kct285

Presentation Feedback: 

During the presentation, I went through my various experiments, findings and final thoughts. Points such as how much was my overall cost, would the milk casein affect flavour of the drink and sustainability of these bottle caps were brought up. 

Professor Marcela’s feedback rings true that in order to create a more sustainable product, there needs to also be a balance between the price point and how many times a product is going to be used. Although these bottle caps were functional, there is still a problem that milk is expensive and having to create one bottle cap that is only going to be used once then disposed of, would be too expensive. 

In the future, I would try to focus more on this fact of realistically considering pricing and duration of usability than on the idea of trying to solve disposable products. In an ideal world, we would be able to use whichever resources we have to make our items more biodegradable, however in reality, there is always some sort of cost that would overrule the importance it being biodegradable. 

Nonetheless, I’m still proud of my work and experimentation as I not only learned how to make bioplastics but I learned a valuable lesson in that finding alternatives for plastic is far from easy. It’s extremely easy to criticise and demand the use of biodegradable alternatives. However, this problem is so much more complex as it requires the product to not only be biodegradable but also cheap and easily massed produced — far from an easy task. 

Final Thoughts/Conclusion: 

Overall, from my experiments, I can conclude that milk can be used as bottle caps. I can see these being implemented in Shanghai and other places as it is easily mouldable and in an industrial setting could definitely be formed into very nice bottle caps that function just as well as our current ones. As such, this could be a more biodegradable product than the current plastic ones that are not able to be recycled and become plastic waste as milk casein is an all-natural product. 

Through milk casein bottle caps, this will hopefully be able to raise awareness on the complexity of recycling. This was something that I learned a lot from this semester because of this class and I think is very important for everyone to know as well. I’m sure that not a lot of people are aware of how recycling works and furthermore, not aware that a lot of products are made with different types of plastics that can’t all be recycled. Through seeing these bottle caps, consumers become more aware of this fact and be more conscious of the way they consume and throw away trash as it is more complicated than just throwing trash in the right bin classification. 

However, there are still problems such as how milk casein is not vegan and still harmful for the planet through still having to take care of cows and other mammalian livestock — contributing to tonnes of greenhouse gases and loss of land. Also, there is a problem that milk is expensive and in order to obtain casein, a large amount of milk has to be used and hence, sustainability is called into question. These milk bottle caps would possibly be more useful in countries where they have a lot of open land and hence, a lot of cows and milk such as Mongolia. Some countries have a surplus of milk which allows them to obtain milk easier and at a cheap price, allowing them to also make more milk casein plastic. Moreover, even in other places where milk is expensive, these milk bottle caps can still be made as a statement to still educate people on the complexity of recycling. These bottle caps don’t have to be made on a big scale and replace bottle caps but perhaps just for an educational display that is able to  attract people and get them to know more about plastic recycling. 

If I had more time, I would do further experiments on how to make the mould of the milk less fragile and breakable through experimenting on when to remove the casein from the mould. I would’ve also liked to try to make an actual bottle cap mould and see the difference with using that vs. just moulding the casein onto the bottle. This might also strengthen the end result. Finally, I chose to not explore soy milk as many sources online stated that plant-based milks wouldn’t work but as seen from the experiment of Cassie, this was proven to not be true. Given more time, I would hope for a plant-based milk bottle caps that would work as well as plastic bottle caps. 

 

Thank you! 

I would just like to thank Professor Marcela once again! With every class I attended throughout this semester, whether it be a lecture, guest talks or readings, I always learned something new about plastic, trash and the way we consume. I now see trash in a very different light than I did previously and I’m a lot more conscious about the complications and problems of the trash that we make and the ongoing search to find alternatives. I hope to see this class continuing to be taught as it sheds light on very serious and very real problems that our generation is facing and will face. 

Hypothesis: Would milk plastic bottle caps be able to act as a more sustainable alternative?

Once again, using the original procedure, I heated milk, added vinegar, squeezed out the liquid and moulded the milk plastic onto a plastic bottle. From learning from the last experiment, moulding was much easier as I knew what to expect and how to mould to a water bottle. I found that by splitting a piece of dough into 2: moulding one part as a long piece and the other piece as a flat circle was the easiest way to mould the milk casein onto the water bottle mould. 

