reduce reuse recycle

Micromanaging plastic waste

Thames, South bank, London Eye, plastic pollution, Thames21, PLA
Each year Thames21 and the Port of London Authority remove 200 tonnes of waste from the Thames. How much more gets washed into the sea?

Five items make up 2/3 of all lightweight identifiable waste collected from the Thames each year. These items make their way either through being dropped, sometimes deliberately littered, or through another path, into the river where, without litter picks, they are eventually washed out to sea. Part of the estimated annual ~10m tonnes of plastic waste entering into the oceans, they end in one of the gyres of the oceans, vast expanses of sea covered by floating rubbish.

Only much of this waste doesn’t. Or at least not as much as we think should do and we don’t know why. Despite the fact that there is an estimated 250 000 tonnes of waste floating in places such as the North Pacific Gyre, this is not as much as is expected. In fact, the visible waste makes up only a few percent of the waste that is expected to be there. Where is the rest of the waste, and what does it have to do with physics, or indeed coffee?

One of the ‘top 5’ items found in the Thames (coming in at number 4) is take away cups. This is followed closely by take-away containers. This means that our behaviour on leaving cafes, restaurants (and pubs) is affecting the litter that ends up in the river. And this is without counting the fact that food wrappers and drinks bottles (including water bottles) are two of the other worst offenders. It is not necessarily that people are deliberately throwing the items onto the pavement as they walk (though there is that too of course). The charity Thames21 that organises river-side clear ups and litter picks also thinks that some of the waste is coming as a result of people trying to put items into over-filled bins or so-called “tidy litterers“. But the truth is, they don’t really understand the route that many of these items take before entering the river system.

Discarded litter, can holder, litter
Some litter that finds its way into the oceans is merely discarded like this 6 pack can holder. Reducing this getting into the oceans is helped by fewer people littering, more people picking up what they see discarded and changes to the product itself.

It is a significant problem for us now as many of us are trying to support local restaurants or cafes by ordering take away and even when a place has drink-in space, often it is single-use disposable cups that are used. Part of this is understandable. There is a hygiene concern, even if there are counter-arguments that re-usables are safe to use in these times of Covid-19. But I don’t want to trivialise this concern, partly because people are making very hard decisions about how to keep their businesses going or earn enough to pay the next set of bills. If there is any doubt about the safety, it needs to be considered holistically by those running and working in the businesses and not those like me able to work from home and able to get delivery or pop-in and pop-out (and, in fairness, it is easy to see from a barista’s point of view that handling an untouched single-use cup and giving it in a contactless way to a customer is safer than receiving their re-usable container in whatever state of cleanliness it is presented in).

This part seems a question of balance. Balancing the need for economic support with the concerns of the single-use plastic problem. Do the places that you frequent use recycled (and recyclable) plastics or compostable ones? If the latter, is there a compost bin within the cafe to help with the disposal of these? Ultimately, is your take-away coffee going to help the business or are there other items that you can purchase that don’t require the same amount of packaging.

These are considerations with no easy answers which leads to the second approach that you could take. In non-Covid times, charities such as Thames21 are always looking for volunteers to help with clean ups and to get involved in counting the types of litter that find their way to the rivers. Becoming a ‘citizen scientist’ in this way helps to quantify the amount of waste entering our rivers but it also helps Thames21 and the river authorities to understand how the waste gets there in the first place. Why are our river banks so filthy?

Coot nest, plastic waste, Grand Union Canal, litter, plastic pollution, effect on wildlife
A coot building its nest with twigs and litter, including plastic litter, on the Grand Union Canal in London in 2019.

But then the last question. If we know that so much waste is getting into our river, and we know that this is being replicated around the world, why is so little of it making its way to the gyres? What is happening to it?

This affects, to some extent, what we do about our plastic behaviour – the decisions we ultimately make about whether to have a take-away coffee or whether to buy a disposable or re-usable face mask (or even make one). One of the explanations is that the majority of the plastic is becoming micro plastic (<5mm size pieces) or even nano plastic and so sinking into the seas rather than floating on the surface. These micro plastics are the result of the break-up of larger items by UV and micro organisms at sea and also the direct pollution of micro plastics into the sea by clothes being washed or from cleaning products etc. Indeed, the Thames21 citizen scientists discovered micro plastic pollution at 20 out of 21 sites along the river bank in a recent litter survey. A different explanation is that the plastics that are entering our seas today take years, even decades to reach the gyres which are made up of plastics from the 1970s and similar aged pieces. Both explanations mean that we need to stop the pollution at source, but if it is the former, there is not so much point in cleaning up the gyres by pulling the large litter out – the majority of the plastic that is in the oceans is actually underneath what is visible.

Refill station
Water stations and refill bottle. Many of these have been designed to avoid any contact between your reusable bottle and the tap allowing a safe way of travelling with reusables.

