Category: Sustainability/environmental

Categories
Coffee review General Observations Sustainability/environmental Tea

Reduce, Re-use, Recycle at Attendant

The outside of Attendant on Foley St
Attendant Coffee, Foley St

I was not initially going to do a cafe-physics review of Attendant. It wasn’t that I didn’t enjoy the coffee, I did. I had a very well prepared V60 which went very well with a lovely chocolate brownie. Nor was it that there was nothing to see at Attendant. No, it was quite the opposite. Part of the point of the Attendant seems to be its location. You see, if you were not aware of it already, Attendant is to be found in a (no-longer-used), underground, gentlemen’s toilet. Although they have been thoroughly cleaned, various fixtures (19th century urinals and cisterns) remain in place. Modern (deliberate) graffiti adorns the walls as you walk in. Understandably, there are no windows to gaze out of in this café. It is, in many ways, a very interesting place to visit and the coffee is certainly worth a visit too. However, it is difficult to do a review which is, after all, about noticing something unusual, when the former use of this space is almost shouting at you. I thought about doing a review based on how the shape of the coffee cup can influence the flavour of  the coffee that you perceive. Yet somehow, writing a review on anything other than the fact that this is a re-use of an interesting space seemed, almost, perverse. So I left it. Until that is, UK Coffee Week came along.

UK Coffee Week raises awareness and money for Project Waterfall which in turn aims to help provide clean water and sanitation for coffee growing communities. Currently, Project Waterfall works in three countries, Tanzania, Rwanda and Ethiopia. In these countries a large number of the rural population lack basic access to drinking water while a greater number do not have access to sanitation facilities. Clearly this can lead to health problems. The World Health Organisation estimates that world wide, the drinking water of 1.8m people is contaminated with faeces, while 0.5 million people per year die from diarrhoeal diseases including cholera.

Interesting glassware at the Attendant
Interesting presentation. Coffee at the Attendant.

Perhaps, while sitting in cafés or having breakfast at home, we have a tendency to take water for granted. Certainly I will admit that I can. I’m sitting here writing this enjoying a great cup of coffee with a few biscuits both of which took water to produce. Beyond the obvious water in the kettle for the coffee and the water used for the dough for the biscuits, there is the ‘hidden’ water. The water used to irrigate the coffee crops and the wheat fields or to process the coffee cherry towards the green bean stage. The water used in generating the electricity used to bake the biscuits, or roast the coffee. The water used to clean the utensils between coffee roasts/biscuit batches so that we don’t get food poisoning. The list could go on. Indeed, the UN estimates that producing 1 cup of coffee requires 140 L of water. This figure though presumably cannot include the private water needs of the individuals who work on the coffee plantations. We all need water and we all need it to be clean.

So, in thinking about our water consumption (and the water consumption of those who help us to enjoy our coffee), we can do a few things during this coffee week 2016. Firstly, we could make a donation towards the work of Project Waterfall (here) or a similar charity that is working to provide clean water and adequate sanitation to those who don’t have it. Secondly, we could take the prompt from Attendant and start to think about where our water comes from. Why from Attendant? Well if you were living on the International Space Station or, to a lesser degree, in Singapore, this question may have an obvious answer. For the rest of us, we are often a little bit removed from direct water recycling, but it’s worth looking more closely at Singapore because they have developed a water strategy that may be of use for more of us in the future.

Reclaimed water NEWater, Singapore
30% of water supplied in Singapore is ‘reclaimed’. Where does your drinking water come from?

Singapore has a population of just over 5.5m (London: 8.6m) with a land area of 719.1 km². As an island, it is surrounded by water and so you may think that water is not a problem for the inhabitants of the city-state. But the water surrounding Singapore is the salt water of the sea and so not easily converted into drinking water. While looking for a solution towards a self-sufficient water supply, Singapore decided to try the recycling route. Through a scheme called NEWater, currently 30% of Singapore’s water supply is from  ‘reclaimed’ water (for reasons that may be obvious, they avoid the word ‘recycled’). The Singaporean authorities aim to make this 55% by 2060. Waste water produced in Singapore undergoes a process of micro-filtration (which takes out suspended particles), reverse osmosis and UV disinfection before being reintroduced to the water supply system. Although most of this reclaimed water is used for industrial processes, the reclaimed water can be added to Singapore’s reservoirs so that it will go into the drinking water supply.

A similar process is used on the International Space Station but there, as it is a closed environment, it is not just the waste water that goes down the drain that is ‘reclaimed’ but the water exhaled by the astronauts and the lab animals on the station. On Earth this would evaporate into the atmosphere, contribute to cloud formation and then rain back down closing the greater water cycle in that way. On the space station, the fact that it is a closed environment means that this moisture too can be ‘reclaimed’. By recycling the water in this way, the inhabitants of the space station avoid having to require too many costly water deliveries from the Earth.

Perhaps, while drinking our coffee (or tea, or even water) today, we can take five minutes to consider where our water comes from as well as considering whether those who contribute to our brew have adequate water supplies themselves. And as it is coffee week, here is that link again to Project Waterfall (Donation button at the bottom of the main Project Waterfall page). Enjoy your coffee.

Note added August 2017: It is with some regret that I have to say that Attendant is not a good place to go if you suffer from allergies. They have started serving almond milk and (according to a Twitter Direct Message received from the Attendant Team) do not adequately clean their steam wand between drinks so as to prevent cross contamination. Their advice to me was that I “should not have any hot drinks or food at our premises as we do not operate a nut free environment at our stores”. There are many good cafes to visit if you suffer from nut allergies, but please avoid this one (or just have a black coffee and enjoy the atmosphere).

