coffee!

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Keep in mind that I am not a professional, neither in coffee nor in medicine. Just really interested in coffee! So take the science part of this page with a grain of salt.

By the way, did you know people have been putting salt in coffee? To be fair, people have put a LOT of stuff into coffee, such as oil, butter, jam, cinnamon, matcha, pumpkin spices, so that's fun.

I've spent some time looking into this nice beverage's properties and had independently built up a bulk of notes on it, so I thought it might be a fun idea to make a page about it in here , building from that research. :)

On Caffeine

Caffeine is produced by many plants, about 60 types - one of which is coffee. Caffeine is a methylxantine alkaloid.

Coffee is produced by plants as a pesticide - but research has also shown that caffeine can improve bees' memory, helping them link the smell of the flower and its nectar, thus being beneficial for the plant's pollination! This is probably why some plants produce low doses of caffeine in the flowers.

Caffeine is absorbed through the gastrointestinal tract and reaches its peak concentration in the body around 30-60 minutes after ingestion.

Scientifically speaking (☝️), Caffeine affects the body in 3 ways:

  1. It blocks the Adenosine receptors in our bodies. Normally, adenosine connects with those receptors, inducing a feeling of relaxation or drowsiness, and Caffeine prevents that from happening; it also stimulates the body to increase the production of Dopamine and Noradrenaline.
  2. Caffeine can also cause the release of Calcium inside of muscle cells, and it can prevent or slow its re-uptake. If consumed on very high doses (>500mg, which is a lot) this hyper-availability of calcium can temporarily increase the power of the muscles.
  3. Caffeine can inhibit Phosphodiesterases - stopping these enzymes' production can cause the body to burn more fat, on VERY high doses (the equivalent of many, many cups a day).

The feelings of goodness that we get are however not so much of improving our cognitive functions, but are an effect of alleviating withdrawal symptoms. It has been shown for caffeine to act as both an alleviating and a preventive factor for Alzheimer's and Parkinson's.

Caffeine can also have negative effects: mild anxiety, jitteriness, insomnia, reduced coordination. -- However, small consumption have been shown to be correlated with reduced symptoms of depression.

How much caffeine is considered healthy? It varies because people metabolyze caffeine differently, but for adults it's usually no more than 400mg/day, 200mg/day if pregnant/breastfeeding. Caffeine toxicity for humans is about 10g of caffeine in a single day. Which is, again, A Lot, many times more than you'd likely take during the course of a regular day.

Coffee's quantity of caffeine will vary depending on many factors: Arabica, for example, has half the amount of caffeine than Robusta; but the recipe and way it is brewed will have an impact on caffeine content as well. It ranges between 65mg to 300mg in a cup.

Roasting the Coffee Beans

  • Light roasts are better for specialty coffee because there is less bitterness and it lets out the specific flavour of the beans.

  • Dark roasts are more bitter as they are more roasted, but the acidity goes down.

  • It is not ideal to roast coffee in an oven -- but there are ways to do that either in a pan (stirring the beans the entire time) or in a shakeable holed pot you shake around, making the beans tumble around the donut-shaped metal thing.

There are about two "cracking" moments when roasting, it is where the beans "crack"; when they reach a certain level of roasting.

Grinding

There's a whole section I wanna make about grinding cause the way it influences brewing and the funny and clever ways people have come up with solutions to that interests me too, but I haven't yet have had the time to

Technical Terms Coffee Nerds Use and Trends I've Seen

  • Puck prepping: That intricate ritual where you prepare the coffee grounds into the portafilter before making an espresso in an espresso-making machine. It can involve many things such as the specifics of the grinding, poking and moving around the coffee grounds with needles to make them more even (WDT?), pressing them with a tamper to make water struggle more inside the portafilter, in order to extract more flavour

  • Espresso: a coffee which is denser, and usually less in quantity than filtered coffee. Has crema (the lighter part on top). The standard in any italian bar or coffee shop. (If you just ask for a coffee, this is what you get). To achieve it, coffee needs to be extracted quickly and with high pressure, usually with an espresso machine, but there are some funky alternative ways to achieve that, more on that below

  • Filtered Coffee: A 'family' of coffee brewing methods whose preparation require you to put coffee grounds into some kind of (usually paper, but there are funky trends such as ones made of ceramic, apparently??) filter, and to pour hot water on top. Gravity does the work: water will go through the coffee and then through the filter, filling your cup with coffee. V60 and Chemex are considered filtered. More "watery" but you usually you can make more of it.

Methods of Brewing

Moka Pot

As an italian, I am contractually obligated to put this one first. Objectively the best way to brew coffee forever ever trust me 100%.
Makes a coffee which has been deemed very similar to espresso; works best with dark-roasted and robust qualities and coarser grounds of coffee. I am not kidding when I say I'm 98% sure at least 2/3 of italians have at LEAST one at home, or wherever they live.
Very easy to use, fun to prepare, doesn't require paper filters, just some fire, and a good cleaning every now and then. As picture, have a gigantic Moka I came across, in a Bialetti shop.

French Press

It is a practical way to brew coffee which involves pouring water inside this mechanism, letting it brew for around 3/4 minutes, then pushing down the grounds of the coffee and then pouring it to drink. It uses a metal filter. Usually there is a bit of coffee grounds still in the cup when poured. Very popular in English-speaking countries, I hear.

Chemex

It is a one-piece glass brewer, with a "handle" of sorts made of wood, and a little leather tie. Coffee is brewed through larger and thicker filters, using more paper; the thick part rests on the channel which lets the air out, in order not to clug it.

Arabic Coffee

Arabic coffee is a family of coffees brewn either in dallahs (in pic) or, nowadays, just on stovetops, and then served for guests. When served cerimonially, it is courtesy to accept at least one cup from the host. Coffee grounds are boiled in the item of choice and then served very little at a time in small cups. Spices such as cardamom or cloves or saffron may be added in the boiling phase to taste, and it can be served with sweet things on the side.

Turkish/Greek Coffee

I am NOT getting into the etymology debate here, but; this coffee is brewed with very very fine coffee, almost flour-texture, and spices such as cardamomo can be added in. The coffee is poured directly in the water you drink. You drink the whole thing. It is best not to let the coffee+water boil, but arrive just before it boils, then raise it above the flame. I've seen people do it by running the cezve/briki (the metal pot which contains the water+coffee mixure) upon very hot sand, in order to make the liquid boil and form a foam.

Aeropress

This plastic contraption allows you to brew coffee with pressure: you put a paper filter there, fill the tube up with water, and literally press the thing down, like a huge air syringe, and the air pressure you create pushes the water through the coffee with force, brewing it quickly. It's portable and fast, I'll give it that.

Cuccumella/Napoletana

This one is funny. Looks and works almost like a Moka but you flip it meanwhile. Hey, instead of me telling you boringly how to do it, listen to how Sophia Loren describes The Perfect Coffee in "Questi Fantasmi" (written:1945, movie:1962) dir. Renato Castellani. Yeah it's in italian but you'll understand. Ignore the other guy proposing to her, that's not about him

Bonus: Instant coffee DISASTER at my university

The department's coffee machine broke and only delivered dirty water for an entire morning.

Here is the tragic graveyard of the cups of the unwise students who brewed nonetheless, unaware of the trap which poorly-calibrated electronics had laid down for them.

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