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Seeing the unseen at Scarlett, Angel

Coffee Angel, Scarlett, roasters, coffee in Islington
Coffee at Scarlett, Angel

Although first alerted to Scarlett coffee in Angel by Double Skinny Macchiato last summer, we managed to visit during the one week of their summer holiday (and so we revisited Katsute100 around the corner instead). Nonetheless, it remained on the list and a few weeks ago we turned up for a mid-afternoon coffee at this inconspicuous looking venue on a side street just around the corner from Angel tube.

The roaster at the back of the cafe forms an immediate impression. With the large, communal table at the front of the cafe, backed by stairs leading up to the roaster, this is a place where coffee is taken seriously. The counter (on the left as you enter) offered a range of cakes and edibles but having recently come from lunch in Chapel Market, we passed on this on this occasion. Above the counter there were about 5 lights hanging down forming what looked like a giant Newton’s Cradle. Just too high for me to reach unfortunately.

I enjoyed my long black as I started to take in the surroundings of this cafe. Various people and regulars came and went, suggesting that this is a friendly local haunt for many. Noticing the number of different roasted coffee beans for retail, it was clear that this is a venue that you could return to for a different coffee experience each time. Each time exploring an aspect of the flavour of the coffee and building on the experience of coffee tasting that you have enjoyed before. It is definitely on the list for a repeat visit.

Interior Scarlett
One of the light fittings at Scarlett in Angel. Cube outlines drawn on paper can form an optical illusion where you can’t work out if the cube is coming out at you or going into the paper.

Above our heads, the lights were framed by the outline of a cube. Fantastic for optical illusions, these cubes offer us an opportunity to think about how we perceive depth and direction; how our eyes work and perhaps, more fundamentally, what it even means to see an object (as with Berkeley’s “New Theory of Vision”). Then, while looking through the menu, it became clear that here too there was an optical illusion of sorts. For the price list was not written on the board so much as cut out of it (see the photo below). The price you could read off the menu was, in some sense, precisely the information that was not actually on the board. Our brain makes patterns of that which we don’t see and, together with our assumptions about what should be there, we form an idea of the price we have to pay.

It is a similar thing with many algorithms in use around us now. Such tools can be immensely helpful, offering us suggestions for coffees we may like to try (based on our buying habit) or routes that we may like to take to get us to our destination. And yet, are there problems hidden in the assumptions that some of these algorithms make? What information are we getting based on elements in the programme that we do not see?

In her excellent book “Weapons of Math Destruction”, Cathy O’Neil explores some of the more dangerous ways that our biases and assumptions (particularly those that we don’t see in ourselves) can impact the results of algorithms that have been written to optimise processes from the sorting of job applications to determining the length of time a given convicted criminal will serve for an offence. In an example relevant for cafes, O’Neil related an example of how Starbucks had used an algorithm to determine which baristas and managers should work which hours, including who should close the shop at night and who should open it in the morning.

Scarlett menu
The menu at Scarlett. Apart from the filter coffee, the prices and information for each coffee is revealed by what is absent from the board rather than what is printed onto it.

The algorithm was programmed to calculate the most efficient use of the cafe’s time and money, specifically prioritising the profit that the company made. One measure of this was “revenue per employee hour”. This had the consequence that staff members were frequently in a position where they were told that they had to do both the (late night) closing and (early morning) opening of the shop and were given very few days notice of this expectation. Clearly this impacted the lives of their staff and affected their ability to arrange child care, support themselves through further education and other consequences. Eventually Starbucks was forced to amend this algorithm but change comes hard: how do you ask a computer to measure “fairness” to an employee (a subjective term) when you can use revenue per employee hour which is measurable, quantifiable and therefore ‘accurate’?

Perhaps you think that the link back to Scarlett here is obvious: That if you choose to drink your coffee in friendly neighbourhood cafes where cafe owners and baristas work to patterns formed by encounter rather than algorithm it would be better than a place which is run assuming all workers are cogs in a profit machine? Perhaps. But the link back to Scarlett in my mind is not that at all.

If you look at the front of Scarlett, or its webpage, and assume that the pink bird is a funny looking flamingo, you may make a series of assumptions about what you think the cafe will be like and why the owners have a bird on their front door. If you found out that the bird was actually a Scarlet Ibis and associated with the coffee growing regions of South America, your ideas about the cafe and the owners may be different. For a general customer, looking for somewhere to enjoy a great coffee, perhaps these assumptions and ideas do not matter so much. But if we are ever in a position to feed our assumptions into an algorithm, these hidden (to our own conscious) assumptions could matter a great deal.

Scarlett is at 30 Duncan Street, N1 8BW

“Weapons of Math Destruction – how big data increases inequality and threatens democracy” by Cathy O’Neil, Penguin Books, 2016

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On dew, greenhouses & IR thermometers: Coffee & Science at Amoret

starting with a coffee
Always good to start with a coffee. The evening started with two coffees (from Ethiopia and El Salvador). What will be the effects of climate change on the coffee industry?

