Categories
Coffee review Coffee Roasters Observations slow Sustainability/environmental Tea

Cobwebs, Crows & Coleman Coffee, Lower Marsh

filter, Brazilian or Guatemalan, V60, rainbow, glass, Coleman Coffee, Lower Marsh, Waterloo
There’s a lot of physics in this glass cup of coffee, enjoyed at Coleman Coffee, Lower Marsh.

Coleman Coffee on Lower Marsh, Waterloo, is a surprisingly relaxing place. Surprising because the frontage gives little away. A door with windows on either side revealing a small wooden bench on the right and a larger table on the left. A food menu is on the left, the coffee menu in front of you (above the counter) and a note about how the coffee is roasted on a black board on your right. The space feels open and welcoming but it is the garden at the back that I think shifts Coleman Coffee from being a lovely little café to a great spot at which to just spend time and notice things.

My first visit was on an incredibly hot day in early July. For some reason I didn’t see the filter coffee option on the menu and so chose a long black to enjoy outside. The shade of the trees was a welcome respite to the hot Sun and the contrast created by the light provided much to dwell on with the inadequacies of my phone’s camera. Berries had formed on the tree growing up the wall of the café. After my visit I read the review of the café on Brian’s Coffee Spot and realised that these berries were mulberries. The other trees providing the shade were a Jasmine and a Pomegranate. I also found that I had missed the filter option and so a return visit was obligatory! How easy it is not to notice things.

ditch the plastic straw, enjoy a paper one
Chocolate milk and a paper straw.

A second visit sadly revealed the restricted opening hours of Coleman Coffee. Arriving at about 2.58pm, we were told it was take-away only as they were closing at 3pm. However the third visit was worth the wait. By this time the weather had turned and it had been raining, but the garden was still calling. The filter coffee on offer (V60) was either a Brazilian or a Guatemalan. Opting for the nuttier of the two (an allergy to actual tree nuts does not prevent my enjoying nuttiness in coffee!), we took a couple of glasses of water through to the back and awaited our drinks. When they arrived, it was interesting to find that the nutty coffee was truly nutty. A lovely flavour and mouthfeel to enjoy. It was also great to notice that the straw in the chocolate milk seemed to be an old-fashioned paper straw (rather than the environmentally problematic plastic straws). As it had rained, the stools outside were a little wet, even though they had been largely sheltered by the same trees above the garden. This time, the mulberry tree seemed mulberry-less, apart from the one berry lying sorrowfully on the floor. The red of the berry being squished (accidentally) underfoot leaving it lying and injured in the style of Pyramus and Thisbe. Across the other (wetter) side of the garden, three spiders were busy weaving new webs, ready to catch whatever flies came their way. It would have been easy to watch those spiders for hours but I think a good café can linger in the memory long after your visit has ended and so the spiders are still spinning their webs in my mind now.

garden spider at Coleman Coffee Waterloo
Spider on the table. What could be better than time spent contemplating their webs?

Photos of spiders webs glittering with dew drops are common place but somehow strangely attractive. Beads of dew gather at various points on the web leading to descriptions of cobwebs as being laden with jewels. A few years ago, a scientist contemplating spider’s webs asked why it was that water collected like jewels on the webs? Why didn’t it collect similarly on your hair? (You can read more about his story here). The team looked at the webs of one particular spider with an electron microscope. Electron microscopes can magnify things far more than optical microscopes (for images of coffee under an electron microscope click here) and so the scientists were able to observe how the hydrophilic (wet-able) fibres in the web turned from ‘puffs’ to ‘knots’ as they got wet. Water falling on the web was then attracted to these knots, partly due to an effect caused by the knot shape and partly due to the surface tension gradient of the water along the fibres. The results of the study can be found here.

Although it took five years of investigation after the initial contemplation, this study of spider’s webs could lead to tools that could be used for water collection or in devices to aid chemical reactions. Which brings us to the other ‘C’ of the title: crows. Sadly there were no crows in the garden on either of my visits to Coleman Coffee. Nonetheless there is a link. My first visit had been cut a little short as I was headed to the Royal Society Summer Science Exhibition. Apart from the fact that it was baking hot inside the Royal Society, this science outreach event had a good mix of science/experiments for adults and for kids, it was great to wander around and learn a large number of new things. So many exhibits caught my eye but the one that connects with Coleman’s and cobwebs was the exhibit on tool making crows.

