Is coffee a diuretic? Perhaps it seems strange to start a review of a fantastic little cafe with such a question, but all will become clear. Or will it?
Alchemist coffee in Singapore’s Raffles Quay district was a serendipitous find. A small outlet, almost a deep hole in the wall (with bench seating) in the middle of a walkway through a building. The shady walkway is the sort of space in Singapore that you duck into in order to avoid the glare of the Sun and take brief advantage of the air-conditioning in the otherwise powerful heat. And yet, escaping into this passageway, I was immediately struck by the aroma of the coffee indicating that a speciality coffee store was nearby. On noticing the queue of customers coming out of the door, this was definitely marked as a cafe to return to at a quieter time.
Returning a bit later we noticed that, at these quieter times, it was possible to have a pour over of some locally roasted coffee. I tried the Kenyan with currant and hawthorn tasting notes as, although I forage for hawthorn in the autumn in the UK in order to make brown sauces, it is unusual to find it as a tasting note there. We watched as great care was taken to prepare the pour over (Kalita wave) and the barista took a small glass of the coffee to try before serving it to me in the pre-warmed cup. Which marked another point of interest in this small cafe, although you may expect such a small outlet to serve only take-away coffee, even for customers who want to sit on the two bench seats that line the sides of the shop, the coffee is in fact served in a proper cup, an excellent point to see. Alchemist is actually three cafes, the one that I tried in Raffles Quay and two others, with the larger branch at the International Plaza being where they also roast the coffee.
A rack of items for sale featured filters for the Kalita wave as well as bags of the coffee roasted by Alchemist. And while initially this prompted thoughts of the differences in fluid dynamics between the Kalita wave (flat bottomed, ridged filters) and the Hario V60 (conical, flat walled filters), the reflections of the lights above in the coffee below turned this thought train in quite a different direction.
Like the cafe Alchemist, in some senses the discovery of the element phosphorus was an accidental affair. Accidental in the sense that Hennig Brand (~1630-92) who discovered it, was looking for something quite different: gold. Brand was an alchemist in the original sense of the word and, for whatever reason, thought that he may find a source of production of gold in urine.
Who knows how much urine he had to store and had to boil before he noticed its glow in the dark properties that were caused by the element phosphorus? Brand’s discovery occurred after the introduction of coffee into European coffee house culture, could its reputation as a diuretic have helped in the discovery of phosphorus? While entirely speculative, what is clear is that the name ‘phosphorus’ comes from the Greek and means the bringer of light (phos). The element phosphorus is used in many fertilisers as well as in matches.
The name of the element “phosphorus” conjures up terms such as phosphorescence, fluorescence and luminescence. While we sometimes use the term phosphorescence to describe substances that glow in the dark. This is because phosphorescent materials absorb higher energy light (such as UV) and then re-emit it some time later (which can even be hours after being ‘excited’ by the higher energy light such as sunlight). Fluorescent materials on the other hand also emit lower energy light as a result of the substance absorbing higher energy light, but they do so fairly immediately. Strictly speaking however the ‘glow in the dark’ properties of phosphorus do not come from phosphorescence but chemiluminescence: it glows in the dark because it emits light as a result of a chemical reaction, in this case oxidation.
The lights on the ceiling in the Alchemist were of the fluorescent type and so we may think that our connections with Hennig Brand and the alchemists of old are limited to the speculations on the name. But we’d miss one detail were we to do so. Fluorescent lights can use a voltage to excite mercury vapour to emit light in the (high energy) ultra violet region. This UV then interacts with a coating on the inside of the glass tube of the light which then fluoresces to give the light that we see reflected on our coffee. The substance that provides the coating? What else but phosphorus.
From Germany to Singapore, alchemy to Alchemist, and even urine to coffee, the reflections, metaphorical and actual, between the chemists of old and the baristas of now, consist of more than just the name.
Alchemist (Singapore) is in the Hong Leong building (Raffles Quay that was tried here) as well as the International Plaza (where they roast the coffee) and the Khong Guan building.