As this is my final experiment before the presentation, I decided to make 4 bottle caps to see which would turn out the best.

Results:

After waiting 2 full days, I removed the bottle caps from the mould. Interestingly, my initial thought of waiting longer before removing it from the mould may not be right after all as I found more cracking than my previous experiment. Hence, there is space for further experiment and research on when is the right time to remove the casein from the mould.

 

Furthermore, this experiment also emphasised how important the thickness of the casein is when placed on the mould. Whilst drying the casein does shrink up so one of the bottles which had a thinner layer of casein, completely cracked. 

Change of plans:

During last week’s lecture, Professor Marcela brought up how milk plastic was already used before in order to make various beads and buttons. Initially, I was planning to make a cup holder out of milk plastic. However, I started to realise how much milk I would actually need in order to make one cup holder.

From previous experiments, I realised that a lot of milk was needed in order to obtain a small amount of casein. My previous experiments, using 500ml milk, resulted in not even half the amount of casein I needed in order to make one cup holder. To make one cup holder, I would then have to use at least 1 litre of milk along with 16 tablespoons of vinegar. This does not include the casein that would crumble off during the moulding process, a situation that often reduced the initial amount of casein even further. When applied to the real-world situation, no one would ever continually use litres and litres of milk just to make a few cup holders that would be discarded after one use. This would be unrealistic and continuing with cup holders would be an inefficient waste of time and effort on my part as well. 

Hence, with this in mind, I decided to change what I was going to do with my milk casein plastic experiments. Yet, I didn’t want to make small decorations or trinkets with these milk plastics as I wanted to try to contribute to solutions for more sustainable disposable items that we often use. Even though single-use plastics are extremely detrimental to the environment, it would be idealistic to believe that everyone would completely stop using them as they are simply too convenient.

From various lectures and research, I learned how there are different types of plastic in a single plastic bottle. The actual plastic bottle is able to be recycled as it is type 1 PET plastic. However, the bottle caps are not able to recycled and discarded. As there are as many bottle caps as there are bottles — this still creates tons of plastic waste. Due to the bottle caps small size, I decided that this would be a better product to use with milk plastic. Bottle caps are still a disposable product that is often used once and never again. From this information and small size, I decided to try to make bottle caps out of milk plastic.

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Hypothesis: Can milk plastic be moulded to usable bottle caps?

I started googling some methods on how bottle caps were made. Unfortunately, since many people don’t make bottle caps, the majority of the search results were how to recycle bottle caps. Whilst interesting, these were not helpful. I just hoped for the best, using actual bottles as the mould and started my experiment.

Using the original procedure from the last 2 experiments, I heated milk, added vinegar, squeezed out the liquid and started moulding the milk plastic onto a plastic bottle. This proved to be much trickier than I expected. At first, I the milk casein dough kept cracking and breaking off due to how small and wide the opening of the bottle was. Due to this, I decided to switch to a milk carton as the hold was smaller in width but taller in height, which allowed a more solid base for the bottle cap.

After some careful moulding and smoothing out the cracks, using some skills I used from a previous pottery class, I moulded the milk casein onto the opening. As I had extra milk casein, I tried to experiment with an alternative bottle cap, a kind of plug that is often used in wine bottles.

Results:

After about a day and a half of drying, I attempted to take the milk plastic off of the mould. It was able to be taken off and kept the mould of a bottle cap. However, in the process of taking it off, some cracks deepened and tore. 

On the other hand, the alternative bottle cap plug failed as it shrunk. Also, texture was too hard and not ‘squishy’ enough to be a sufficient bottle plug. 

 

Reflection & Next Steps: 

Although the bottle cap tore a bit when I took it off the mould, it generally worked quite well as a bottle cap with gentle twisting and tugging. However, it is still quite fragile as a bottle cap. 

The bottle cap plug was a fail and the milk casein texture is not suitable for a bottle plug, so I wouldn’t be continuing to experiment on this. 