Spider and web, Coleman
Spider building a web at Coleman Coffee

Crows have been shown to be great tool users. Particularly the New Caledonian Crow which has been shown to even make hooks out of twigs in order to fish out insects from their hiding places. While thinking about what it was that led to this species of crow becoming adept at tool use (and therefore perhaps an explanation of human tool use), it became apparent that the two particularly good tool using crow species lived on remote islands without predators. Not only did they have the physical ability to create tools (a straight beak for crows, a thumb for humans), they lived in a place where they could have time to explore and to create, to develop tools to enable them to get the most tasty bug.

Just as the scientists had needed time to watch, to investigate and to think about spiders webs in order to create new tools, so crows may have needed that time to explore their tool use. Perhaps it’s worth pushing the analogy to inner-city London (or indeed wherever you are). The more we spend time out, contemplating and enjoying nature, the more productive we can be. But to develop, we need to slow down, to think, to contemplate, and to enjoy great coffee in surroundings as special as at Coleman Coffee.

Coleman Coffee is at 20 Lower Marsh, SE1 7RJ

Categories
Coffee Roasters slow Sustainability/environmental

Good news on coffee bag recycling & re-using air valves

air valve, plastic, environmental coffee packaging
Air valves and metallised plastic are common packaging materials for freshly roasted coffee.

Hopefully we’re all trying to reduce our environmental impact but there are things that we can’t seem to avoid. There is the saying “reduce-reuse-recycle”, but how do we do that with coffee bags? Can we reduce? How would we reuse? And recycling has, until now, seemed impossible.

The problem is that in order to keep freshly roasted (and particularly freshly ground) coffee fresh, it is packed in metallised plastic bags normally with an air valve. Metallised plastic is not recyclable in the general waste stream and so the air valve, even if it is made of a technically recyclable plastic material, is unlikely to be practically recycled.

There are questions as to whether it is necessary to package coffee in this way. A blind taste test by the Nottingham based coffee roaster Roasting House showed that, if your coffee was freshly roasted, a (recycled and recyclable) paper bag was a good option for packaging. Although the flavour profile was different for coffee stored in a bag with an air valve compared with the paper bag after 1 week of storage, the benefit to the taste did not seem to be worth the environmental cost if the coffee is delivered fresh to the customer (within 24 hours or so).

However, perhaps the roaster that you buy coffee from prefers to use the traditional metallised bags with air valves. What can be done there? Fortunately, there has recently been some great news on this front. Has Bean coffee have teamed up with TerraCycle to offer recycling of Has Bean coffee bags. TerraCycle are a company that specialise in recycling (or reusing or up-cycling) hard to recycle materials, such as coffee bags and coffee capsules. TerraCycle takes materials such as coffee bags and either repurposes them (TerraCycle’s website mentions repurposing juice pouches by sewing them together to make rucksacks) or pelletising them to be made into other plastic products.

Earth from space, South America, coffee
Our common home. Can we keep our coffee habit while keeping our home safe for future generations?
The Blue Marble, Credit, NASA: Image created by Reto Stockli with the help of Alan Nelson, under the leadership of Fritz Hasler

Sadly (but understandably), to take advantage of Has Bean’s offer to recycle your coffee bags you have to be a Has Bean customer. However, all is not lost. If you are not a Has Bean customer you can purchase your own recycling box from TerraCycle for coffee bags (prices start from £73*) or coffee capsules (prices start from £72.36*). Perhaps it is something out of the range of the general consumer but it may be something that smallish coffee roasters with a network of cafés could consider stocking? Do you regularly buy your coffee from a cafe? Why not ask them if they will consider TerraCycle? If you drink coffee from larger companies such as, Tassimo, L’OR and Kenco, there are (free) collection points for their packaging nationwide.

However, what if you don’t buy coffee from either Roasting House or Has Bean nor have easy access to a TerraCycle recycling box? There is one more option in the 3-r’s: re-use. To consider this question, I’ve been experimenting recently with a coffee bag with an air-valve (left over from Roasting House’s experiment that they were happy to send me, thanks Roasting House). Could the air valve be re-used as a valve for fermentation?