January 2020 was the 6th warmest on record in the UK, with a mean temperature 2C higher than the 1981-2010 average. Early in February it was announced that Antartica had recorded the highest temperature ever recorded there of 18.3C, beating the previous record of 17.5C in March 2015. The atmospheric concentration of CO2 in January 2020 was measured to be 413 ppm following the trend that has seen the atmospheric CO2 concentration increase more than 10% from just the year 2000. That the polar regions would warm faster than other parts of the planet had long been a prediction of global warming based on increased CO2 emissions. Nonetheless, to see the figures reported quite so starkly was startling.

Each month brings new headlines and more concerns about whether we are responding fast enough to limit global warming to 1.5 or 2C. And yet, the greenhouse effect was proposed back in 1824; the idea that carbon dioxide (and water vapour) were greenhouse gases suggested during the 1850s (1,2) and it was back in 1895 that Arrhenius predicted that doubling the atmospheric levels of CO2 (relative to 1890s levels) would result in a global temperature increase of 5-8C.

So given that it is such an established theory, why are we still arguing about it? And, more importantly perhaps, what has this to do with coffee?

It is, in many ways, an ideal connection for the theme for one of the Coffee & Science evenings that we’ve been holding at Amoret Coffee in Notting Hill. And so it was that a group of us got together over coffee to discuss the greenhouse effect and its links to coffee.

coffee bowl pour over
The first connections can be seen with the condensation. How does dew form, and why does it suggest that space is cold?

The first coffee-greenhouse connection is in the condensation. When you make a pour over, or even if you pour your coffee into a cold mug, you will notice the condensation forming on the colder glass (or ceramic) surfaces as the steam evaporates. We know that the droplets form because the temperature of the surface is below that at which water vapour will re-condense into liquid. Technically, this temperature is known as the dew point. And it is partly to dew that we owe our understanding of the greenhouse effect.

Back in 1814, William Charles Wells made a series of detailed observations about how, where and when dew formed. He was able to show that more dew formed on clear (or not terribly cloudy) nights and on surfaces that were exposed to the sky; they were space facing. Which brings us to a second coffee connection: just as your coffee cup warms you by radiating its heat (in the infra red) to your hands, so all objects with heat radiate their energy out. Wells realised that this meant that space was cold because, just as a coffee cup if it is not being heated and not surrounded by reflecting material (think about the inside of a thermos flask) will radiate its heat and get cold* so the surfaces of the earth, if there is no energy coming in from space and no surfaces above them to reflect their heat back at them, will also get cold.

If space is cold, you can calculate what the temperature of the Earth should be if the energy it is losing is balanced by the energy it gains from the Sun and when you do this, it turns out that the mean temperature of the Earth should be -18C or about 30C lower than that observed**.

Earth from space, South America, coffee
One common home.
The Blue Marble, Credit, NASA: Image created by Reto Stockli with the help of Alan Nelson, under the leadership of Fritz Hasler

This leads to the idea that there is a natural greenhouse effect whereby gases in the Earth’s atmosphere form a layer which lets through a large amount of the energy from the Sun but lets a lot less energy escape back through it from the Earth (owing to the lower frequency of the radiation being emitted by the Earth compared with that coming in from the Sun). This ‘natural’ greenhouse effect results in a warming of the Earth to a delicate balance and to the temperatures that we experience on Earth***. Fairly clearly, if this delicate balance is disturbed by adding extra greenhouse gases to the atmosphere it will lead to a warming effect (as Arrhenius predicted back in 1895), the question is how much and how fast?

We were very fortunate to be joined for the evening by Dr Robin Lamboll of the Grantham Institute of Imperial College London. Robin explained the latest science and understanding of the effects of climate change and of adding increased CO2 into the atmosphere. Particularly highlighting how an increase in CO2 leads to an increase in water vapour (owing to the initial temperature increase produced by the CO2) which is itself a greenhouse gas, and so the warming effects of a small amount of CO2 can be amplified by this mechanism.

At this point the conversation diverged away from coffee, not just because Robin is a tea drinker (!) but we moved onto the effects of sulphur dioxide in the atmosphere, local vs global temperature effects and the science of Eunice Newton Foote. We discussed what we know, and what we are just starting to understand, such as how what happens in one part of the world may lead to consequences in other parts of the world (weather wise). We also got to a discussion of albedo and the reflection of heat by ice via playing with a couple of infra red thermometers that we had to hand and the different ways that human eyes and shrimp eyes detect colour. How is this connected to climate change and coffee? I’m afraid that there is a connection but the path to it is a little circuitous for a write up. It’s the sort of thing that pops up when you have a number of people of different backgrounds all contributing to the discussion. This is what, from my point of view, makes these evenings so interesting (and on a personal level induces such pre-event nerves): the fact that the conversation can go in so many directions, with such different contributions from the attendees, that each evening takes on a different character, with a different set of connections and a new set of things to think about. I hope that others feel the same way!

