Disturbing food waste trend ignites global call to action

Emerging economies must build waste minimisation thinking into supporting infrastructure and logistics around food production to cope with rising global demand for food supply.

Pressure is mounting on finite resources of land, energy and water used in crop harvest and manufacture, yet as much as 2 billion tonnes of the world’s food production is going to waste each year according to research released today by the Institution of Mechanical Engineers.

The wide-ranging study estimates that 30% to 50% (1.2 to 2 billion tonnes) of this food never reaches a human stomach.

In the UK alone, nearly a third of vegetable crops are not harvested due to their appearance, while up to half of all food bought in Europe and the US is thrown away by the consumer.

However these figures don’t reflect the fact some of the biggest losses are the embedded impacts of land, energy, fertiliser and water use during the production phase.

Here the report states that smarter strategies around water conservation and waste prevention could potentially provide 60 to 100% more food.

In less-developed countries, such as those of sub-Saharan Africa and South-East Asia, wastage tends to occur primarily at the farmer-producer end of the supply chain.

Inefficient harvesting, inadequate local transportation and poor infrastructure mean that produce is frequently handled inappropriately and stored under unsuitable farm site conditions.

Water conservation is one of the biggest issues with 550 billion cubic metres of water wasted globally each year in growing crops that never reach the consumer.

Depending on how food is produced, the demand for water in this supply chain could reach 10-13 trillion cubic metres annually by mid-century. This is 2.5 to 3.5 times greater than the total human use of fresh water today.

The study points to an urgent need for better irrigation techniques that can dramatically improve crop yield.

At the food processing stage, there is also a growing requirement for more effective washing techniques and management procedures. Recycling and purification of water could significantly reduce wastage here.

Meanwhile the global rise of the middle classes is fuelling rising demand for meat and animal-based production techniques, which will require greater land and resource use.

Considerable tensions are likely to emerge in the future, as the need for food competes with demands for ecosystem preservation and biomass production as a renewable energy source.

Energy, which is an essential resource across the entire food production cycle, also needs better management with estimates showing an average of 7-10 calories of input being required in the production of one calorie of food.

This varies dramatically depending on crop, from three calories for plant crops to 35 calories in the production of beef.

In modern industrialised agricultural processes – which developing nations are moving towards in order to increase future yields – energy usage in the making and application of agrochemicals such as fertilisers and pesticides now represents the single biggest component.

Wheat production takes 50% of its energy input for these two items alone. Indeed, on a global scale, fertiliser manufacturing consumes about 3% to 5% of the world’s annual natural gas supply.

With production anticipated to increase by 25% between now and 2030, sustainable energy sourcing will become an increasingly major issue.

Energy to power machinery, both on the farm and in the storage and processing facilities, together with the direct use of fuel in field mechanisation and produce transportation, adds to the energy total, which currently represents about 3.1% of annual global energy consumption.

Maxine Perella

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