By Bonnie McClafferty, Director of Agriculture and Nutrition, Global Alliance for Improved Nutrition (GAIN)
 
Post-harvest loss presents a formidable challenge. A recent report by the Food and Agriculture Organization of the United Nations (FAO) found that roughly one-third of the food produced in the world for human consumption - some 1.3 billion tons - is lost or wasted every year. Of particular concern is the loss of nutrition-dense produce - vegetables, fruits, fish, meat and dairy - some 50 percent of which goes to waste annually. Nearly half of those losses occur after the food has been harvested, resulting not just in lower incomes for small farmers but in higher prices for consumers, putting nutritious foods further out of their reach.
 
Unlike in the developed world, where most food waste occurs after purchase, most of the food loss in the developing world takes place at the front end of the value chain - a result of harvesting when ripe, and inadequate storage and cooling facilities. Because post-harvest also is key to maintaining nutrients, strengthening it improves health as well as economic outcomes. The challenge is that power for cooling often is too costly or simply unavailable. In sub-Saharan Africa, 70 percent of the population lives off the grid, while in India, some 350 million people lack access to electricity. The Institution for Mechanical Engineers in the UK estimates that if those regions were to adopt the same level of refrigeration as that of developed economies, one quarter of the total food wasted could be eliminated. While establishing a continuous chain of temperature-controlled environments from the point of harvest to the marketplace is, for many communities, out of the question, there are numerous low-tech fixes that can fill the breach. GAIN explored some of these in our latest Snapshot Report: Cultivating Nutritious Food Systems.
 
One such example is the Zero-Energy Cooling Chamber. Cheap and easy to build using just adobe bricks, sand and water, this sandbox-size contraption produces evaporative cooling chambers that can reduce the temperature of nutrient-dense vegetables and fruits by 15 to 20 degrees, extending their life by a couple of days. The CoolBot is another innovation being adopted by farmers. A small contraption produced by a US–based company, it works in tandem with a window air conditioner to transform a small shed or room into a reliable cooler. The device, which sells for about $300, can push the temperature in the room down about 32 degrees. Insulating the structure with hay bales or other materials enhances efficiency even further. A group of onion farmers in northern Tanzania tested the CoolBot with positive results. Instead of selling their onions right after harvest - and when everybody else was selling them - the farmers put theirs in a CoolBot-enhanced shed and waited two months. When they finally did bring them to the market, they made a handsome premium. Their profits were so high, in fact, they were able to pay off the CoolBot in a single season.
 
Should investing in post-harvest loss be a priority for action? Certainly, these efforts would benefit producers and consumers. Cold storage enables farmers to preserve their produce and also means that nutritious foods like dairy products, meats and fish can enjoy extended lives. But, success will depend on redoubling efforts to strengthen the supply chains that support the delivery of nutritious but perishable foods, most importantly in cooling and other aspects of the cold chain. It will also require us to look towards non-traditional partners, such as the cooling, transport and storage authorities. As with all efforts to build food and nutrition security, there is no single sector that can deliver the solutions. We must come out of our silos and work together to build markets for affordable, nutritious foods.