Great haste makes (food) waste: hence, bioplastics comes into play.

Around 931 million tonnes of food goes to waste each year with 61% coming from households, 26% from food service and 13% from retail (World Economic forum). 17% of the food available for consumption in the world is wasted, a phenomenon that affects all countries beyond their wealth. In practice, 931 million tons in 2019 ended up in the waste bins of households, retailers, restaurants, and other food services, for a weight equivalent to that of 23 million fully-loaded 40-ton trucks. Globally, 121 kilograms of food are thrown away each year, with 74 kilograms at the household level – a waste that has extensive environmental, social, and economic impacts. Reducing them would lead to a cut in greenhouse gas emissions, slow down the destruction of nature through land conversion, increase the availability of food and therefore reduce hunger. Consumers today need substantial aid in order to reduce waste at home, particularly in the face of a situation that saw 690 million people affected by hunger in 2019 and is likely to increase due to the Covid health emergency. Hand-in-hand with this issue, a total of 3 billion people also cannot afford a healthy diet. Countries can raise the level of climate challenges by including food waste in national contributions to the Paris Agreement, strengthening food security and reducing costs for families (UNEP Food Waste Index Report 2021). From the table below it is possible to identify the  unequal distribution of food waste between countries if these are divided into separate income groups.

Delving deeper, it is additionally possible to see how food waste is distributed in Europe, specifically on a regional basis. As clearly visible, waste continues to have a positive correlation with the country’s income, as northern Europe is richer than the rest.

Old faces, new places: meet bioplastics

Food waste derives from all stages of the food supply chain. In the European Union  millions of tons of food waste are generated every year, a large part of which derives from the food sector (RSCPublishing). Thus, converting it into value-added chemicals can be a great asset in the achievement of sustainability. A very valid solution is represented by bioplastics. These can be defined as “not just one single material. They comprise a whole family of materials with different properties and applications. […] a plastic material is defined as a bioplastic if it is either biobased, biodegradable, or features both properties” (European-Bioplastic). It can be therefore said that bioplastic is a plastic material derived from renewable or biodegradable sources. The decomposition time of bioplastic varies greatly depending on the starting materials and the composting conditions. In humid environments such as special composters, bioplastic can biodegrade within a few months, however, in dry environments and with the appropriate treatments, bioplastics can ensure excellent sealing (Riccardo spaccini et al). In the figure below, bioplastics are represented based on their biodegradability or bio-based content.

There are many types of bioplastics on the market. Some examples of bioplastics are those obtained from food crops such as corn starch, wheat, tapioca, potatoes; biodegradable bioplastics for industrial plastic applications (API); poly bioplastics, obtained from sugars; PHA polyhydroxyalkanoates and derivatives: polyhydroxy butyrate, polyhydroxy valerate, polyhydroxy hexanoate; cellulose-based bioplastics as bigrade. The means of possible application of bioplastics is endless; just like the less ethical little sister – derived from petroleum, the classic plastics – bioplastics have captured the attention of various industries – from the agricultural sector to the automotive. 

The advantages of bioplastic use are evident: first and foremost, it is biodegradable, meaning that microorganisms present in the environment come in touch with the bioplastics, breaking it down completely into water, carbon dioxide and compost (Renee Cho). This phenomenon causes a decrease in waste headed to landfills or incinerators, usual destinations for traditional plastic waste, and a decrease in the release of harmful substances into the environment. Plus, it requires significantly smaller amount of energy to be manufactured. Last but not least, a fewer amount of toxic substances is disposed of into the environment after the plastics is broken down (Jane Goodall). A portion of the biodegradable bioplastics is compostable. In this case, waste management costs are substantially reduced, especially in the agri-food industry. Bioplastics result to be particularly hygienic, making them perfect for use as food packaging materials or containers for perishables for home use. In the case of incineration, less toxic fumes are emitted (Abe et al).

Not all that glitters is gold

However, some difficulties persist. Contrary to what can be thought, bioplastics cannot be discarded everywhere, and total (bio) degradation is not always ensured. This applies to a wide array of bioplastic types. The main problem, therefore, concerns the disposal of these. Firstly, degradable and compostable bioplastics must not be disposed of together, as this would otherwise alter the degradation process (Arda et al). If this happens, there is a high probability that methane will be produced, a greenhouse gas that is far more toxic than carbon dioxide. In terms of disposal, compostable plastics can be contaminants in a batch of recycling, which can cause issues with proper recycling and eventually cause an increase in landfill waste (Celeste Robinson).

A further problem is the environmental impact that bioplastics have on the environment when they are produced. Through a Life Cycle Management Analysis, it is possible to determine the impact that all the processes produced have on the environment (Iyyanki V. Muralikrishna, Valli Manickam). This analysis concerns both the raw materials used and the aforementioned disposal process. This analysis turns out to be very important since we the major focus is often placed only on the carbon footprint of these specific materials. If PLA production is taken into consideration, for example, it is necessary to use corn or maize for its production process. In some countries, the extensive use of this type of raw material becomes damaging to the resulting food use (Carus M., Dammer L.). These two materials are utilized mainly because “most green plants produce this polysaccharide as an energy store. Human diets also consist of this carbohydrate, and it is contained in enormous volumes in primary foods, including rice, cassava, maize (corn), wheat, and potatoes. Among them, the most important starch is cassava starch, which contains more than 80% starch in dry mass. Starch is a carbohydrate that contains a great number of glucose units, combined through glycosidic links (M. K. Marichelvam et al.)”.