 

 

Categories
General Home experiments Observations Sustainability/environmental

Clouds in my coffee

clouds over Lindisfarne
How do clouds form?

Does your coffee appear to steam more next to a polluted road than in the countryside?

This is a question that has been bothering me for some time. Perhaps it seems an odd question and maybe it is, but it is all about how clouds form. Maybe as you read this you can glance out the window where you will see blue skies and fluffy white clouds. Each cloud consists of millions, billions, of water droplets. Indeed, according to the Met Office, just one cubic metre of a cloud contains 1 hundred million water droplets. We know something about the size of these droplets because the clouds appear white which is due to the way that particles, including water droplets, scatter sunlight. Clouds appear white because the water droplets scatter the sunlight in all directions. In contrast, the particles in a cloudless sky scatter blue light (from the Sun) more than they scatter red. Consequently, from our viewpoint, the scattered light from the clouds appears white while the sky appears blue. The sort of directionless light scattering that comes from the clouds happens when the scattering sites (ie. the water droplets) are of a size that is comparable to, or larger than, the wavelength of light. This means that the water droplets in a cloud have to be larger than about 700 nm in diameter (or approximately just less than a tenth of the size of the smallest particle in an espresso grind). The particles in the atmosphere on the other hand scatter blue light more than they scatter red light because they are smaller than the wavelength of the blue light. You can find out more about light scattering, blue skies and cloudy days, with a simple experiment involving a glass of milk, more details can be found here.

glass of milk, sky, Mie scattering
A glass of (diluted) milk can provide clues as to the colours of the clouds in the sky as well as the sky itself

So each of the one hundred million water droplets in a cubic metre of cloud is at least about a micron in diameter. We can then estimate how many water molecules make up one droplet by dividing the mass of a droplet of this size by the mass of one water molecule. This turns out to be more than 1000 million water molecules that are needed to make up one droplet of cloud. So, 1000 million water molecules are needed for each of the 100 million drops that make up one, just one, cubic metre of cloud. These numbers are truly huge.

But can so many molecules just spontaneously form into so many water droplets? Unlike a snowball, the water droplet in a cloud cannot start very small and accumulate more water, getting larger and larger until it forms a droplet of about a micron in size. Water droplets that are much smaller than about a micron are unstable because the water molecules in the drop evaporate out of it before they get a chance to form into a cloud (precise details depend on the exact atmospheric conditions). Water droplets need to come ‘ready formed’ to make the clouds which seems unlikely. So how is it that clouds can form?

Condensation on mug in CGaF
Look carefully at the rim of the mug. Do you see the condensation?

It turns out that the water droplets form by the water condensing onto something in the atmosphere. That something could be dust, or salt or one of the many other sorts of aerosol that are floating around in our skies. Just as with a cold mug filled with hot coffee, the dust in the air gives the water molecules a cold surface onto which they can condense. This sort of water droplet can ‘snowball’ into the bigger droplets that form clouds because the water is now condensing onto something and so does not evaporate off again so easily. At the heart of each water droplet in a cloud is a bit of dust or a tiny crystal of salt. Which brings me back to my question. It is much more dusty along a polluted road  than it is in the clean air of the countryside. Is this going to be enough of an effect to affect the probability of cloud formation? Does your coffee steam more as you cross the road than when you walk through the park?

It is a question that demands an experiment (and associated video). Last year, the Met Office suggested this simple experiment for observing clouds in a bottle. Unfortunately however, I have yet to make this experiment work in a way that would allow me to test whether polluted air produces thicker clouds than cleaner air. If you have any suggestions as to a good experiment (that will work on camera!) please let me know either in the comments section, by emailing me, or on Facebook. In the meanwhile, I’d be interested to know what you think, so if you think this post is about you, please let me know.

 

 

Categories
Coffee review General Observations Science history Sustainability/environmental

Keeping it local at Lumberjack, Camberwell

Lumberjack coffee Camberwell
Lumberjack Camberwell with the (not quite) inukshuk in the window

I came across Lumberjack last week while spending an afternoon in Camberwell looking for interesting cafes to “cafe-physics” review. I was actually on my way to a cafe further along the road when a couple of wooden structures in the window attracted my attention. Thinking that they were “Inukshuk” we decided to go in and try this new cafe. It turned out to be a good choice because, even though the structures were not in fact inuksuik, they had brought us into this lovely little cafe. We arrived shortly before closing but I still had time to enjoy a very good long black (with beans from Old Spike Roastery). Complementary water was brought over to the table. It would have been great if we had arrived just that bit earlier so that we could have had more time to properly appreciate this friendly cafe. The interior is bright and smartly decorated with wooden tables and shelving as well as plenty of seats at the back. The wooden furniture is explained by the fact that the cafe is the trading arm for London Reclaimed, a charity that provides employment and carpentry training to 16-25 year olds from SE London while making bespoke furniture from reclaimed timber. The cafe too aims to provide training and support to encourage 16-25 year olds into work and a future career. In terms of the ‘physics’ bit of this review, the interior of the cafe certainly has plenty to observe, from the pendulum like light fittings to the detail of the wood. But as this cafe is metaphorically, and in some ways literally, built on/with wood and as Lumberjack boasts on its website that “almost everything you’ll find in store, from the coffee to the furniture, are sourced as locally and homemade as possible” it is only appropriate that this cafe-physics review should focus on wood, trees and a tree very specific and local to London; the London Plane tree.