“An Essay on Dew”, Wells book of 1815 summarising his observations on dew. An excellent piece of observational science.

Our next Coffee & Science evening is scheduled for March 2020. Please do sign up to the events list or keep an eye on the Facebook events page to learn details as they are announced. Thanks again to Dr Robin Lamboll for coming along in January. I look forward to seeing both familiar faces and some new people in March.

Bean Thinking’s Evenings of Coffee & Science @ Amoret Coffee are held approximately every 2 months from 5.30 until about 8pm at Amoret Coffee in Notting Hill. More details can be found here.

*Two caveats here: firstly the coffee will also get cold through convection and conduction, the connection is illustrative rather than precise – though were you to put your coffee into a vacuum it would cool via radiative cooling only. Secondly, Wells himself never made the coffee connection but instead considered the latest physics theories about heat.

**In “Introduction to Atmospheric Physics”, David Andrews, (2000)

***For details about how we can know what the temperatures have been over such a time period and the effects of other cyclical temperature variations on the climate, it’s worth reading “The Ice Chronicles” P Mayewski & F White, (2002)

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Carbon Kopi

Carbon Kopi, coffee Hammersmith, coffee Fulham
Carbon Kopi, the sign in the window above giving a clue to the name without being a direct reference.

The name of this relatively new cafe in Hammersmith/Fulham was intriguing on several levels. Kopi means coffee in both Malay and Indonesian and, having recently travelled back from SE Asia, it was interesting to see what the link to this cafe may be. Then there was the pun in the name. The website explains it as representative of a desire to make a consistently good coffee, each being a carbon copy of the other. So both the name, and the cafe’s symbol have appeals for a coffee-science website. And so it was that we wandered down Fulham Palace Road to finally arrive at Carbon Kopi a few Saturdays ago.

The cafe occupies a corner building and is much larger than you may expect it to be. It is also friendly, airy and light with large windows giving plenty of illumination to the space. Allergen information was clearly labelled on the cakes and edibles (with extra information in a folder), which is always great to see.

Coffee was by Square Mile with guest roasters on batch brew and so we had a long black and oat milk hot chocolate which came served in huskee cups. Huskee cups are produced by re-using the husks otherwise discarded during the coffee milling stage. A re-usable cup that reduces waste certainly, but does it reduce the carbon footprint? An answer that depends on how many times you use it. Continuing the environmental theme, near the door, there was a separate bin for compostable cups. This was excellent to see because if compostable cups do not get to an industrial composting facility, they can take an absolute age to break down in a conventional compost heap.

Hat and huskee
Coffee in a huskee cup at Carbon Kopi. A protrusion on the saucer fits into the base of the huskee cup and stops it slipping across the saucer. Unlike graphite where the regular hexagons of carbon form layers that slip over each other to form a solid lubricant.

Across the road, the St Alban’s Church was made of brick. One row upon another, the set of bricks formed a layered structure. Where they met at corners or against the pavement they formed abrupt discontinuities, a sort of dislocation. Together with the small protrusion on the middle of the huskee cup saucer (to stop the cup slipping?), and the speaker above the door entertaining us with 80s music, the natural connection here was graphene.

Graphene is a form of carbon that is a single atomic layer thick. Each carbon atom is arranged into a flat hexagonal structure exactly like graphite but, unlike graphite, there is only one layer of these atoms in graphene. The strength and strange electrical properties of this material, together with its lightweight form, have made this material an intense subject of research for the past 15 years or so. A recent Physics World podcast tested a set of headphones with the vibrating membrane made of graphene. The idea being that the strength of the material combined with its relatively low mass, would enhance the way that we heard the sound coming through the speakers. You can listen to the review (though not the speakers) here.

coffee Hammersmith
Each layer of bricks forms a regular set of layers. But where they come up against each other discontinuities are formed. These can cause special problems in sheets of graphene.

But are there aspects of graphene that may be more applicable to the cafe and coffee industry? Various teams around the world have been working to make membranes of graphene work as single molecule detectors. The idea is that molecules adsorbed onto the surface of a graphene membrane change the electrical properties of the membrane to an extent that can be measured even in the case of single molecule adsorption. The sensitivity of the electrical properties of the graphene to different molecules could mean that graphene based devices would make very sensitive contamination detectors, including allergen detectors. Such sensors are the subject of a research collaboration at the National Physical Laboratory in Teddington and could mean that, rather than be in any doubt as to whether a substance contains an allergen, it could be quickly tested by passing it through a graphene sensor.

All this is quite far from the coffee and cakes at Carbon Kopi. But if you are in the area, it is a lovely place to stop, enjoy a coffee and contemplate the bricks of the church opposite.

Carbon Kopi is at 11 Margravine Road, W6 8LS