Impact and knowledge
Currently the world produces a lot more food than needed. A lot of food never gets eaten and ends up in the waste bin instead. Food waste happens everywhere: on farms, during transport, in warehouses, in supermarkets, fast food restaurants, in canteens of various institutions such as schools, hospitals and companies, and in households. Food waste occurs in most places where food is produced or consumed.
Why is food waste a problem?
Food waste represents a double burden for the environment:
- Food embodies natural resources including land, soil, water, seed, fertilisers, herbicides and pesticides. It also embodies the work of many people who produce and distribute food. Producing the food also uses chemical inputs and energy mostly generated from non-renewable fossil fuel-based resources. All of this goes to waste when food does.
- The collection, transportation and disposal of food waste also requires energy and water and creates further emissions, including methane emissions from food waste rotting in landfills.
Food production creates secondary waste streams, such as packaging materials, plastic waste on farms, emission from energy generation, cold storage and transportation, and chemical run-off from agricultural land into rivers and coastal waters endangering natural ecosystems such as Australia’s Great Barrier Reef, which faces great environmental pressures from coastal development. Processed food adds additional sources of waste such as plastic and metal packaging, byproducts of artificial ingredients and the energy from processing.
As a consequence, food waste has become one of the largest contributors to climate change! The systems of production and consumption of food are the second largest sector contributing to climate change, accounting for 18-30 per cent of global greenhouse gas emissions (GHGe). Food waste represents at least one third of these emissions, and is estimated to generate 8-10 per cent of global GHGe, which makes it a larger contributor to climate change than the global steel industry or most individual countries in the world. About 25 per cent of global fresh water resources are used up in food waste.
Food waste is also a significant social problem as high levels of food waste are associated with high levels of diet-related non-communicable diseases. Research has shown that high levels of food waste correspond with overconsumption, obesity, diabetes and malnutrition.
Food waste is part of a flawed food system that provides for a world in which 800 million people have little or very low access to adequate food, where more than 2 billion people are considered overweight; and where one third of food is thrown away. Food waste coexists with poverty, malnutrition and hunger and, as such, poses a deep ethical challenge for societies. Food waste is not simply an indicator of production and consumption efficiency, it is considered in research as a symptom of an unhealthy food system.
How much food waste do we have in Australia?
The Australian government announced a national food waste strategy in 2017, inspired by the UN Sustainable Development Goal 12.3 to halve food waste by 2030. The National Food Waste Strategy attempted to understand the current status of food waste in Australia and to define strategic priorities on how to address food waste along the whole food chain.
The National Food Waste Baseline published in 2019 indicates that Australia is among the world’s largest creators of food waste on a per capita basis. Similar to many developed economies, food waste here is mostly considered a problem of the production stage and individual households.
What is food waste?
The National Food Waste Strategy has provided a definition of food waste in the Australian context, which covers:
- solid or liquid food that is intended for human consumption and is generated across the entire supply and consumption chain;
- food that does not reach the consumer, or reaches the consumer but is thrown away. This includes edible food, the parts of food that can be consumed but are disposed of, and inedible food, the parts of food that are not consumed because they are either unable to be consumed or are considered undesirable (such as seeds, bones, coffee grounds, skins or peels);
- food that is imported into, and disposed of, in Australia; or
- food that is produced or manufactured for export, but does not leave Australia.
What are our priorities to manage food waste?
Similar to other countries, Australia has defined industry and policy priorities for addressing food waste by publishing its own version of a food waste hierarchy.
According to this hierarchy, the highest priority is prevention, followed by options to redistribute food to people in need and to re-use surplus food to produce animal feed. Other options include composting, nutrient extraction, incineration and disposal to landfill, the least desirable yet most prevalent option presently used in food waste management. The waste hierarchy is not a definite list of instructions, but is designed as a framework supporting the evaluation of different food waste management options within specific contexts.
How to collect and manage food waste?