Lacto-Fermentation has been in the news a lot recently for the health benefits that it may have. However it is also an interesting and easy way of preserving almost any vegetable. The idea is simple. Mix the vegetables to be preserved in some salt water, store them in a jar and leave them for a few days. That’s it. The salt kills the harmful bacteria while allowing the bacteria that is good for us, the lactobacillus, to thrive. These lactobacillus also produce lactic acid that preserves the vegetables for many weeks while giving them that slightly sour taste of sauerkraut and kimchi.

lacto fermentation, airvalve, air valve, reduce reuse recycle
Can you use coffee bag air valves as one-way lids for fermenting vegetables?

A problem with fermentation seems to be that if you tightly seal the vegetables in a jar, the build up of gas during the fermentation process could mean that the mix explodes. If you open the jar every day to let the gas escape, you may well end up with mouldy cabbage rather than delightfully acidic sauerkraut. This is where the coffee bag air valve comes in. Could you replace the lid with a coffee air-valve and so allow the gas to escape while not having to open the lid every day?

Replacing the glass lid of a Kilner Jar with a lid made from a ring of cardboard (lined with the coffee packaging) and then the coffee bag with air valve seemed to work at first. As had been predicted, my first attempt at fermented spring greens (where I opened the lid each day) had resulted in mouldy cabbage. Successful fermentation came when the glass lid was replaced with the air-valve construction. Could there be a re-use for the air valve?

fermented cabbage
Fermented spring greens. These vegetables have been fermented with salt.

To check whether the valve worked as planned, I used it as a lid for a jar containing bicarbonate of soda and vinegar. As anyone who has played with these substances for making rockets or model volcanoes will know, combining these two substances produces a lot of gas. Again, nothing exploded. However, sadly (?) nothing exploded either when I sealed the air valve with sellotape and repeated the bicarbonate of soda/vinegar experiment. A quick inspection revealed air-gaps between the cardboard ring and the air valve lid and while these could be sealed quite easily, the air valve never seemed to be the primary outlet valve for this set-up.

So, a failure? A null result? Perhaps, but perhaps not. The air valve structure did mean that I was confident that I didn’t have to open the lid on the fermenting cabbage and the cabbage did not turn mouldy before it fermented. Unfortunately, it is hard for me to eat enough fermented cabbage to justify having repeated this experiment enough times yet to be certain! So this is where you come in. Why not have a go at making your own sauerkraut, kimchi or indeed any pickled vegetable (apart from potatoes apparently). Re-use that air valve while reducing food waste. If you do so, please do let me know your design and how it worked (and of course any good fermented vegetable recipes). Alternatively, if you have found another use for those old air valves, or know another coffee roasting company that is recycling its packaging or making efforts to move to  more sustainable packaging, please do let me know in the comment section below, on Twitter or on Facebook.

Enjoy your coffee and your lactobacillus.

*prices correct at time of writing (18th July 2017). Please check TerraCycle’s website for most recent prices. If you are outside the UK, the international website of TerraCycle can be found here.

Categories
Coffee review Science history slow

Coffee & temperance at the Penny, Old Vic

inside the Penny Old Vic
Coffee at the Penny

A café with good coffee in a theatre? I admit to being a little dubious when I first read about Penny at the Old Vic. Fortunately, there was no reason to be concerned. Penny serves Workshop coffee in an unusual setting (even accounting for the fact it is in a theatre). Going through the doors to the Old Vic, you turn left and head down a staircase to the basement where a long counter stretches out in front of you and to your right. Being a theatre café, there were a wide selection of snacks, bar meals, beer and wine in addition to the coffee being served with the La Marzocco espresso machine. As you’d expect, the usual range of coffees were on offer but if you prefer non-dairy milk, there was oat and almond available in addition to the more usual soy based milk. (Although almond milk is one to watch for if you have a tree-nut allergy as there is a risk of cross contamination).

There was also a wide selection of chairs and tables to choose from, ranging from a standard table, to a high table with stools and, around the corner, some chairs that look like you can sink into them and enjoy your coffee way after the performance has been called. The café is open all day (in fact from 8am until 1am on week days) and, if you are not there during a performance is quite spacious (though during the intervals it could probably get quite crowded).

staircase, Old Vic
The lighting on the staircase periodically got brighter and then dimmer. How easy is it to keep our national electrical supply constant such that blackouts and brownouts are not a problem?

