January 11, 2013, by Fraser

Food waste is not an absolute concept

Dr John Strak, Honorary Professor in Food Economics at The University of Nottingham, wades in on recent reports regarding food wastage in the UK and the claim that we throw away half of our food. 

The Institute of Mechanical Engineers (IME) has hit the headlines this week with its report on waste in the global food system. The report makes some bold assertions and estimates that, because of  poor practices in  harvesting, storage and transportation, as well as market and consumer wastage, 30–50% (or 1.2–2 billion tonnes) of all food is wasted. That’s  a bold claim and I am not going to question the mathematics here. (But I do note that the supermarkets in the UK have refuted the IME’s claim that supermarket promotions and a reluctance to stock produce that is not visually attractive, are part of this waste problem).

Whatever the level of waste it seems commonsense to believe that reducing “waste” is part of the set of solutions for achieving global food security.  Indeed, at the University’s recent food security forum in Shanghai recently, two of the speakers highlighted the waste issue.  Dr Yuelai Lu from the UK-China Sustainable Agriculture Innovation Network (SAIN) noted that one of the key actions needed for food security was to “reduce waste” and Professor Lin Erda from the Commission on Sustainable Agriculture and Climate Change detailed a key recommendation of the Commission to, “reduce loss and waste in food systems, targeting infrastructure, farming practices, processing, distribution and household habits”.

But what is “waste”?

In my experience of the agri-food chain, and with my professional economics hat on, I can only say that “waste” is what we do not value and it is a concept that requires some care in our discussions. And, mostly, the marketplace ensures that valuations give us good guidance on what is, or is not, wasteful.

A few examples  will help us understand how the definition of waste changes according to market conditions. If you are ever lucky enough to visit the Caribbean or any sub-tropical climate you cannot fail to notice the amount of tropical fruit that lies rotting by the roadside. This fruit is waste because the cost of storing it or transforming it into a nutritious food product is very high, and by the fact that there are plentiful supplies of fresh fruit to replace any fruit that is not eaten in prime condition.

We can always reduce waste by a technical process but if the cost of doing so means that we cannot use financial resources to, say, improve sewage provision, supplies of clean water or access to medicines we have not helped anyone by reducing food  waste. On the other hand, a fresh produce producer in East Anglia in the UK will know that the costs of removing the waste green matter or rejected vegetables from his production site to a landfill destination will be very high and so will attempt to reduce his “waste” or transform it into another use e.g. compost or biomass for energy production. In the East Anglian situation the comparison of costs and alternative uses of finance is quite different than for the sub-tropical region.

The marketplace

But in both cases the marketplace guides our view of what is waste and what the appropriate amount of effort should be to reduce waste. It is not as simple as saying, all food waste is bad. Crucially, “food waste” is not an absolute concept – it must be considered relative to all the actions and resources available in the food system.

The IME report recommended that more technical know-how should be transferred to developing countries to help reduce waste and that Government policy should be proactive and try to change consumer expectations and retailers’ “wasteful practices”. Unfortunately, the IME missed out on one important recommendation that would have driven these know-how transfers and consumer preferences more efficiently than any government policy or technical aid programme. We need the market to operate in the agri-food system and only then can we be sure that “food waste” will be at an optimal level – where resources are allocated to production (and waste reduction) in the correct manner.


Posted in food waste