For the next steps, I will wait longer than 2 days before attempting to take off the bottle cap in order to give the milk casein more time to dry and harden and I will also try to mould the milk casein more evenly onto the mould. Both of these would hopefully reduce the likelihood of cracking and breaking. 

 

Hypothesis: How does the amount of vinegar and type of milk affect milk casein produced?

For this second experiment, I did some further research and found a couple of different suggestions and tips from people online:

1. Soaking the milk curd in vinegar will make the curd smoother, less crumbly and easier to mould
2. Using more vinegar will create more milk curd
3. Other types of milk such as buffalo, sheep and yak have more/less casein than regular cow milk

From this new information, I wanted to experiment and try it out to see how much truth there was to these tips. Hence, I modified my original methodology with 3 different experiments:

1. After separating the curd, dump it in again in vinegar for 1 hour before moulding
2. Doubling the amount of vinegar added (12 tablespoons to 500ml of milk)
3. Use yak milk

Results:

For the first round, I used much more vinegar than I did for the first experiment. Expecting larger chunks of curd to form, I instead saw the mixture to be very powdery and less chunky. This was confirmed as I placed the milk through the strainer. Most of the milk past threw and I only attained a small amount of curd. This was surprising as I used double the milk from the first experiment but was only able to attain approximately the same or even less curd.

For the second round, I followed a similar original methodology, but just added the curd into a bowl of vinegar to soak. At the 30 minute mark, I checked on it and saw the curd has become very powdery once more and became smaller. By the time the hour was up, half of the curd has become small powder and I was left with a very small amount of curd that wasn’t even that easy to mould, just very sticky and wet.

In the last round, I managed to find 200 ml yak milk on Hema. I followed the original methodology and attained the same amount of milk curd as when I used 500 ml of cow’s milk which I was extremely impressed with. It also seemed much easier to mould and less crumbly.

Amount of curd left just from 200ml of yak milk

1. Cow milk (500ml)
2. Yak milk (200ml)
3. Cow milk soaked in vinegar for 1 hour 

 

Results: 

cow milk after 2 days

Although the 200ml yak milk produced approximately the same amount of milk casein as 500ml cow milk, I found that even after 2 days of drying, the casein produced was much oilier than the cow milk. This may be due to the higher percentage of fat in the yak milk. Furthermore, as it was oilier, I found there were more cracks and would be easier to break than the cow milk which fully dried. 

yak milk after 2 days

I learned that some of the myths found online may not be exactly true or I did it wrong as I found that soaking the milk casein in vinegar for the extra hour did make the casein a bit smoother, but it also significantly reduces the size of the casein clumps as it dissolved even further in the vinegar. 

Moving forward, I decided to stick with cow milk. However in order for me to make a cup holder, I’d have to use a considerable amount of milk and perhaps make a mold. 

Hypothesis: How does milk brand/quality affect the casein plastic produced?

For my first experiment, I decided to try out different brands of milk with varying quality. I judged the quality of each milk by their expiration dates and prices. Through some research, I learned that the more processed the milk, the longer the shelf life and in general, the cheaper the price.

The 3 brands I bought were: 德业纯牛奶 (‘worse’; expiration: 1 year)，光明纯牛奶 (‘medium’; expiration: 6 months) and 维纯牛奶 (‘best’’; expiration: 3 months). From the initial research I found out, no one mentioned whether the quality of milk would affect the casein curd formation. Hence, I want to explore this to see if I’ll be able to create better/worse variations of casein with different milk brands. Out of curiosity, I decided to also buy a chocolate milk to see what would happen. I didn’t have much hope in much casein being extracted as chocolate milks are often diluted with sugar and water, but it would have been cool if it were to work.

Ingredients & Equipment:

• Milk (4 brands)
• White vinegar
• Pot
• Hot top stove
• Stirring spoon
• Strainer
• (A lot of) Paper towels 

Methodology:

1. Heat 250ml of milk in a stove top until it is steaming hot.
2. Add four teaspoons (tsp.) of white vinegar.  The milk should form white clumps curds
3. Mix the milk slowly
4. Stack several layers of paper towels on a flat surface
5. Once the milk and vinegar mixture has cooled a bit, pour the milk and curd into the strainer
6. To make sure all curds are attained, pour the milk through the strainer once more
7. Gently use the spoon to scoop out the curds onto the paper towels
8. Fold the edges of the paper towel stack over the curds and press down on them to absorb excess liquid. Use extra paper towels if needed to soak up the remaining moisture.
9. Knead all of the curds together into a ball, as if it were dough.
10. Leave it to dry on paper towels for at least 48 hours. Once it has dried, the casein plastic will be hard.