The café certainly provides a service for good coffee in Waterloo (it’s within 5 minutes walk from the station) and it is a great place for refreshment if you are visiting the theatre, but is it also the sort of place at which you can slow down and enjoy the moment? The type of neighbourhood café where you can sip your coffee while letting your mind wander onto a café inspired thought train? At first glance, it is perhaps unpromising as it has clearly been renovated and made to be a modern café. But then, thought trains do not happen “at first glance” but as a result of slowing down, sitting, watching and absorbing the surroundings. It is as you do this that I think Penny at the Old Vic starts to speak to you.

The first thing that you may notice is the lighting. A number of different types of lightbulb including an industrial looking art-piece on the stairwell coupled to what appeared to be natural light coming down through another staircase. This theatre was first built in 1816-1818¹ (but with significant rebuilds since then), how was the stage lit at that time? Where did the theatre patrons go to get a cup of coffee or a glass of wine between the scenes and how could they see anything in the dark?

Around 3.5 miles away, one of the first housing developments to have electric lighting was being constructed in the 1860s. The electricity was supplied by seven steam engines housed in a building just off High St Kensington and sent to the new development next door, “Kensington Court”¹. Evidence of the electrical power station (which supplied DC not AC electricity) can still be seen on a stone sign on the building alerting passers by to the “Electric Lighting company”. It is probable that no such set of steam engines provided power for the lighting in the Old Vic, which was more likely still run on candles and gas lighting. However, it is something that was nearly contemporary with the development of Kensington Court that gives this post its title. It is also the reason behind the name of the cafe.

Soya hot chocolate at the Penny, Old Vic
Lord Kelvin got thinking about viscosity as a consequence of drinking a hot chocolate.

In the 1880s, a woman called Emma Cons took control over what is now the Old Vic. When she ran it, the theatre was called the “Royal Victoria Hall and Coffee Tavern” and ran ‘morally decent‘ productions for local people (note though the importance of the coffee to the project!). These productions included scientific lectures for which the entrance fee was a penny, hence, apparently, the Penny café. Apparently she also ran science classes in the disused dressing rooms and, though the mind boggles as to what experiments were done in this theatre at that time, the classes and the lectures were so popular that soon, Cons founded Morley College to continue this adult education. Morley College continues as an adult education college to this day and is now one of London’s oldest adult education colleges.

So it would appear that, even though the Penny café is a relatively new addition to the Old Vic theatre as we know it, the associations between the theatre and coffee (and the theatre and science) go back a long way. First appearances can be deceptive and, with good coffee and much to ponder, the Penny is definitely one to sink into a chair and to listen.

Penny café is in the Old Vic Theatre, The Cut, Waterloo, SE1 8NB

Inside the Penny
Penny at the Old Vic.

¹The London Encyclopaedia, 3rd Edition

Categories
General Home experiments Observations Science history slow

Theme on a V60

bloom on a v60
V60 bubbles. There is much to be gained by slowing down while brewing your coffee.

Preparing a coffee with a pour-over brewer such as a V60 is a fantastic way to slow down and appreciate the moment. Watching anti-bubbles dance across the surface as the coffee drips through, inhaling the aroma, hearing the water hit the grind and bloom; a perfect brewing method for appreciating both the coffee and the connectedness of our world. The other week, while brewing a delightful Mexican coffee from Roasting House¹, I noticed something somewhat odd in the V60. Having placed it on the kitchen scales and, following brewing advice, measured the amount of coffee, I poured the first water for the bloom and then slowly started dripping the coffee through. Nothing unusual so far and plenty of opportunity to inhale the moment. But then, as I poured the water through the grind, I noticed the scales losing mass. As 100g of water had gone through, so the scales decreased to 99g then 98g and so on. It appeared the scales were recording the water’s evaporation.

science in a V60
Bubbles of liquid dancing on the surface of a brewing coffee.