The circular economy principles require a re-design of current production and consumption to avoid waste before it occurs – a principle called designing waste out of production processes. However, before such a re-design can be successfully implemented and established, and food waste reduced and prevented, the need to manage existing amounts of food waste will be one of the highest short-term priorities. Accordingly, another principle of circular food economy calls for re-using and recycling food waste to prevent it from entering landfill.
At the level of our community one important way to achieve this is to set up a system to separate food waste and turn it into fresh soil through a composting process. A key purpose of this website is to help communities to set up a working food waste recycling and composting process. Initially, this means to set up a waste collection and management system. As a next step, this website provides resources that support communities in using the compost to grow their own food.
A critical first step is to assess different sources of food waste within your community. In the case example used for this website, Yarrabilba State Secondary College, the following common sources of food waste were considered:
- waste bins on site;
- canteen and tuckshop;
- home economics and food studies classroom;
- food outlets in immediate neighbourhood; and
- food waste brought in from home.
Before deciding which waste streams to include in our community circular food economy system, it was critical to evaluate the present status by considering the following factors:
- number and location of collection bins;
- frequency of collection;
- composition of waste in different bins;
- amount of waste collected within a period of time (day, week);
- food waste-to-compost calculator;
- required space and suitable location to process waste;
- required equipment; and
- other resources.
Waste bins
Depending on the expected amount of waste collected, different bins can suit the purpose. The most important success factors for establishing a composting process is to separate organic waste from other wastes and to process organic waste as early as possible.
The strict separation of waste is esssential as contaminated organic waste restricts its usefulness after the composting process has been completed. To achieve strict separation of waste it will be necessary to:
- provide separate bins for organic wastes;
- provide clear instructions what is allowed to go into the organic bins; and
- provide instructions and collection bins for other types of waste such as general landfill waste and recyclables.
It is useful and quite easy to track the waste volumes over time. For example, once organic separation starts, the waste amount in the general landfill bin should reduce quite rapidly, which may also result in a potentially significant reduction in waste disposal fees for organisations.
The best way of separating waste is not to mix it up in the first place. Waste separation can otherwise turn into a difficult and unpleasant task. The principles for separation are described in the Compost section and can also be found on the Composting App or many different websites that offer resources for composting.
Processing waste early is important as the objective is to achieve a healthy composting process. Food waste left unattended and untreated will start to rot and create an unhealthy environment. The main difference lies in the balance of different materials used and the process of decomposition. Composting, as further described on the next page, creates specific conditions and a mix of specific materials to ensure food breaks down into healthy soil, while rotting is an unhealthy decomposition process caused by bacteria which creates pathogens and foul odours.
Composting location
Based on the following factors, a suitable waste processing and composting area within the community can be identified and selected:
- expected amount of waste created for composting on site;
- collection frequency and times;
- staff or volunteer availability; and
- method of composting and further use of end product.
Activities
Learn about waste and hands-on waste sorting
Objective: Understand about different waste types and appropriate separation and disposal; hands-on practical activity.
This activity is designed to give students an idea of waste composition and an understanding of how mixing waste creates an unmanageable mess. The images below show a sample activity from the Yarrabilba State Secondary College. The students learned about different waste types and then proceeded to dump the contents of a waste bin on a trap. The next step was to separate the waste into different piles:
- Compostable – green
- Compostable – brown
- Soft plastic
- Recyclable plastic
- Containers for change
During the sorting process, questions on different waste items can be discussed and addressed. The exercise will also create an understanding of the need for separate waste bins for different types of waste and how to make a set of instructions to guide waste disposal on school grounds.
Workshop to design a waste collection and composting system
- Use information from exercises, such as the waste separation activity, as a guide to discuss and design a circular economy system for your community or school.
- Discuss existing food and waste flows through the community and school and identify reasons for waste creation.
- Split into working groups to list solutions to the problem of waste creation and design different systems to reduce and eliminate food waste.
- Present solutions, discuss and debate the benefits and shortcomings of each solution.