 

Results:

I found that the ‘worse’ quality milk created the least amount of casein compared to the other brands. The ‘medium’ quality turned out to be whiter than the rest. Whilst the ‘best’ quality milk resulted in the same amount of casein as the ‘medium’ but seemed to be harder and stronger after the 2 days of drying than the ‘medium’, but not by that much.

Both the ‘worse’ and ‘medium’ milk brands were easier to break than the ‘best’. Hence, moving forward I will continue experimenting with the ‘best’ milk brand.

The chocolate milk was one big fail. No casein were ever big enough to stay in the strainer. 

Reflection:

Whilst doing the process, I was surprised by how wet the curds are and how much paper towels I had to use to soak up all the moisture. By the end of this first experiment, I gone through most of the kitchen tissue roll which I found quite wasteful. I’ll try to perhaps use a towel next time to see if that would work in order to save some tissue.

I also found moulding the casein to be very time-consuming. Some of the casein were very crumbly and so it kept falling apart. Moulding and kneading the dough for a long time had to be done in order to reduce the crumbling.

Also since For this first experiment, I did not think of having a pin roller; however for next time I would try to use of some sort to make sure the casein dough is spread out enough. This meant that the middle stayed wet as it was very thick and didn’t harden. This led to the milk plastic to be less strong and vulnerable to cracking.

Even though I attained interesting results that confirmed my hypothesis, I only did this experiment once. However, due to time constraints, I will be proceeding ahead with my next experiment, working with more varieties of milk and quantities of vinegar.

(From left to right: 3,1,2) 

From my proposal, I decided to focus on milk casein plastic. Before starting my experiments, I scoured the Internet for any current information that could help with my exploration of milk casein.

Science Behind It:

Milk is made up of proteins, fat and water. Many of the proteins are made up of casein. When combined with vinegar, the milk forms curds which can be separated and moulded. These curds are actually long chains of the casein protein molecules called polymers – the same building blocks as plastic.

Currently Available Information:

First of all, vegan milk such as soy, oat or almond milk cannot be used when making milk plastic. This is because casein is a protein that can only be found in mammalian milk such as cows and sheep. It is an essential amino acid that provides calcium and phosphorus for skeletal growth. Hence, although I would have loved to experiment with and use plant-based milks in this process, I decided to skip out on it as I knew these milks did not contain the casein protein I needed for the plastic.

I also found that different vinegars can be used to separate the casein protein in the milk, just as long as acetic acid is present. This means that apple cider vinegar, white vinegar and wine vinegars can be used. However, for the purposes of this experiment, I will be using white vinegar as it contains the most acetic acid amongst the list, 4-7%, and it is also the cheapest 🙂

According to Wikihow, whole milk or heavy cream will work the best then 1% or 2% milk. This is probably to do with the amount of casein in the different types of milk. Hence, for this experiment, I decided to use whole milk for the entirety of the process.

Next Steps:

With the information I found, I decided to use 3 different types of whole milk. I have not come across any information on how the quality of milk would affect the casein; however, I would hypothesis that the better quality milk would also result in better quality casein plastic. I picked 3 different milk brands — with all varied in qualities, judged through the different expiry dates. Through my knowledge of food, I would assume that the longer the expiration date, the more processed and lower quality the milk is.

Inspiration:

Whilst researching, I stumbled upon “Tomorrowmachine”. This is a Swedish company who came out with a line of sustainable food packaging called “This too shall pass”. They also used all natural materials such as sugar, wax, oil and agar. This set of food packaging really caught my attention as it not only decomposed together with the food, but it had an incredibly creative, innovative design. 

