Science & Nature

May 1, 2017

FROM SHRIMP TO PLASTIC

For some time, during the 20th century, plastic was considered one of Mankind greatest inventions. Ladies and gentlemen from all over the world, used them as a prize, when shopping. Then it became a headache, just before becoming public enemy number one. 

First of all, the terrifying numbers. Take a sit and don't be too scared.

Every year, the United States only, generates 34 million tons of non-recycled plastic. Thus, the Atlantic Ocean won itself its own continent of plastic waste to rival with the Pacific Garbage Patch (and there are four more trash vortexes around the world). In the North Pacific Ocean, fish ingest an estimated amount of 24 thousand tons of plastic every year.

Conventional polythene plastic, made from fossil fuels, lasts between 500 to 1000 years before decomposing. Considering, human being has been using this material for over 40 years, we can calculate the amount of plastic bags there are in the oceans. And we're only talking about regular plastic bags.

Fortunately, some countries are aware of this total ecological disaster and they are taking measures to solve this huge planetary problem. For instance, the United Kingdom has been working hard to create a biodegradable bag industry and, the United States, are starting to ban plastic bags and other forms of plastic materials. Other countries like Taiwan, South Africa and Bangladesh have already banned plastic bags.

One could say: plastic bags are most convenient when shopping and there are already bioplastics made from plants.

Indeed. However, this is not a solution for developing nations, such as Egypt, where most cultivation goes entirely for food and cotton production and processing.

And that's why, researchers and bioengineers at Nile University, in Egypt, are developing a process to turn dried shrimp shells, which would be thrown away, into thin films of biodegradable plastic. Their goal is to obtain a new biodegradable material which will be used to produce reliable eco-friendly grocery bags and other kind of food packaging.

The funds came in September 2016 and, since then, Dr. Nicola Everitt, material engineering professor from the University of Nottingham, in the United Kingdom, has been leading the research team in Cairo, Egypt. So far, they discovered that out of two pounds (less than a kilogram) of shrimp waste, they can produce as many as 15 bags. This could seam short numbers, but given the country imports 3,500 tonnes of shrimp every year, which produce 1,000 tons of shell waste, the numbers are quite appealing.

After six months of the two-year project, the team has managed to create a thin, clear prototype of plastic, using Chitosan, a substance which can be found in the shells of many crustaceans.

Chitosan is already known to scientists. Recently, the biomedical industry has been working with this substance in order to use it in tissue engineering, drug delivery and wound healing.

Processing the shells

For the time being, the researchers buy the shrimp shells from restaurants, supermarkets and local fishermen at low prices. Don't forget we're talking about food waste.

Afterwards, the shells go into a laboratory for the chemical treatment.

The chemical process is quite simple. The shells are boiled in acid to dissolve the calcium carbonate, which is what makes the shells brittle. And then, in order to remove the protein molecules, the obtained substance is boiled, once again, in an alkali solution. This will induce the mixture to turn it into a polymer in the form of flakes. These flakes, can then, be processed into a thin plastic film using conventional manufacturing methods.

Processing the shrimp shells into Chitosan is particularly attractive. The substance is, not only, biocompatible, but it also has antimicrobial and antibacterial properties. In addition, the plastic film absorbs oxygen, making it very suitable for the food industry as it prolongs the shelf life of many products.

Furthermore, people with shellfish allergies don't react to Chitosan.

According to Dr. Nicola Everitt, "so far, the team has only produced small samples of the film and the project is not yet ready to go into commercial large scale production, but the team is working hard to develop properties that would allow the material to go into widespread use".

Right now, the team in Egypt is working to optimize chitosan extraction process, which takes about three days to complete, but "that might come down when the process has gotten a bit more streamlined", Dr. Everitt added.

This process is being worked out, also at Harvard's Wyss Institute for Biologically Inspired Engineering, Massachusetts, United States. For the American researchers, there is no reason why plastic can't be replaced with other biodegradable material. Their option is aiming for the production of Shrilk, made out of Chitosan.

The tests performed in the United States show the material breaks down within few weeks of being thrown away and provides nutrients for plants.

Chitin, the principle of Chitosan, is the second most abundant organic material on the planet and it can also be found in fungal cells, insect exoskeletons and butterfly wings.

Going back to Dr. Nicola Everitt: the "use of a degradable biopolymer made of prawn shells for carrier bags would lead to lower carbon emissions and reduce food and packaging waste accumulating in the streets or at dump sites. It could also make exports more acceptable to a foreign market within a 10 to 15 year' time frame".

More Articles

FeaturedArticles

  • Apple-Sized Diamond, the Second-Largest Ever Discovered on Earth

    Business & Industry

    Nov 30, 2015

    Apple-Sized Diamond, the Second-Largest Ever Discovered on Earth

    A Canadian mining company The Lucara Diamond Corporation has unearthed the largest single diamond found in more than a century, and it's the second biggest ever found.

  • Confael1

    Food & Beverage

    Nov 1, 2016

    THE RUSSIAN "DOLCE VITA" BY CONFAEL

    It is not because of the lack of options that it is so hard nowadays to choose a gift. On the contrary, with the abundancy of nice things at stores anyone can afford, people became very difficult to get surprised with a gift.

    ...

  • Business & Industry

    Apr 1, 2015

    A Leap in urban transit

    Natural gas-fueled buses from private transport company Leap started making their way through San Francisco along the company's first route, dubbed the Lombard Express.


  • HOL21416_Gesamtsortiment_RZ_530px_300_198

    Food & Beverage

    Apr 1, 2016

    Over 80 Years Feeding Babies

    Holle is one of the leading manufacturers of organic food for babies and one of the oldest children food companies in Europe. "Love, protection and Holle," it is with this message that it has conquered parents and babies in over 80 years...

  • Lifestyle & Travel

    Sep 1, 2015

    The American Hospitality

    Carlson is one of the largest privately held companies in the world, encompassing more than 1,370 hotels in operation and under development in over 110 countries and territories and Carlson Wagonlit Travel, a global leader...

  • sunset-114557

    Lifestyle & Travel

    Jun 1, 2016

    WILD CROATIA

    Dominated by postcard-like landscapes, incredible colours and scents, intertwined with the sounds of the pristine Balkan forests and falling water, Plitvice Lakes Natural Park is Croatia's brightest gem, and one of Europe's top destinations...


  • TransCanadaTrail002

    Lifestyle & Travel

    Mar 1, 2017

    TRANS CANADIAN TRAIL - THE GREAT TRAIL THAT UNITES CANADA

    Its construction began in 1992, the Trans Canada Trail has the purpose to unite the extremes of Canada since the Atlantic to the Pacific and the Arctic, and it's about to be completed this Fall, precisely in the year of the celebration...

  • Mahabis-2

    Luxury & Fashion

    Oct 1, 2016

    SLIPPERS THAT PROMOTE WELFARE

    Marketed by mahabis, the XXI Century slippers have italian sole but are produced in Portugal. They stand out in the market for comfort, simplicity and functionality, and are designed to be a reflection of global heritage.

    ...

  • 01

    Culture & Art

    Jun 1, 2017

    COME RAIN OR SUNSHINE

    They're umbrellas, but of paper. They seem to be the result of an advanced origami technique, but in fact it is a very different process, also coming from Japan.