Long Black coffee in a red cup
A Long Black at Lumberjack with the grain of the wood showing underneath

With their characteristic mottled bark, London Plane trees are a recognisable sight along many a London street. The bark absorbs pollutants from the street before bits of bark fall off, taking the pollution with them and leaving the tree with its mottled appearance. Their root structure and resistance to pruning or pollarding helps to ensure that (mostly) they can survive happily in the crowded confines of London pavements. They are indeed very much a tree that seems almost specially adapted to London. Yet the connection between the London Plane and London goes deeper than that. The first ever record of a London Plane tree was in the seventeenth century, just up the road from Lumberjack, in the Vauxhall Gardens of John Tradescant the Younger. The London Plane is in fact a hybrid tree, thought to be a cross between the American sycamore (first recorded in London in 1548) and the Oriental Plane (first recorded in London in the C17th). Both these trees were found in Tradescant’s gardens and it is possible that the hybrid tree, the now ubiquitous London Plane, was actually first grown in Vauxhall.

Even though London is full of Plane Trees, it is not very common to find plane wood furniture. Rather than the grain visible in the tables at Lumberjack, Plane wood shows a “lacy” structure that gives furniture made with plane a distinctive pattern. Although unsuitable for outdoor furniture, plane-wood can be used to make indoor furniture and indeed some London based cabinet makers have even documented obtaining usable timber from recently felled London Planes.

Tomb of the Tradescants
The Tradescant Tomb at St Mary’s, Lambeth

And it is this that takes us to the physics part of the cafe-physics review. Perhaps it is the areas (and the parks) that I walk through, but it seems to me that there has been a fair amount of tree felling in London over the last six months or so. Part of the reason for this must be to ensure that the trees in our parks and that line our streets are safe and not going to fall down in high winds. Many trees that fall down in high winds do so because they get uprooted. However it is also possible, in very high winds for the whole tree to snap. Indeed, when researchers mapped the wind speeds through a forested area of Southern France during a storm in January 2009 they found that when the wind speed exceeded ~40 m/s (90 miles per hour), more than 50% of the trees broke in the wind, irrespective of whether these trees were softwood (pine) or hardwood (oak). A very recent paper by a Paris-based group (published last week in the journal Physical Review E) confirmed that irrespective of the species of tree or the tree height, the trunks of trees were liable to snap at a critical wind speed. The team combined experiment and theory to establish that the critical wind speed scaled with the tree’s diameter and height. However, because trees generally treble their diameter as they double their height, the effect of the diameter change was (almost) cancelled by the height difference between trees. Surprisingly, this critical wind speed did not depend on the elasticity of the tree, so there is no difference between a softwood such as pine and a hardwood like oak or plane. The researchers calculated the critical wind speed needed to break a tree to be 56 m/s, very close to the 40 m/s observed in that January storm.

Lumberjack can be found at 70 Camberwell Church St, SE5 8QZ

If you have a cafe that you think needs a cafe physics review, please let me know. Comments always welcome, please click the box below.

 

 

 

Categories
General Observations slow Sustainability/environmental

A drop in the Chemex?

Chemex, 30g, coffee
How do you prepare your coffee?

How do you prepare your coffee? Generally I’ll either use the Chemex or a French press. Often it will be the French press purely because it is, sadly, quicker. However, on those mornings that I do slow down to prepare a Chemex, I generally feel better for it. Not only does the coffee taste better, but those 5 minutes of preparing the coffee pay off as time for the mind to wander rather than just time spent waiting for the caffeine. When the Chemex is nearly ready, the fresh brew drips slowly from the filter onto the liquid below. Each drop produces a ripple pattern. At the start of the UN conference on climate change in Paris (COP21), we may well hear talk of some of our efforts being mere “drops in the ocean”. So it seems a good time to reflect on those “drops in the Chemex”. Just how much influence can a drop  have?

It is worth stopping for one moment to consider what is going on around us at this moment. As I write this, it is late November in the Northern Hemisphere. Taking a walk outside, I can see the last of the yellow leaves falling off the trees. In just a couple of weeks time, many of the trees will be bare. Why do the leaves fall from the trees? We could answer this question in a number of different ways. Biologically, the tree is forming cells at the joint between the leaf and the tree that will eventually enable the leaf to tear from the tree. As these cells are, in some way, responsible for the leaf falling off, they are called “abscission” cells. But even with these abscission cells, the leaf still needs something to force the leaf off. Often this is the wind which is why we get such an abundance of leaf fall on windy days. However there is another mechanism that can help a leaf to drop, and that is a curious interplay between the leaf and rain.

autumnal scene, red leaves, hydrophilic
The surface of the leaf changes from waterproof to ‘wettable’ over the course of the summer

In the spring, many species of tree, including Oak, develop a wax layer on the leaf. Perhaps you have been walking in the country and have needed to wax your walking boots before you go? The wax on the boots acts as a waterproofing for the boot, ensuring that your feet don’t get soggy. The wax on an oak leaf performs the same function for the leaf, it makes the leaf waterproof. Although this is not the only function of the wax. It seems that a waxy surface also slows the processes that dry out the leaf, prevents insects and pathogens attacking the leaves and may even play a role in affecting the way that the light is concentrated into the leaves for photosynthesis. Nonetheless, from the tree’s perspective, it is a significant advantage to have waterproof leaves. Imagine rain falling onto a waterproof surface. The drops of rain do not ‘wet’ the leaves but instead roll off. As the raindrops roll off, they take particles of dust and dirt with them. It is a tree’s way of cleaning itself. Waterproof surfaces are self-cleaning surfaces. Something that some scientists are now trying to replicate for man-made products.

hydrophobic leaves
Some leaves are more waterproof than others.