It is of course expected that, as the water evaporates, so the mass of the liquid water left behind is reduced. This was something that interested Edmond Halley (1656-1742). Halley, who regularly drank coffee at various coffee houses in London including the Grecian (now the Devereux pub), noted that it was probable that considerable weights of water evaporated from warm seas during summer. He started to investigate whether this evaporating vapour could cause not only the rains, but also feed the streams, rivers and springs. As he told a meeting of the Royal Society, these were:

“Ingredients of a real and Philosophical Meteorology; and as such, to deserve the consideration of this Honourable Society, I thought it might not be unacceptable, to attempt, by Experiment, to determine the quantity of the Evaporations of Water, as far as they arise from Heat; which, upon Tryal, succeeded as follows…”²

Was it possible that somehow Halley’s demonstration of some three hundred years ago was being replicated on my kitchen scales? Halley had measured a pan of water heated to the “heat of summer” (which is itself thought provoking because it shows just how recent our development of thermometers has been). The pan was placed on one side of a balance while weights were removed on the other side to compensate the mass lost by the evaporating water. Over the course of 2 hours, the society observed 233 grains of water evaporate, which works out to be 15g (15 ml) of water over 2 hours. How did the V60 compare?

Rather than waste coffee, I repeated this with freshly boiled water poured straight into the V60 that was placed on the scales. In keeping with it being 2017 rather than 1690, the scales I used were, not a balance, but an electronic set of kitchen scales from Salter. The first experiment combined Halley’s demonstration with my observation while brewing the Mexican coffee a couple of weeks back. The V60 was placed directly on the scales and 402g of water just off the boil was poured into it. You can see what happened in the graph below. Within 15 seconds, 2 g had evaporated. It took just a minute for the 15g of water that Halley lost over 2 hours (with water at approximately 30 C) to be lost in the V60. After six minutes the rate that the mass was being lost slowed considerably. The total amount lost over 12 minutes had been 70g (70ml).

evaporation V60 in contact with scales
A V60 filled with 400g of water just off the boil seemed to evaporate quite quickly when placed directly on the scales.

Of course, you may be asking, could it be that the scales were dodgy? 70g does seem quite a large amount and perhaps the weight indicated by the scales drifted over the course of 12 minutes. So the experiment could be repeated with room temperature water. Indeed there did appear to be a drift on the scales, but it seemed that the room temperature water got moderately heavier rather than significantly lighter. A problem with the scales perhaps but not one that explains the quantity of water that seems to have evaporated from the V60.

control
Hot water (red triangles) loses more mass than room temperature water (grey squares).

Could the 70g be real? Well, it was worth doing a couple more experiments before forming any definite conclusions. Could it be that the heat from the V60 was affecting the mass measured by the electronic scales? After all, the V60 had been placed directly on the measuring surface, perhaps the electronics were warming up and giving erroneous readings. The graph below shows the experiment repeated several times. In addition to the two previous experiments (V60 with hot water and V60 with room temperature water placed directly on the scales), the experiment was repeated three more times. Firstly the V60 was placed on a heat proof mat and then onto the scales and filled with 400g of water. Then the same thing but rather than on 1 heat proof mat, three were placed between the kitchen scales and the V60. This latter experiment was then repeated exactly to check reproducibility (experiment 4).

You can see that the apparent loss of water when the V60 was separated from direct contact with the scales was much reduced. But that three heat proof mats were needed to ensure that the scales did not warm up during the 12 minutes of measurement. Over 12 minutes, on three heat proof mats, 14g of water was lost in the first experiment and 17g in the repeat. This would seem a more reasonable value for the expected loss of water through evaporation out of the V60 (though to get an accurate value, we would need to account for, and quantify the reproducibility of, the drift on the scales).

V60 Halley
The full set: How much water was really lost through evaporation?

Halley went on to estimate the flow of water into the Mediterranean Sea (which he did by estimating the flow of the Thames and making a few ‘back of the envelope’ assumptions) and so calculate whether the amount of water that he observed evaporating from his pan of water at “heat of summer” was balanced by the water entering the sea from the rivers. He went on to make valuable contributions to our knowledge of the water cycle. Could you do the same thing while waiting for your coffee to brew?

Let me know your results, guesses and thoughts in the comments section below (or on Twitter or Facebook).

¹As this was written during Plastic Free July 2017, I’d just like to take the opportunity to point out that Roasting House use no plastic in their coffee packaging and are offering a 10% discount on coffees ordered during July as part of a Plastic Free July promotion, more details are here.

²E Halley, “An estimate of the quantity of vapour….” Phil. Trans. 16, p366 (1686-1692) (link opens as pdf)