Food waste arises mainly because food has spoiled, oversupply and demands from markets, or individual consumer shopping or eating habits. The Food and Agricultural Organization (FAO) of the United Nations refers to food waste as food appropriate for human consumption being discarded, whether it is kept beyond its expiry date or left to spoil or not.
The term “wastage” encompasses both food loss and food waste. Further, FAO states that one third of all food produced in the world is lost or wasted from farm to fork. The wastage of food has enormous effects on the global economy and availability of food, besides its adverse environmental and social impacts.
Apart from natural disasters which can also play a significant role, the food losses are mainly caused due to inefficiencies in the food supply chains involving:
• Poor infrastructure and logistics
• Lack of technology, insufficient skills
• Management capacity of supply chain personnel and their knowledge
• Lack of access to markets.
Reducing Food Wastage
The basic concept of reducing food wastage involves four categories: reduce, reuse, recycle/recover and landfill. The first being most environmentally friendly and the last being the least.
The enormous amount of food loss is part of the global food waste and foodprint problem that the United Nations Environment Programme (UNEP) is intent on addressing through their current ‘Think, Eat, Save’ campaign. The Think.Eat.Save- Reduce Your Food Print campaign is in support of the SAVE FOOD Initiative to reduce food loss and waste along the entire chain of food production and consumption. The campaign encourages everyone, especially hotels, restaurants, supermarkets, and households, to change their habits and practices.
One of the best options for food waste management is to prevent food waste. However, a total prevention of food waste is difficult to achieve due to various reasons involving supply chain aspects of processing, preservation, transport and consumption.
Over the last decade, considerable efforts are being made globally to minimise the food wastage both at domestic and commercial levels. While prevention is the best strategy, it cannot be considered one and the only method for minimising the food waste. The conventional as well as many modern methods of treating the food waste are in practice today.
The most commonly used technologies include: landfill, composting and anaerobic digestion. While different food waste treatment technologies have emerged, their benefits and limitations are also clearly evident and require complex cradle to grave life cycle analysis.
Conventional landfilling requires dumping of food waste into open landfills but at the expense of environmental and social impacts. Organic waste deposited forms a perfect place to harbour micro-organisms that feed on the carbon and cause decomposition. Some disadvantages include:
• Landfills have anaerobic conditions that sets in growth of methane-producing bacteria resulting in release of greenhouse gases of methane and carbon dioxide.
• Methane emissions from landfill represent the largest source of greenhouse gas emissions from the waste sector.
• Landfill releases leachates into the soil and water ways in turn changing their quality
• Odour generated by release of hydrogen sulphide and ammonia causes distress to dwellers around the area and reduces the aesthetics of the property around the landfill.
It is not only the outdoor air which is affected by the release of landfill gasses from landfill soil, but the indoor air can as well accumulate the nasty gasses. The migration of landfill gasses from soil to buildings known as vapour intrusion can also occur through cracks, basement floors, and walls or floor drains. After entering the building, these landfill gasses can deposit on the indoor material surfaces. The adverse health effects of ammonia and hydrogen sulphide include coughing, irritation of the eyes, nose, and throat, headache, nausea, and breathing difficulties.
Landfill is considered as a last resort since it has adverse environmental, social, cultural heritage and economic impacts.
Composting of animal and human waste has been in practice since the Middle Ages, however it has gained more importance in recent years. The option to divert food waste from landfill for composting enables use of fertile soil for sustainable agricultural, benefits carbon sequestration and minimises the environmental impacts and landfill costs.
Composting is one of the most effective ways of reducing waste to landfills by transforming suitable waste into compost and biogas to enrich the soil health and fertility. Composting is a natural process of ‘rotting’ that decomposes organic matter such as residues, animal wastes and food garbage by microorganisms under controlled conditions.
There are also negative impacts on the environment associated with making and using compost depending on the technical approach used:
• Improperly maintained compost piles have a negative effect due to released gases
• When piles are not properly aerated, colonies of anaerobic bacteria flourish and produce methane and carbon dioxide known as greenhouse gases
• The decomposition also releases carbon dioxide, volatile chemicals, bacteria, and fungi
• The release of methane and carbon dioxide contributes to the problem of greenhouse gases in the atmosphere.
However, composting is economically viable and helps farmers improve the productivity of their soils and their income.
Recovering implies the production of energy and/or materials from waste e.g. through anaerobic digestion. This category comprises processing of wastage into nutrient like fertiliser and/or energy such as biogas. In anaerobic digestion, food waste is microbiologically broken down in enclosed containers in the near absence of oxygen.
Sending food waste to anaerobic digestion basically replaces conventional fossil fuel energy sources, so that the carbon savings are represented by the greenhouse gases that would have been emitted by generating the same amount of energy conventionally.
Economically speaking, anaerobic digestion is very expensive and needs subsidies and constant waste supply to be efficient however it is one of the best ways to divert waste from landfill.
The likely cause of food wastage in developing countries is due to agricultural production, post-harvest handling, and storage amounting to total of 44%. On the other hand, wastage occurs mostly during the production, processing, distribution and consumption phases constituting altogether 46%, in the developed world. In developed regions, around 300 million tonnes of food are wasted annually because producers, retailers and consumers discard food that is still fit for consumption. As per estimate of FAO 2013, about 20% of fruits and vegetables are wasted even before they leave the farm in Europe.
No matter how the food wastage occurs in which ever country, it significantly contributes to landfills, carbon emissions and ultimately climate change.
What can be done?
Many countries have come up with guidelines for preventing food wastage, its economic and environmental impacts. While it may not be simple, it will be most appropriate to take the responsibility and implement measures in our day to day life as an individual or community:
• Buy it with thought
• Cook it with care
• Serve just enough
• Save what will keep
• Eat what would spoil or distribute
• Eat home grown
A well-known quote by a famous personality, “Throwing away food is like stealing from the table of those who are poor and hungry”. It is further well quoted elsewhere, love and food are meant for sharing not for wasting.