As the summer continues and the leaf gets older, the wax layer changes. The structure of the wax changes and erodes as the wind, weather and even pollution batter the wax layer. Just as with the hiking boots, the damaged wax layer results in a less waterproof leaf. The leaf becomes “wettable”. When a drop falls on a surface, the shape of the droplet is determined by how waterproof the surface is (more details here). A surface is termed “wettable” when the droplet becomes significantly flatter and coats the surface rather than forming a spherical drop that can roll off. Now consider each raindrop as it hits the different types of leaf. In the spring, the leaf is waterproof and the raindrops will roll off them. A drop of rain will cause the leaf to shake on its stem but then to return to its original position. It is ultimately not affected by a light rain shower. In the autumn when the leaves are no longer waterproof, the rain will start to stick to the leaf surface. Now when the leaf shakes, the wet leaf will not return to its original position but will bend slightly further downwards. As it continues to rain, the leaf will experience a greater torque and this means that it is more likely to fall off the tree. As each rain drop hits the leaf, the likelihood that the leaf will tear away from the abscission cells at the base of the leaf increases. Each drop has an effect.

This also has an important consequence for some of our technology. One renewable energy source that has been proposed for self-powering electronic devices harnesses the energy of rain. When rain falls on an array of cantilevers, it forces the cantilever to bend and to oscillate. This energy can be harvested ( that is, changed into a form that is useful to us) by using small piezo-electric devices (that convert movement into electricity or vice versa) at the  base of the cantilever. When a tree leaf is wet, the leaf joint experiences a greater torque which causes the leaf to ultimately tear from the tree. For the rain-energy harvesters, this is exactly what we want. The greatest energy obtainable from the cantilever system will be from cantilevers that can be made wet. Waterproof cantilevers would be a bad idea. A renewable energy that comes from rain would definitely be a positive development for UK energy production!

It seems that one coffee drop does indeed go a long way.

 

Categories
Coffee Roasters Sustainability/environmental Uncategorized

Plastic, coffee and ethical consumerism

“[W]hile 30% of UK consumers claimed to espouse ethical standards only 3% of purchases examined reflected those standards”∗.

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

Most of us are aware of the growing number of environmental problems facing our planet and many of us want to do something. The question is what? Take the packaging that we use for freshly-roasted coffee. It often comes in metallised plastic bags with aroma valves on the front. Is this packaging good for the environment, or for our coffee?

Many factors will influence our decisions as consumers. Even our ‘ethical’ decisions can be based on different arguments. One factor though is, hopefully, the insights gained from scientific studies on the environmental effects of different types of packaging. Today’s Daily Grind examines some of this science.

Types of coffee packaging available

When you order coffee from a roaster, or buy it at a supermarket, mostly it will arrive in a metallised plastic bag. Some companies will supply coffee in compostable ‘plastic’ packaging, or paper, but most bags are still made from ordinary plastic. Some, larger, coffee roasters supply their coffee in cans. Although these are 100% recyclable, the increased weight compared to plastic packaging and the limited re-usability of the cans mean that plastic packaging can be more environmentally friendly than canned coffee. This article is therefore only going to consider smaller roasters and the plastic vs paper debate.

The problems of packaging

It is helpful to clarify the environmental concerns with respect to packaging. For the case of paper vs plastic, three major areas of concern are:

  • Depletion of a limited resource, recycling and re-usability.
  • Carbon dioxide emissions – in the manufacture and transportation of packaging.
  • Degradability – in both landfill and as litter.

Recycling and the Limited Resource problem

air valve, plastic, environmental coffee packaging
Disposable products make up about 37% of plastics produced‡. Are we wasting limited supplies by wanting our coffee as fresh as possible?

Paper comes from wood but plastics are generally a by-product of the petroleum industry (5% of petroleum in the US is used to produce plastics). Perhaps you will say that not all plastics are made from petroleum by-products. It is true. “Compostable” plastics are typically manufactured from starch based products (corn etc). However other bio-degradable plastics are petroleum based. “Oxo-biodegradable” plastic is ‘ordinary’ plastic with a small amount of catalyst added to it during manufacture. The catalyst causes the plastic to break down more quickly than the conventional plastic without the additive. Typically oxo-biodegradable plastic will be manufactured to degrade after 18 months compared with many years for ‘ordinary’ plastic.

Both compostable and oxo-biodegradable plastic are sometimes called ‘biodegradable’, but there are crucial differences between the two. For the sake of this article, I’ll be comparing ‘ordinary’ plastic with ‘compostable’ plastic (conforming to EN 13432) and oxo-biodegradable plastic (regulation ASTM D6954).

So the first part of the question would be to ask if the coffee packaging is made from recycled material. Paper can clearly be made from recycled material as can ordinary plastic and oxo-biodegradable plastic. Compostable plastic cannot be recycled and so cannot have been made from recycled material.

The second part of the question is whether you can recycle the packaging after using it. Again, paper packaging can obviously be recycled (provided it is not lined with plastic). Although both ordinary and oxo-biodegradable plastic can, in principle, be recycled, the multilayered and metallised design of the coffee bag means that it is not normally recyclable. Some coffee roasters however have started using specially designed plastic packaging that can be recycled in normal recycling centers. It would be great if more followed suit.