A Look at Creative Food Packaging

Proposal:

For my final, I really want to focus on food/beverage packaging. Just from a quick Google search, no matter which site you go to, food packaging always comes out as the top of the list of plastics in oceans and our natural environment. It is something that I also find extremely frustrating in my everyday life. Now that I do my own grocery shopping every week, I am reminded of how much unnecessary plastics that grocery stores and companies package their food in.

Idea #1 — Fruit Styrofoam Packaging

During last week’s lecture, our group conducted an experiment involving agar and made a thin sheet of plastic. I’m hoping to use this concept to recreate fruit styrofoam. One of the pieces from Tomorrowmachine’s  line of sustainable packaging features a juice box made out of agar. It was very jelly-like which would be the perfect material to protect fruit.

Hypothesis:

Is it possible to make agar bioplastic that thick and have it be able to be wrapped around the fruit?

Is there a more innovative way to protect fruit, reducing the amount of materials needed to be created?

Can this fruit styrofoam be reused into something else before it is decomposted?

 

 

Idea #2 — Milk Casein Cup holders

Tessa Silva-Dawson currently makes a series of cups, vases and other vessels using this the casein of milk. From the images shown on her website and online, it’s quite surprising how she made these beautiful pieces all from milk. Hence, this is not only something that is more sustainable, but customers would be willing to purchase it just from the design of it alone. 

Tessa Silva-Dawson uses milk as substitute for hydrocarbon plastics

One of the most convenient, but another very wasteful form of packaging are beverage cup holders. Professor Marcela herself is working on potential ones right now using coffee for the 2F cafe’s metallic cups. I also want to try to make these cup holders, except using the milk casein. I did some research on this bioplastic in another week where this method has actually been used before our modern plastic. Hence, I know that this is a solid way to make bioplastics. What would be problematic is whether or not this material is the best as a cup holder. 

Hypothesis:

Would this material be suitable as cup holder?

How would it fair with very hot or cold drinks?

Would additional cloth or other materials be needed?

For this week’s lecture, we were divided up into groups to make different kinds of bioplastics. Our group, consisting of me, James and Joyce, were in charge of creating bioplastics out of agar, glycerin and water.

The process of it was simple and straightforward enough. We combined all the ingredients together then heated this up to 95 degrees Celsius, stirring all the way through the whole process. Then poured thinly onto a tray to dry for a couple of days. We found that this method of making bioplastic is extremely easy, but also extremely time-consuming. At the end of class, we were not able to get our agar solution to 95 degrees, just 70 degrees. We have yet to see how this might have affected our bioplastic.

From this experiment, I was excited by the thought of this new, innovative alternative for plastic. Yet, I also wondered why this is still not often used or produced by companies as there is already some solid research on these bioplastics. It wasn’t until I read “The truth about bioplastics” that I realised there were still a lot of unresolved problems. For example, although bioplastics are still much better than regular plastic, it still needs high temperatures in specific composting facilities in order to break down. This required investment in these specific composting facilities and many countries do not have the money or the resources for this — creating a barrier for poor, developing countries.

Moreover, there is also the issue of many of the bioplastics still emitting greenhouse gases as it involves the production of crops. It would also be competing with the food industry and would need vast amounts of land in order to produce the crops. From this article, it is clear why these bioplastics are not able to be fully manufactured in a large scale as further research still needs to be done.

From lecture and Precious Plastics workshop, we learned from Professor Marcela and Adele that the type of plastics that can be recycled are types #1, #2, #4 and #5, however, the best would still be #2. Adele was able to show us the different types of plastic products that Precious Plastics were able to make. I was surprised how they were able to create many different kinds of textures, using the same plastic, and just changing the method of melting and moulding the plastic.

When ground up into pellets, these plastics are able to be melted and transformed into whatever we want — in our case, we used these plastics to make the base of the stool. For this, we needed a lot of plastic. To do this, we had to first sort and cut up the plastic into smaller sections. Then, this would be placed into the shredder to become plastic pellets. After waxing down the mould, we placed the pellets in, stacking them past the top of the mould. This was because as the plastic melts, it will decrease in size. After taking it out of the oven, the plastic must be pressed down immediately to take the shape of the mould whilst still warm, then given time to cool down.

