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Half of all food 'wasted' report claims


So reads the headline for a piece this week on the BBC website (BBC report on IMechE study). The study referred to, called Global Food – Waste not, want not, has just been published by the Institute of Mechanical Engineers. The headline figure relates to an estimate of food thrown away by consumers, but the report also quotes estimates of total wastage of harvested food at a similar level.

A key paragraph from the report’s summary reads:

Today, we produce about four billion metric tonnes of food per annum. Yet due to poor practices in harvesting, storage and transportation, as well as market and consumer wastage, it is estimated that 30–50% (or 1.2–2 billion tonnes) of all food produced never reaches a human stomach. Furthermore, this figure does not reflect the fact that large amounts of land, energy, fertilisers and water have also been lost in the production of foodstuffs which simply end up as waste. This level of wastage is a tragedy that cannot continue if we are to succeed in the challenge of sustainably meeting our future food demands.

On the face of it, this seems shocking, particularly when problems in developed countries include rejection of misshapen produce by growers and retailers and binning of food from people’s fridges because it has passed its ‘best before’ date. The situation in developing countries is rather different, with losses occurring largely at harvest and in storage.

 At a time when we are becoming more and more conscious of the need to use resources wisely (which is probably a more useful term than the ubiquitous ‘sustainable’), making sure that we minimise waste might be expected to be a priority, particularly in the industrialised world. The fact that the food chain does not operate as efficiently as it could may be seen as a tragedy, in the words of the report’s authors, but it is equally valid to consider this an overstatement of the consequences of a good supply situation. Taking this more optimistic view, the situation might be partly self regulating when the need arises.

First, I should say that avoiding waste would not solve the problem of 800 million or more people who are chronically undernourished. Although crop failures can be a localised problem, the majority of these people live in countries where there is in practice enough food available for them. However, it either cannot be distributed because of inadequate infrastructure (rural Africa, particularly in the rainy season) or they simply cannot afford it (large numbers of people in relatively prosperous India, particularly the urban poor).

What would help developing countries would be a big reduction in storage losses by storing food in dry conditions free from attack by rodents or insect. But this only applies to, for example, staple grains which are harvested and used as a food supply until the next harvest; most fruit and vegetables would be consumed quickly in any case. The main source of ‘waste’ for all crops is then losses in the fields. It takes as much effort and resources to raise a crop ravaged by insects as one which gets closer to its yield potential.

The situation in the rich world, on the other hand, is largely a consequence of a plentiful supply of affordable food. Given a choice, who would not buy undamaged, evenly-shaped produce? Some supermarkets, to give them their credit, do sell smaller than normal apples, for example, and second-grade ‘value’ fruit and vegetables in general. But there has to be a substantial price advantage to tempt people to buy them. Nevertheless, the report’s authors criticise retailers for rejecting “entire crops of perfectly edible fruit and vegetables at the farm because they do not meet exacting marketing standards for their physical characteristics, such as size and appearance”.

They even claim, somewhat dubiously, that up to 30% of the UK’s vegetable crop is never harvested because it fails to make the grade. Maybe, but we can assume that some of this reject crop is used for processing or animal feed or, if ploughed in, it increases the organic matter in the soil. It beggars belief that nearly a third of all vegetables grown are completely wasted. Further waste occurs because we choose only to eat parts of some crops. Leeks and cauliflowers are trimmed in the field, for example, the leaves of potatoes and other root vegetables are discarded and, in the home, many are peeled and have blemishes or bruises cut out. This can mean a significant part of the total weight is lost.

Certainly more food is thrown away than necessary because of many people’s blind observance of ‘best before’ dates, which are only set as a guide by manufacturers. But, since this is largely collected for recycling by local authorities, there is no reason why it should not be used either for composting or as a valuable source of fermentable carbohydrates to produce methane, other biofuels or indeed any other organic compound, using the appropriate microorganism or enzyme combination.

It is much more realistic to accept that such ‘waste’ will inevitably occur if food is plentiful, and concentrate on using discarded food as a resource. Attempts to legislate it away are doomed to failure. For example, the IMechE recommends that:

Governments in developed nations devise and implement policy that changes consumer expectations. These should discourage retailers from wasteful practices that lead to the rejection of food on the basis of cosmetic characteristics, and losses in the home due to excessive purchasing by consumers.

There will also doubtless be calls for more localisation and self-sufficiency. There is no need for this. The modern food chain is very good at getting food grown efficiently in one place and delivered in good condition to where there is a demand. We need to increase farmland productivity even further, and reduction of waste along the chain will certainly contribute to this. However, treating the current level of waste in the developed world as a tragedy is simply hyperbole.


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