Two questions for your coffee supplier: Are the bags used to package the coffee made from recycled material and are they recyclable?

Greenhouse Gas emissions and energy costs

paper bag roasted coffee
Is a paper bag necessarily better for the environment?

Perhaps it is greenhouse gas emissions that concern you and so want to choose an environmentally sound packaging in terms of its CO2 emissions? Paper or plastic? You may be surprised. The environmental cost of a packaging type as measured by its CO2 emissions depends mostly on the energy that is required to manufacture it and the energy that is required to transport the packaging material to the point at which it is used (ie. the delivery of the bags to the roaster).

A few years ago, the Environment Agency performed a lifecycle analysis of different types of shopping bags (plastic, paper, cloth). Plastic bags are typically significantly lighter than the heavier paper bags. So, in addition to the cost of making the bags, it is going to require more energy to transport paper bags to the point of use. The report calculated that the manufacture and transportation of paper bags consumed so much more energy than plastic bags, that paper bags had to be re-used 4 times in order to have the same CO2 emissions as an ordinary supermarket plastic bag, re-used as a bin liner. The situation for a cloth bag was even worse.

Although the plastic used for coffee packaging is much heavier than a standard supermarket shopping bag, the analysis suggests that if your concern is CO2, paper is not necessarily better than plastic. It depends on how you are going to re-use the bags before you eventually recycle them.

Litter and Degradability

I hope that no one is deliberately discarding their used coffee packets onto the street or onto the beach! But litter and bio-degradability are big issues for plastic based packaging materials, particularly at sea. There are horrific stories about marine animals being starved due to consuming plastic or being drowned because they are entangled in it. Paper will degrade very quickly and so clearly does not suffer from the same problems as the plastic packaging in this topic. However, as mentioned above, not all plastic is the same. As well as ordinary plastic, your coffee could come roasted and packaged in a degradable plastic, either compostable or oxo-biodegradable.

sea no litter
There is a big problem with plastic litter ending up in the oceans

The name ‘compostable plastic’ (EN13432) is, to me, a bit disingenuous. It suggests that it breaks down in a composting facility such as my worm bin. But the standard EN13432 does not refer to such home-composting at all. For a plastic to be deemed compostable it has to break down under industrial composting conditions (ie. it is held at 58 C for the period of its degradation). Not all countries/councils offer such facilities for their waste disposal and so a compostable plastic sent to landfill offers little advantage over ‘ordinary’ plastic. However, in the marine environment it has been shown that the compostable plastic bag did degrade quickly relative to ordinary plastic bags‡.

Oxo-biodegradable plastic on the other hand works very differently. At the time of its manufacture, metal-salt catalysts are added to the plastic that determine how long the plastic survives before it breaks down. As long as it is exposed to light and oxygen, the oxo-biodegradable plastic will break down after, typically, 18 months (though the usable time can be made longer than this). Recent studies have shown that it is safe to recycle oxo-biodegradable plastic together with conventional plastic recycling†. Provided that the bag does not get covered in algae, an oxo-biodegradable plastic will break down after 18 months (if that was the time specified at manufacture) whether it is on land or on sea.

Therefore if litter is what you are worried about, you have to ask where you think that the plastics are going to end up and whether you want to be able to recycle them or just re-use them.

So what should you do?

There’s no point me answering this question for you. Ultimately I do not know your individual circumstances and concerns, nor how you are buying and consuming your coffee. Moreover, these considerations have been solely based on some of the environmental problems associated with different packaging. Coffee consumption has other factors, such as the major issue of how the coffee tastes. Earlier this year, Roasting House conducted an experiment to blind-taste the coffee after it had been stored in different types of packaging. You can find the results of that interesting study here.

a take away cup
The next problem. What should we do about take-away cups?

Personally, my concerns are principally the greenhouse gas emissions and the litter/degradability problem. I also buy coffee that is delivered to me very soon after it has been roasted. So I tend to favour packaging that uses unbleached, recycled paper. There is a caveat though. The CO2 emissions caused by paper manufacture and transportation means that I need to find a way to re-use the bags as often as possible before recycling/composting. Fortunately, I think there is a great use for old paper coffee bags: They are the perfect size for carrying loose vegetables or uncooked fish/meat products in supermarkets (rather than use the plastic bags that can be supplied for these products). Each paper coffee bag can be reused multiple times before it finally becomes unusable.

If I were drinking coffee that wasn’t quite so freshly roasted, I would be in favour of using oxo-biodegradable plastic (preferably from recycled material). I do not currently have an opinion on compostable (EN13432) plastic. The results of the degradation of compostable plastic in a marine environment were encouraging and if it starts to become genuinely compostable (as I understand the word in terms of home composting) it would definitely be a type of packaging to consider.

You may come to different conclusions, if you do so, please do let me know what you think in the comments section below. In the meantime, a map of coffee roasters who are trying to improve the environmental footprint of their packaging in a variety of ways can be found here.

 

I am grateful for discussions with Oh Ying Ying of Miracle Spectrum Sdn Bhd who helped me to navigate the minefield of environmental plastics. There is much more to write about plastics, the environment, litter & the Paris meeting, the whole issue of take-away cups for example!

∗ Yeow et al., “Bags for life: the embedding of ethical consumerism” J. Business Ethics, 125, 87 (2014)

‡ O’Brine et al., “Degradation of plastic carrier bags in the marine environment”, Marine Pollution Bulletin, 60, 2279 (2010)

† A report by the Transfer Centre für Kunststofftecknik GmbH (“TCKT”) dated 12 November 2013 on behalf of European Plastic Converters (EuPC), Roediger Agencies.

