A few pounds of damaged fruit here, a couple of uneaten sides left behind at a restaurant there. It may not seem like much, but it adds up. In fact, it amounts to nearly one billion tons of wasted food per year globally according to the United Nations Environment Program.
The situation is particularly dire in the United States, where food waste comprises 22% of municipal solid waste—the most of any one kind of item. Once in landfill, food produces the potent and harmful greenhouse gas methane. In fact, food waste alone is estimated to account for around 8% of human-related greenhouse gas emissions globally, even more than the airline industry.
Beyond the negative environmental impact of food waste, there is also the fact that uneaten and inedible food are still viable resources that could be effectively utilized. This is beginning to change as new technologies are being developed that both mitigate the harmful effects and maximize the utility of food waste. Here we look at some of the innovations being used to give food waste new life around the world.
Biogas through anaerobic digestion
Creating biofuel from biological waste material is an efficient way for local municipalities and facilities of any scale to handle both mixed food waste and leftover fats, oils, and grease. With anaerobic digestion technology, biological waste material is fed into a tank where it is digested by acidogenic bacteria and other anaerobic microorganisms, which in turn produce methane and carbon dioxide. These gases are captured and either used as fuel directly or processed into biomethane.
Producing energy this way has a much smaller carbon footprint than fossil fuels or biogas produced from purpose-grown crops, and leftover digestate at the end of the process can be used as nutrient-rich fertilizer. Anaerobic digestion technology is used throughout the world, and according to the United States Environmental Protection Agency, there are over 200 facilities processing food waste into biogas in the US, using mainly industrial and food service waste. In the United Kingdom there is even a cheese factory that has partnered with a local biogas facility, supplying leftover whey that produces enough energy to heat 800 homes per year.
Closed-loop commercial composting
The concept of a closed-loop system—where food waste is composted and the resulting soil used to grow new food—is not a new one, but the development of small-scale commercial composters has made it possible for facilities of any size to integrate this system into their operations. This means food waste has less distance to travel before being turned into a useful material, significantly cutting the logistics emissions involved.
Commercial composting machines typically work with aerobic decomposition. Food waste is added to the device, where it is automatically mixed with a base material containingheat-resistant microbes. The contents are brought to a high temperature and constantly agitated to speed up the process and prevent the production of methane. The process is highly efficient, and soil is ready for use in just 24 hours.
Such composting devices are being used everywhere, from world-famous restaurants to public universities, in closed-loop systems where compost is used to grow food once again. This simple piece of tech is helping locavores eat truly local produce that is produced directly from food waste.
Giving food waste a new life as products
Rather than finding a beneficial end of life for food waste, other companies and public-private collaborations are innovating ways to give it a second life as completely new materials—like plastic.
For example, Scottish biotech startup CuanTec has developed a more eco-friendly process for extracting the sugar molecule chitin from seafood waste, which it uses to produce compostable bioplastic. The European Union’s Barbara Project is also developing ways to integrate compounds derived from food waste and agricultural by-products into robust bioplastics suitable for use in the automotive and construction industries.
Food waste is also revolutionizing the textile industry, driven by an increased demand for sustainable and plant-based materials. While vegan “leather” made from plants like mushrooms has been around for a while, innovations in materials science like Agraloop are making it easier to produce textile-suitable fibers with waste from agricultural crops.
New technologies on the horizon
Beyond these developments, there are many still-experimental technologies that have the potential to further transform how we utilize food waste. Recently, research at Virginia Tech on using waste from the beer- and wine-making processes to improve water quality has been promising, while in the European Union, a new biomaterial that can be used as a wound dressing that accelerates healing is being developed from eggshell waste.
Many technologies are also working to tackle food waste from another angle, by trying to prevent it before it occurs. For example, Apeel Science has developed a plant-based coating that can be applied to fruits and vegetables to give them a longer shelf life. Imagine the possibilities: In the future, coatings such as these could even be created with food waste itself.
It’s exciting to see all the scientific and technological developments that are brewing in the fight against food waste. Yet despite these innovations, managing food waste is still an enormous struggle throughout the world. There needs to be further improvements in infrastructure, and increased awareness about both the negative environmental impact of food waste, and that it is indeed a valuable resource that can be given a second life through the power of science.
About the author:
Shannon Bergstrom is a LEED Green Associate, TRUE waste advisor. She currently works at RTS, a tech-driven waste and recycling management company, as a sustainability operations manager. Shannon consults with clients across industries on sustainable waste practices.