Besides this, we also used pellets under the heat press. This resulted in flat pieces of plastic, similar to the ones Adele demonstrated to us earlier in lecture. Although they came out a bit too early and didn’t full flatten and form, I was still very impressed by how this could now be something usable.

Readings:

The text “Social Innovation in China” emphasises on the importance in making businesses and NGOs who are making innovative, positive social impact products be more scalable. It is through this that we are able to reform the way we produce and consume. This is especially so in a country like China where the economy is still developing and growing at a phenomenal speed. Governments have the opportunity to easily implement regulation and reforms in order to encourage these social innovations and educate people on the importance of this whilst they are still developing. From just living in China and seeing the Trash Classification system being put into play, I believe that if the Chinese government wanted to, they could easily implement regulations that would force companies to think about sustainability. It’s just a matter of waiting until they start prioritising the environment over economic growth.

The text “Multiple-Helix Collaboration for the Development of a Circular Economy”

For this “circular economy” to develop, the 4 stakeholders: government, NGOs, consumers and companies all have to collaborate and work together to create positive social impact. NGOs and companies must strive to create innovative products, and not just profit. Governments would then need to aid them in scaling and promoting these NGOs through subsidies and regulations, which would then help influence consumer choices.

Beach Clean Up:

When we first walked into the park, I was a bit confused as to what we were doing there. Everything seemed so clean already. However, it was only when we walked to the edge, towards the seaside, did we see the piles of trash. Large pieces of styrofoam, plastic bottles, cigarettes and clothing scattered the rocks.

After an orientation and debriefing from Green Initiatives, we were divided into small groups, each collecting a classification of trash. Me and Joyce were in charge of collecting residual trash. This meant we collected various small pieces of plastics, bottle caps and a good number of shoes. Although we only picked up trash for less than 2 hours, we found it to be very interesting, yet a very exhaustive activity as we were forced to face the consequences of human ignorance and lack of care for what we consume.

I’ve seen piles of trash my entire life — whether it be on streets of Manila or in the AB throwing away my 外卖。However, it’s a different situation having to pick up trash and sort them as it really emphasised how this concept of “single-use” is a complete lie and delusion. Nothing is single use as it still exists and doesn’t simply disappear. Every single piece of item that we produce, whether it be a shoe or lighters, is going to be thrown away eventually and eventually, it will make its way back to us.

Learn from China

Some Chinese crafts that can be useful in our plastic exploration could be the art of folding Chinese fans. From the workshop, plastics could be melted and become different textures and thickness/thinness. This may perhaps be able to be done with plastic as it could be molded when fresh out of the oven. 

 

Find References:

1. Milk Plastic

A protein found in milk called casein. When extracted, it is able to form plastics. This technique of making plastic was used previously but went out of style for more long-lasting, hard wearing petrochemicals. According to “Bio thinking”, this would definitely be a cyclic product as it is naturally from milk protein. However, this form of plastic may not be very efficient as it requires heating milk and getting the small amount of casein protein from it.

Make Plastic From Milk? You Can With Science!

2. Seaweed water bubbles

There have been a few companies who are attempting to create edible water bubbles made out of seaweed to replaced plastic bottled water. One of the companies is Ooho, a UK startup who claim to manufacture these using 5x less CO2 and 9x less energy than PET production. According to “Bio thinking”, this product would be both cyclic and efficient as seaweed is part of the natural environment and more efficient than PET manufacturing. However, there may be concerns over the safety of this product as it claims to also be edible but that may cause some health problems down the line.

the ooho! edible water bubble gets set to replace plastic bottles

3. Prawn shell plastic bags

Science fair winner, Angelina Arora demonstrates how chitosan can be extracted from the carbohydrate chitin and chemically converted from prawn and crab shells. This breaks down completely within 33 days. According to “Bio thinking”, this plastic alternative is also cyclic and made from materials that would be thrown away. However, it may not be very efficient as well as prawn shells come in different sizes, weight, etc and could be harder to scale up.

https://www.nationalgeographic.com/environment/2018/09/angelina-arora-teenager-created-plastic-shrimp-science-fair/