ª Plastics and the Environment, Ed. AL Andrady, Wiley-Interscience Publications, 2003

Categories
Coffee review Observations Sustainability/environmental

Old and new at Sarnies, Singapore

Sarnies, Telok Ayer St, CBD, Singapore
Sarnies, Singapore

It is just possible that the name ‘Sarnies‘ may suggest a speciality at this cafe in Telok Ayer St. Singapore. And the sandwiches are definitely very good (I happened to visit one lunchtime), but don’t let this deceive you, the coffee is very good too and indeed Sarnies has been listed as one of the top 10 cafes to visit when in Singapore. Sarnies operates from an old style ‘heritage’ building near the central business district in Singapore. This style of “shop-house” used to be ubiquitous in Singapore but as Singapore has developed so the tall buildings of the “CBD” now tower over these remnants of Singapore’s past. The authorities though are keen to preserve their heritage and so many of the buildings have been carefully restored so that the exteriors are fairly faithful to the original. The interior has plenty of table space for you to enjoy your coffee (and sandwich of course) and watch the goings-on around you. Complementary water is available at the bar while you wait for your coffee and sandwich to be brought over to your table.

air vent, natural air circulation, air conditioning
The old air vent system and the new air con unit inside Sarnies in Singapore

Inside, you can see how the demands of modern living have changed the architecture of the shop-house. Above the door, and along the window were a series of vertical timber railings.  These date from the construction of the house and were presumably to assist with air ventilation in a time before air-conditioning. They work because hot air rises and so by putting an opening – a vent – near the ceiling, the  hot air in the building will rise and leave the interior to be replaced by the cooler (it is never cool in Singapore) air from outside. Unfortunately, the temperature in Singapore during the day time is in the 28-33C region and so this method of cooling is not as efficient as air conditioning which is why the vents are now covered in glass. The air-conditioned interior also means that the door of Sarnies is kept closed at all times, ensuring that the air conditioning is as efficient and cool as possible (though seats are available outside should you want to sit in the heat).

coffee at Sarnies Singapore
At the end of the day, it’s all about the coffee

Air conditioning of course needs a lot of energy in order to work. The basics of air conditioning work on the same principles as those that cool your coffee: When a liquid evaporates into a gas it takes energy from its environment and thereby cools it (think about alcohol – or sweat – evaporating from your hand). The issue with air conditioners is that this is a continuous process. The liquid that is evaporated within the air-con unit cooling the room is compressed and re-condensed in the air-con unit outside the shop, in a process that consumes electricity and generates heat which is transferred to the environment outside the shop. The process uses a lot of energy (and therefore generates a lot of carbon dioxide emissions), indeed one organisation in Singapore calculated that more than 60% of their energy consumption on one campus was due to air conditioning.

As cities use a lot of energy, clever design and engineering of the buildings in cities can be used to decrease the carbon dioxide emissions of cities and so help to mitigate the problems of climate change. The C40 is a group of more than 75 of the world’s largest cities that work together to find ways to use urban design to combat environmental problems. Perhaps it is in developing more energy efficient lighting systems or, in the case of the UWCSEA in Singapore, designing their new buildings so that they use air conditioning more efficiently and therefore less wastefully, both in terms of CO2 emissions and in economic terms.

As I was sitting enjoying my Sandwich and coffee in Sarnies, a customer coming into the cafe left the door open. As the hot and humid air started to blow in from outside, the woman sitting near the door closed it to keep the cold in. This small gesture, almost completely opposite to that which I experienced in winter in London last year, helped to ensure that the air conditioning unit did not have to work harder to keep the cafe cool. A small action but one that helps save energy and so the planet, even if just a little bit. If only more of us did this.

Sarnies is at 136 Telok Ayer St. Singapore.

Categories
Coffee review Observations Science history slow Sustainability/environmental

In the Greenhouse at CoffeeGeek

Coffee Geek and Friends, Coffee Victoria
Coffee Geek and Friends

Earlier this year, a new café opened up in Victoria. Coffee Geek and Friends is located at the far end of Cardinal Place as you enter from Victoria Street. Cardinal Place is an odd sort of shopping centre, a small collection of shops with a glass roof. The building site near Coffee Geek as well as the constant stream of people rushing to and fro make Coffee Geek an ideal place to spend some time watching the world go by. Coffee is by Allpress espresso and is served in very individual mugs. Apparently there is a range of geek-ery in the cafe including a ‘centre piece’ water filter but I admit I missed that as I was too focussed on my coffee. Coffee Geek and Friends is definitely a cafe to keep in mind (along with Irish & June’s) if you need a good place to meet near Victoria Station.

It was a very humid day when I enjoyed my coffee at Coffee Geek and, because the mug had not been pre-warmed before my Americano/long black (my notes don’t specify which) was poured into it, condensation quickly formed around the rim of the mug. The condensation forms for the same reason that dew forms after a cool night: the vapour pressure of the water above the coffee (or the ground) has reached the dew point at the temperature of the mug. The lower the temperature, the lower the vapour pressure has to be for the water in the atmosphere to start condensing into liquid droplets. Hence you will often find that your coffee is more ‘steamy’ on a winter’s, rather than a summer’s day.

Condensation on mug in CGaF
Look carefully at the rim of the mug. Do you see the condensation?

