|Page: Insects may be the answer|
Grub's up: fried crickets for lunch. Photograph: KHAM/REUTERS
As with gingerbread men and gummy bears, the dilemma when served a locust is whether to begin eating it head or legs first. I choose to start with the six little legs (sometimes you need to fold them in a bit because they tend to trail out of your mouth otherwise), then the abdomen and finally (gulp) the head. Crunch, crunch, swallow. Think: bbq prawns, but unshelled.
I'll be honest, deep-fried locust is not the most delicious snack I've ever had. But on a long road trip through Cambodia, it was cheap, filling and tasty enough – more than can be said for most motorway service station food in Britain and less frightening than other menu options in the region. Goat-scrotum hotpot, anyone?
In south-east Asia, insects are an important part of the daily diet for millions of people. Crickets, cockroaches and other bugs and grubs are sold across the region by roadside vendors and in smart restaurants. They are harvested commercially and by home producers, providing vital income for struggling farmers. Often, insects are the only source of income for women earners, who rig polythene awnings above a fluorescent tube-light to trap flying insects after dark.
Insects are plentiful, multiply and grow to adulthood rapidly and require little food to sustain them. They are the perfect source of protein. As countries in the west and developing world wake up to the looming threat of food shortages, it's time that governments seriously considered an alternative source of protein. Could insects provide food security for the coming centuries?
Entomophagy (insect eating) is a growing industry with more than 1,400 insect species being gobbled in 90 countries. In terms of how much food insects require per gram of protein produced, they are twice as efficient as chickens and more than six times as efficient as cows. One reason for this is that insects are cold-blooded, so they don't need to eat food to keep warm.
Animal feed is an important consideration as agricultural costs soaring across the world, leaving millions of families unable to meet their basic rice needs. Meat is an unheard of luxury for many in the developing world, leading to protein deficiencies for populations across sub-Saharan Africa, south Asia and Latin America.
The nutritional benefits of insects and better ways of marketing them were probed during an international conference last year in Chiang Mai, Thailand, involving scientists from 15 different countries, but not enough progress has been made since then. Researchers, governments and international agencies such as the UN Food and Agriculture Organization need to look seriously at insect harvest and production to meet the world's food needs both in the poor world and the rich west. This doesn't necessarily mean a cockroach burger with grub fries, but it could mean using insect protein to replace soya bean protein in packaged foods. Insects are a far more environmentally sustainable source of protein, because they can be harvested without destruction of forests or food crops.
It's not the perfect food. People allergic to some seafood are likely also to suffer insect allergies. And insects exposed to pesticides retain high levels of toxins in their bodies.
There is a niche market for insects; there are cookbooks, websites, online recipe sites, suppliers and restaurants specialising in bug dishes. But insects need to follow the path of other exotic foods, such as sushi in the 1990s, and become desirable. As entomologist Gene DeFoliart, at UW-Madison, says: "If insects become more widely accepted as a respectable food item in the industrialised countries, the implications are obvious. They would form a whole new class of foods made to order for low-input small-business and small-farm production. International trade in edible insects would almost certainly increase."
Still grossed out by the yuck factor? It's worth realising that most of us do already eat insects. The US Food and Drug Administration allows, for example, up to 75 pieces of insect in 55mm of hot chocolate and up to 60 aphids in a portion of frozen broccoli.
• Gaia Vince is travelling around the developing world looking at the impacts of climate change