Crustacean shells, insect exoskeletons and fungi may be different by origin. However, they all have one thing in common. All of them produce a wonderful compound called chitin (pronounced as kai-tin). It is a foreign name which leads many to think it is a chemical compound. However, that is not the case. Chitin is a natural substance that is abundant around us. Chitin has a multitude of uses that many will find surprising.
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Shells To Chitin And Chitosan
There is an abundance of chitin when it comes to sourcing for it. Imagine going to your favourite restaurant and craving for seafood dishes. There will be crabs, shellfish, prawns and many more to dig in on the table. But once you`ve satiated your appetite, what happens to these shells? Restaurants dispose of them in rubbish bins which pile up our landfills. Malaysia‘s landfills keep piling up whilst only recycling about 10.5% of those waste. So what can we do about it? Let’s start by reusing some of them instead of throwing them away.
Both chitin and chitosan comes from the same source, shells, exoskeletons and fungi. It is a modified version of polymeric carbohydrates (polysaccharides) which is very similar to cellulose. In that respect, it is an alternative to cellulose in its application to food and many other things. However, the main difference between the two is that chitosan is soluble whilst chitin is not.
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The process of extracting chitin is by removing all protein and calcium carbonate (CaCO3) from shells and exoskeletons. The first method involves using acid and alkaline solutions to dissolve calcium carbonate and protein from the shells. The other and more recent method (for prawn shells) is by fermenting discarded fruits with shells.
Chitin has a hard structure, is resilient and insoluble. Hence a process called deacetylation is necessary to remove an acetyl group from its chemical structure. This makes it soluble whilst still retaining its beneficial properties. This turns it into chitosan.
What Is So Special About Chitin Anyway?
Chitin is a long-string polymer chain that is similar to cellulose. Food companies use chitin to thicken food or as stabilising agents for their products. In fact, chitin is a better alternative to cellulose. A non-chemically altered chitin is also more resistant to certain food processes than cellulose. This allows for a wider range of uses without additional cost.
It also has food preservation properties. How does that work? It basically protects foodstuff from deterioration on a microbial level. Thereby extending the food’s shelf life without adding chemicals. Who would have thought that discarded shells or exoskeletons would still be useful.
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Can Discarded Shells Still Be Beneficial?
Similar with any type of food, moderation in consumption will bring much more benefits than overloading on it. Consuming a good amount of chitin can help our digestive tract. Chitinase is present in our digestive system and it helps break down chitin for digestion. The presence of chitin triggers an immune response which in turn builds up protection against parasites.
We consume fibre to aid our digestive system and promote growth of good bacteria. Chitin is an insoluble fibre which also keeps our gut healthy with probiotic properties. Not only does it keep our gut healthy, it also prevents inflammation in our colons. Apart from that, chitin supplements can also reduce effects of foodborne disease, allergic asthma and food allergies.
From Food To Medicine
Depending on its molecular weight, chitin has medical uses as well. Vaccines work by introducing a weakened virus into the body to stimulate and build resistance to it. Chitin acts similarly but without the virus. Thus its ability to stimulate an immune response makes it a possible additive as a vaccine adjuvant.
Not only does it assist vaccines, derivatives of chitin can help battle obesity. Its helps by lowering blood cholesterol level. Additionally, chitin has antioxidant properties by bonding with free radicals in our blood.
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From Shell To Skin
There are many external applications for chitin as well. Doctors and hospitals are using chitin to help heal wounds faster. Technologies such as chitin-infused bandages and creams have a strict criteria to follow. They have to be a good scaffold for tissues to regenerate whilst also being biodegradable once the process is complete. Chitin fulfills this role well.
Not only does it help our cells heal faster, chitin and its derivatives have been found suitable to be used in anti-ageing masks. A study in 2014 by the Department of Chemistry in Pharmaceutical Science, Complutense University confirmed these findings.
Improving Plant Immune Systems
Chitin is not only applicable to humans but it is also useful in agriculture. Plants build up their immune defences by strengthening their cell walls. Because chitin is a part of insects and fungi, the introduction of chitin into fertilisers triggers an immune response, thereby increasing plant immunity without the actual risk of danger to the plants. As such, the use of organic fertilisers produced from insects such as black soldier fly are picking up.
Shells That Are Helping The Ocean And Our World
We use plastic on a daily basis. There is no doubt that many on the green bandwagon will reduce plastic usage as much as possible. However, we are unable to remove plastic completely from our daily lives. So what can we do about it? Plastic takes centuries to deteriorate. One alternative is using chitin. Plastic packaging made from chitin fibrous structure allows it to degrade much faster. Bioplastics are plastic products that can degrade and decompose in less than one year. Chitin could soon replace traditional plastic bags with its fast-decomposing ability and leave behind a cleaner Earth.
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More Than Meets The Eye
In conclusion, chitin and its derivatives don’t just improve health in humans and plants. It is also useful in sustaining a cleaner Earth by leaving less plastics around. The abundance in source makes it easy to secure, yet we have yet to fully explore its potential. We are now exploring options to clean our waste and produce chitin in one go… By using black soldier flies (BSF). As of today one of the many companies breeding BSF is hijauOrganik. Do check them out for more than just organic fertilisers. Do you think harvesting chitin here in Malaysia with BSF could help reduce waste? Leave a comment below on your thoughts about the subject and its potential.