Just over two hundred years ago, William Charles Wells made a study of dew. He observed the weather conditions under which dew formed. He observed on which surfaces dew collected. He noted whether the dew formed on space facing surfaces or ground facing surfaces. After several years of careful study he published his “Essay on Dew” in 1814. His work, showed that the earth radiated heat at night (when it was not being kept warm by the Sun) and therefore that space was cold. Cloud cover reduced the amount by which the ground cooled which implied that cloud cover was acting as a type of blanket for the Earth, keeping the heat trapped inside. Later calculations of the balance between the heat radiated by the Earth and the heat received by the Sun confirmed that, without some heat getting trapped by clouds and ‘greenhouse’ gases in the atmosphere, the earth would be a good 30 C cooler than it is observed to be. Although these calculations are just rough, “back of the envelope” figures, detailed calculations confirm that the Earth is in a delicate balance, heated by the Sun, cooled by radiation and kept warm (and live-able) by a layer of natural greenhouse gases. This “natural greenhouse effect” has been necessary for our development, the problem is that now we are adding yet more greenhouse gases to the atmosphere which threatens to tip the established delicate balance by a few degrees.

Cardinal Place roof, greenhouse
The roof of Cardinal Place shopping centre. A very appropriate place for a meditation on the greenhouse effect

What we now call the greenhouse effect are these extra gases, which are more efficient at trapping heat within our atmosphere. If you can imagine what has been happening over the past three hundred years or so as we have been pumping yet more of these gases into the atmosphere at an accelerated rate, we are in danger of tipping this delicate balance towards further heating of the earth. The 2015 Paris Climate Conference is being held with the aim of requiring all nations to agree to a legally binding commitment to reduce the amount of extra greenhouse gases that we emit to a level that will only result in a temperature increase of 2C. To achieve this requires all of us to work together to reduce our own ‘carbon footprint’. Each of us will have to find our own, individual ways to reduce our emissions but perhaps when we look at the condensation on the rim of our coffee cup, we could remember William Charles Wells and his essay on dew and just think, what can I do, at this moment, to reduce my carbon footprint? Maybe it could be something as simple as turning off that phone (to conserve the battery) and watching what is going on in a café instead. A small gesture but one that would be good for us as well as the earth.

Coffee Geek and Friends is at the northern end of Cardinal Place shopping centre (opposite Westminster Cathedral).

As a Coffee Geek note, I would like to just comment that my notes on Coffee Geek and Friends were written using a “linux-sure” ball point pen. Not particularly environmentally friendly but definitely quite geeky.

Categories
General Home experiments Observations slow Sustainability/environmental

An opportunity to become a cafe-scientist

coffee, Timberyard, wooden tray
A great place to sit and do some citizen science: Timberyard, Seven Dials has plenty of seats outside.

There are many things to be gained from putting down your smart phone when you enter a café. Firstly, there is the opportunity to fully experience the coffee. The sounds as it is made, the smell, the taste, even the feel of the coffee. Then there is the opportunity for people watching; their behaviour as they order their coffees or have their meetings or try to alleviate boredom while playing with their smartphones. Of course, there is also the opportunity to look at the history of the café and its surroundings, to think about a café-physics review or just slow down and notice things. There’s always something interesting going on.

If you are lucky enough though to be in Athens, Barcelona, Belgrade, Berlin, Copenhagen, London, Manchester, Milan or Rome there is now even more reason to put down that phone while you savour your coffee. By doing so, you could be helping scientists with a few questions that they have about atmospheric pollutants. If you are not in one of those cities, you miss out this time, but you may want to keep reading because if enough people get involved now, perhaps next time the iSPEX-EU project may come near you.

contrail, sunset
What sort of aerosols and pollutants are floating in the atmosphere above your head at this moment?

The question is, what are the atmospheric pollutants that are in the air near where you are now? Perhaps you are in a café on a main road and the answer seems obvious, it is those cars and buses that keep passing by. But there are in fact many forms of atmospheric aerosols or particles and they range in size from a few nanometers to tens of microns (which, in terms of coffee grind is from much smaller than the smallest Turkish coffee to approximately the size of a small particle in an espresso grind). Is it really so clear that where you are, in the centre of that big city, is that polluted? If on the other hand you are on the coast in Barcelona, just how salty is that salty sea air? The iSPEX-EU project allows you to measure it and find out.

These particles of dust, salt and soot etc. can have  an effect on human and animal health, so clearly we want to know more about their distribution and their prevalence. But there are also, more subtle reasons why we may want to know about them. They may have an effect on global warming and they are certainly needed in order for clouds to form, (though as yet we still do not fully understand this process). We need more data about what aerosols are around and where they are to start to know what questions to ask (let alone answer) about health, the climate and cloud formation. Yes, we have satellite measurements and pollution data at specific locations, but what people are missing is that local information. What are you actually breathing? When you look up at the blue sky, what pollutants (or other type of aerosol) are you looking through? Can we get enough data to know how the air quality varies between the cafés of Hackney and those of Hammersmith?

Skylark Wandsworth
Another ideal cafe for iSPEX-EU measurements, great coffee and a lovely outdoor seating area at Skylark cafe, Wandsworth Common

To get this data the scientists involved in iSPEX-EU need people, many people. People who are willing to spend 5 minutes turning their iPhone (sadly it is an iPhone-only project) into a pollution detector. The more people that they can get measuring, the more data that they will be able to obtain. All you need is an app from the App-store and a (free) device that fits over your iPhone camera which you can pick up from somewhere local to you. Then, you just take a seat outside the café on a lovely blue sky day between now and the 15th October, aim your phone at the sky and take a series of photographs which are shared back with the scientists coordinating the project. If you are curious to know how your air quality compares with that in another participating city, you can check the live map to see how the measurements are going across Europe.

