano; equal amounts of hot milk and foamed milk make it a flat white; foamed milk on its own makes a cappuccino; and so on. As with tea, milk changes the flavour profile of coffee quite radically, smoothing the astringency, but also flattening the flavour profile and replacing it with a maltier, creamier flavour.
MOKA COFFEE
It can happen that the coffee the espresso machine is giving you might not really entertain your taste as you might expect, so there must be an alternative. . Such alternative can be the coffee made in a Moka pot. But then comes the question which one is better? One way around this dilemma is to try a Moka coffee pot.. In this device, the water is kept separate from the coffee grounds in a sealed compartment. When it’s heated to a boil, the water produces hot steam, which increases the pressure in the pot, eventually reaching about one and a half times the atmospheric pressure, and pushing the hot water through the coffee grains, and into an upper compartment once its brewed. Using the Moka extracts a lot more flavour than the cafetiere or a coffee filter, and it makes a strong cup. The downside of the Moka, though, is that, as the water level in the boiling chamber decreases, incredibly hot steam mixes with the water, and as that steam passes through the coffee grounds, its high temperature extracts a lot of bitterness, often giving the coffee a burnt edge. The espresso machine refines the principles of the Moka into the most reliable – and some say the best-tasting – coffee that can be made.
AEROPLANE COFFEE
Aeroplanes use smaller versions of espresso machines to serve first-class passengers, but the coffee served to everyone else made with a filter. Due to the lower air pressure on an aircraft, the boiling point of water is around 92°C – which, incidentally, is perfect for coffee. That being said, coffee that’s been kept warm for too long a period of time between brewing and drinking – as might happen on a plane, or in your office coffee machine – will lose a lot of its aromatic flavour, leaving you with just bitterness and astringency.
And that’s not the only thing keeping you from enjoying that sort-of-hot aeroplane coffee. Studies have shown that our sensitivity to the 5 basic tastes – sweet, sour, salty, bitter and unmami – is affected by aeroplane noise, as well as our sense of smell. Because of this, it’s impossible to taste the coffee you’re drinking with the same nuance you might on the ground. This confirms my experience of flying; I generally don’t enjoy coffee on planes as much as I think I’m going to.
So when you are on board of plane you might wonder which drink is better – coffee or tea? Certainly, each one suits different moods and moments in life. But there are times, such as when you’re on a plane in economy class, when you need to recognize that even if tea suits your mood, the chances of getting a good cup are so slim, you should just say NO. I say this really as a note to myself. To me the best refreshment drink on board of a plane is water. Or as I sometimes do I buy a cold beer before on-boarding, or eventually a bottle of cold sparkling water.
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