How can we determine what plastic waste goes where? Well, we can increase the modelling of ocean currents to improve our ideas about how waste is transported from source to gyre, but we can also try to have a look from space, from the satellites that are monitoring other aspects of our behaviour on Earth. Now it turns out that it is not easy to see plastic from space because with many of the techniques we would use, such as radar, plastic and water ‘look’ very similar. But one thing that that the satellite data has shown is the fact that there are peculiarly calm regions of sea near the gyres. Calm sea looks different from choppy seas in the same way that the light reflected off your coffee looks different if you are sitting with it calmly or if you are running with it and it is sloshing around the cup. But the connections go a bit further than this. The reason for the calm is because of surfactants on the surface of the seas. These surfactants (like soap) ‘calm’ the waves in much the same way as oil calms the waves. It doesn’t take much surfactant to cover the surface of a large area of water as a consideration of how much oil covers the surface of your coffee can tell you.

The surfactants are produced by microbial activity, the result of small bits of plastic (micro plastics) having been colonised by microbes before it sinks. The calm regions of the sea may therefore be indicating areas of hidden micro plastics and demonstrating the depth of the problem of single use plastic waste.

What does this mean for your take-away coffee, your Deliveroo order or your disposable mask? A recent study suggests that it is imperative that we take a combined approach, both as consumers, and as producers, reducing, reusing, recycling and changing the system. But on a personal level of course, some answers are clearer than others. Having an idea of the size of the problem, and the things that we can do to mitigate or understand it, may help us to navigate this plastic minefield.

Half way through…

talesfromthewormbin

What packaging does your coffee come in? Is it paper, compostable? The bits of packaging here are part of an experiment to see how long they will take to break down in a worm composting bin #talesfromthewormbin

The problem is oat milk. If you are having a go at living plastic free (or even reducing your reliance on single use plastic) during Plastic Free July, you have probably encountered at least one sticking point. Something that you are finding a little tricky to let go of. There are things that are too difficult to eliminate right now (meat/fish packaging is one example although there have been efforts to change this in some locations) but these are not necessarily sticking points. No, sticking points are things that seem that they should be easy to eliminate but for some reason are not. For me this is oat milk.

For the past three years, I have been participating in Plastic Free July with the aim of trying to find ways of living that reduce my plastic waste. And for the past three years, the problem has been oat milk. It is becoming a bit of a nemesis. Although proper, dairy based milk is available in glass bottles, this does not appear true for non-dairy based milks. Although some packaging can be recycled, it is a significant contributor to my waste pile. So, how about home made oat milk? It should be easy shouldn’t it?

oat milk, kone, filtering

Oat milk filtering through the Kone filter.

You can find plenty of recipes for oat milk online (a few are here, here and here) but I’ve always found it messy and, well, wasteful. The worms have enjoyed the oats in the past but surely there’s something better that can be done with them? Well, this year, things seem a bit different. And part of that is because of a coffee filter.

Years ago I tried the coffee Kone filter as an attempt to reduce my use of paper filters in the chemex. Sadly, I didn’t get on with the Kone. Unlike a paper filter, some sediment made it through the filter leading to more of an immersion type coffee drink rather than a filter. Consequently it went to the top of a cupboard and lay forgotten for a few years. Until this June when I re-discovered it as a filter for the oat milk. Rather than a muslin bag, the Kone can be cleaned easily and the whole process is significantly less messy (and slightly quicker – stirring the contents of the Kone with a spoon is easier encouragement to get the oat milk through than squeezing the muslin bag). Although there remains significant work before this can start to be a habit rather than just for a month, this July’s oat milk is a lot more promising than previous years. I’ll keep you updated as to whether the oat milk remains being home made in August.

pitch drop oat milk

Preparing your own dairy-free milk also offers new opportunities for watching physics such as the pitch-drop experiment here.

In the meantime, do let me know how you are getting on with your own Plastic Free July. Do you have any sticking points? On the other hand, are you finding that you are enjoying taking your re-usable cup around with you when you get a take-out coffee? Also, if you have any recipes for things that can be done with these left over blended oats. I’d love to hear of your culinary experiments.

In the following recipes, because I do not know how much oat milk you are making, I’ll call the amount of blended oats X g. In my experiments X has been either 115g or ~60g.

 

Oat and Apple Tarts

Xg blended oat left overs

Xg sugar

X/2 g flour

Pinch cinnamon and nutmeg to taste

teaspoon baking powder

Cooking apple (peeled and cut into smallish chunks)

 

Mix the blended oat left overs with the sugar and then stir in the flour, baking powder and spices. Spoon onto a greased baking sheet so that they make circular blobs of about 3cm diameter. Place the apple pieces into the mixture and bake at 180C for about 15 minutes until risen and slightly browned.

 

Sort of Flapjacks

X g blended oat left overs

X g sugar

X/2 g flour (but this isn’t really necessary).

Oat flakes, spelt flakes, sunflower seeds, pumpkin seeds, dried fruit, whatever you would like to put in a flapjack

Mix everything together, spoon into a lined and greased baking tin, bake at 190C for 15 minutes until firm. Keeps in an airtight container for days.

 

Hobnobby biscuits

home made oat biscuits

Not quite there yet. If you have a better recipe or can improve this one, please let me know.

A work in progress – the quantity of oats is not right yet and perhaps they need to be toasted oats or even spelt flakes.

X g blended oat left overs

X g sugar

X/2 g flour

teaspoon baking powder.

X-2X g oats

Mix the blended left overs, sugar, flour and baking powder together. Stir in the oats. Spoon on a lined and greased baking sheet so that you get ‘biscuit sized’ portions. Bake for 25 minutes at 190C or until brown.

 

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.