The device works by looking at the colour spectrum as well as the polarisation of the light reaching the camera as a function of angle. This information gives tell-tale clues as to the size of the aerosols as well as their prevalence. There is a lot more information on the website of the iSPEX-EU project and so I would recommend that if you do want to know more, you click their link here. In the meantime, why not sign up with iSPEX-EU, take a seat outside in that café and enjoy a great coffee knowing that, as you do so, you are contributing to our understanding of atmospheric science.

If you do decide to participate, please let me know of any great locations that you find, both for the coffee and the measurements, or share your pollution measurements with me in the comments section. I look forward to seeing some great data on the live map.

To get involved with the iSPEX project, you can follow the link here.

 

Categories
Coffee review Observations Sustainability/environmental

Seeing the trees for the wood at OJO Coffee, Bangsar, KL

coffees on display at OJO
OJO Coffee, Bangsar, Kuala Lumpur

It is very easy to sit for a long time watching the people and the surroundings at OJO Coffee in Bangsar, Kuala Lumpur. Initially I had thought that this medium-sized café with an impressive number of power points dotted around it was an independent. However similarities with CoffeaCoffee around the corner and a couple of other clues (CoffeaCoffee t-shirts) suggest that it is actually part of the CoffeaCoffee chain, something that was confirmed when I asked the barista. However, the standard of coffee in this chain should prompt some of the smaller independents to up their game a bit (and certainly all of the UK based chains). Not content with just serving the typical coffees of ‘latte’, ‘cappuccino’ etc. (which are made using their own blend), OJO’s additionally serves about 15 types of single origin coffee made with your choice of method (Hario V60, Aeropress or French press). For a while this summer I became a bit of a regular at OJO and so I would particularly recommend the Indonesian Sumatran prepared by V60, but with so many coffees to choose from (from the relatively local Indonesians to South American coffees from much further afield) there is plenty to try at this café.

wooden mosaic
The wall made of wood at OJO

The interior of OJOs is decorated with many types of wood. Different cuts of wood are made into a sort of wood mosaic on the wall while the tables are made using several types of wood so as to give a symbolism about the Sun that is a type of motif of the café. Much of the floor is wood too and so this got me thinking about the rainforests in this country. Malaysia has a rich variety of wildlife and forest, it is home to the Orangutan as well as many other species. Teak trees that can be used for more expensive furniture grow along the roadside. Much of this timber can be obtained sustainably and in a way that respects the rainforest and I am certainly not suggesting that the wood in OJOs was anything but sustainable. However, perhaps inevitably, there are many pressures on these invaluable forests. Some of these pressures have, in the recent past, resulted in significant deforestation. One such pressure is that of palm oil.

Palm oil is a massively useful commodity. It is now used in food products from margarine to biscuits to raisins (surprising but true, check the ingredients list of a packet of raisins) and non-food products such as soaps. It is literally everywhere. Both Malaysia and its neighbour, Indonesia, have profited enormously from growing and exporting palm oil. Unfortunately, at times the rainforest is cleared to make way for the palm oil plantations. As it is easier to burn felled trees to clear the land rather than to painstakingly pull the roots up by hand, the cleared forest is burned. But the ground is not any ordinary soil, the ground is often peat based which means that the fires on the surface penetrate deep below the ground and produce phenomenal amounts of smoke.

If at this point you were wondering where the ‘physics’ bit of this café-physics review is, I assure you it is coming. It is indeed linked to this environmental story and to OJOs, please keep with me.

Each year, parts of Malaysia, Singapore and Indonesia are enveloped by a haze produced by this burning peat land (It made the BBC in 2013 when it was particularly bad, but some haze is present for a few weeks every year). Haze has the appearance of thick fog but smells of smoke. At times, visibility can be reduced such that the tops of nearby tall buildings are obscured. Each time land needs clearing for new palm oil plantations, this smoke is produced. The haze can be reduced by local weather patterns but on many days, the haze is cleared by the torrential rains that can occur in this part of the world.

the haze is coming in
L-R: The haze comes in over part of KL in 2013 (series of 3 pictures)

It is commonly said that ‘rain clears the air’ but this is not completely true. It is not the raindrops themselves that somehow wash the air free of the dust of the haze, it is the vortices that form behind them*. Just as a spoon dragged through coffee produces vortices behind it, so a raindrop falling through the air forms vortices in its wake. The size of these vortices will depend on the size of the drop and the speed at which it falls through the air; a tea spoon and a dessert spoon pulled at different speeds through the coffee similarly produce different forms of vortex. So the amount of dust that is ‘sucked in’ and falls to the ground will depend on the type of rain that falls. Perhaps if you are in Malaysia, Singapore or Indonesia when this haze is present, you could make a study of which sort of rain clears the air most effectively. I have an idea but not the evidence to see if the idea is correct, it would be interesting to know what you think.

As I left OJO one afternoon, the rain had started to come down. The rain, or at least the vortices behind the raindrops, cleared some of the haze that had been around earlier. It is a temporary solution to a longstanding problem. A more long lasting solution may be to start (or continue) asking manufacturers of those biscuits you are eating: just how sustainable is the palm oil they are using?

OJO is at No 23, Jalan Telawi 3, KL

* JR Saylor and BK Jones, Physics of Fluids, 17, 031706 (2005)