It seems now fair to assume that bioplastics (with their due limits) can guarantee a circular alternative in the field of food waste. The most common practice is to use a part of these to create biodegradable or compostable packages, which are capable of significantly reducing the environmental impact and food waste itself. The question therefore directly arises around how this transformation occurs. To this end, there are various methods which differ both in nature and in mechanism. For a  general overview, it can be said that the main methods are carried out through:

– Mechanical and thermal conversion of food waste to fermentable organic compounds (Pagliaccia et al)

– Chemical conversion of food waste to fermentable sugars (Mussoline et al)

– Biological conversion of food waste to fermentable substrates (Vasmara et al)

– Enzymatic hydrolysis of food waste (Kiran et al)

– Bioconversion of fermentable substrates from food waste to bioplastics (Takahashi et al)

– Physic/chemical modification of bioplastics (Tommonaro et al)

– Fermentation technology (Sandhya et al) 

– Cellulose-based bioplastics via physic/chemical modification (Rinaudo)

– Chitin-based biopolymers via physic/chemical modification (Ravi et al)

– Caprolactone-based bioplastics via physic/chemical modification (Poli et al)

These represent only some of the main ways to obtain bioplastics, which makes this practice particularly effective in terms of circularity.

Another ace in the hole: bio-lubricants

A different use that can be made of food waste is the creation of natural lubricants from animal or vegetable elements. The former derives from the remains of pork, sheep, or cow fat, the latter from sunflowers, soybean, rape, seed, castor, cotton, etc. These are used to create intermediate materials (oleic acid, acelain acid, glycerine, etc.) and then create basic natural oils. These lubricants are then used in agricultural or industrial fields (Ioan I. Ştefănescu et al). One of the reasons why this practice is considered highly circular is because its ecological footprint is quite high at every stage of production, usage, and disposal. “The main purposes of lubrication are (i) to reduce wear and prevent heat loss that results due to contact of surfaces in motion, (ii) to protect it from corrosion and reduce oxidation; (iii) to act as an insulator in transformer applications; and (iv) to act as a sealing agent against dirt, dust, and water. While wear and heat cannot be eliminated, they can be reduced to negligible or acceptable levels by the use of lubricants”(Leila Naderloo et al).

The use of bio-lubricants not only significantly reduces the impact they have, compared to their similar chemical nature, but they have as their best advantage an increase in performance at a lower cost. This is due to their chemical composition given by the presence of a polar group with a hydrocarbon chain, which can guarantee more advantageous properties: low viscosity, high ignition temperature, increased equipment service life, high load-carrying abilities, low volatility, high flash point, and high oxidative stability. In addition, the materials which they produce are non-toxic, cost-effective, and biodegradable (Dharma R. Kodali). Bio lubricants represent the ideal solution for the toxic externalities deriving from petroleum-based lubricants because of the low emissions to the atmosphere produced and rapid biodegradability. For industries, it will represent a great asset in the reduction of costs while increasing quality and creating a safer environment (Ajith Kumar). An example of the application of biolubricants is provided by the Frontsh1p project. Among the many objective ambitions that this sets itself, it emerges that of obtaining “Oil crops in marginal lands in Lodzkie Region towards lubricants and animal feed”. 

Novamont is one of the leaders in the production of bio-lubricating bioplastics for the creation of a future less dependent on petroleum derivatives. In the framework of the FrontSh1p project, Novamont cooperates with the Lodzkie region (Poland) and brings its expertise to the farmers of that area. The aim is “to establish innovative oil crops genotypes (rapeseed, milk thistles) adapted to local pedoclimatic conditions and in full respect of regional biodiversity in identified marginal lands to obtain low impact biodegradable lubricants and animal feed while revitalizing soil quality and maximizing economic opportunities for farmers “(FrontSh1p). The purpose of this project is the creation of vegetable oils and proteic oil meals. The first one will be reprocessed by Novamont for the formulation of innovative low-impact biodegradable biolubricants. The second one will be used to feed animals, substituting (partially) conventional diets, without utilizing imported materials (usual soybean) from outside Europe. This project is just an example of how the processing of vegetable and animal waste can create circular solutions capable of developing the economy, improving the quality of work, and reducing the environmental impact.

What do we hold for the future?

As it is well known, to combat environmental problems and change the structure of the consumption models of modern human society, mainly political responses are needed.  A striking example is precisely food waste. Today we live in the richest period and with generally more widespread welfare, in all of human history. This very high level of well-being, combined with a consumer lifestyle, has brought the phenomenon of food waste to an all-time high. Technology can in fact represent a multiplying factor of the speed at which certain objectives can be achieved, but not the main solution. The introduction of plastics and the processing of plastic derivatives, for example,  led us into the future, helping human beings to reach new goals in the scientific field, as well as improving our daily way of life (OECD). However, since it has since been discovered that this is beginning to be one of the main causes of pollution on the planet, it has been necessary to veer towards new horizons. Bioplastics, on the other hand, already have much fewer negative implications from the beginning (which, as discussed, are not non-existent), and many more positive sides. They certainly represent a much more circular solution, both in economic and environmental terms, given that everything can be reused. However, to achieve a sustainable economy, these represent only one piece (however large and important) in the great puzzle of today’s society. When it comes to sustainability and circularity, the theme of transition to one or the other must always be introduced. A world without plastics tomorrow is currently hard to imagine. At the same time, imagining a world in which only bioplastics are used is also a scenario that is difficult to picture. As the Latins would say “in medio stat virtus” (virtue is in the middle), meaning that a progressive reduction in the production and use of plastics, together with the management of its disposal and recycling, must be implemented in parallel to an increasing introduction of bio compostable and biodegradable solutions. Transferred to the policy level, this means that the states will have to apply policies capable of guaranteeing a linear and gradual (but not slow) transition towards a completely circular situation, influencing the behaviors and choices of all the actors involved (from large multinationals, up to the small local consumers). 

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