Inside an eight-metre long garden shed behind their suburban house in ealing, tiziana di costanzo and her husband, tom mohan, run horizon insects, the only farm in london growing insects for human consumption. on eight sets of wooden shelves and in several large plastic boxes, the couple are breeding more than half a million mealworms and crickets for people to cook and eat.

You can put them in stir fry, you can use them in protein balls, you can make tagliatelle, dicostanzo says. if you pour ground crickets into pizza dough, you get a good proper full meal...they are as nutritious as fish but without depleting the oceans.

The couple started breeding insects in 2013 after their son embarked on farming them for an extracurricular project; today they sell bugs fresh and dried and run cookery classes. clients have included vets, students, researchers from congo and a chef from a yacht in the caribbean. dicostanzos insects have also graced dishes at theritz.

Fresh mealworms taste like a chicken-meat hybrid, she says, and make a good base for rag, while the dried ones are nuttier. the dried crickets i add later to my bruschetta taste a bit like pumpkin seeds with a hint of bacon.

Bug-growing is becoming big business. the worldwide market for edible insects was worth $112m in 2019 and is projected to reach more than $1.5bn by 2026, according to global market insights.

As consumers become aware of the damage that intensive meat production and fiendishly complex supply chains are doing to the environment, researchers and producers hope that entomophagy the technical term for eating insects can provide some answers.

There are about 2,000 known edible insect species, although estimates vary, and the history of eating them goes back thousands of years. pliny the elder mentions beetle larvae as a first-century snack and insects are still a delicacy in many parts of the world.

In thailand, ant eggs are boiled in coconut milk as a dessert known as tom kati kai mod daeng, while in uganda grasshoppers are eaten fried with onions. in sardinia, the prized casu marzu literally putrid cheese contains maggots.

While data on insects nutritional value is limited at present and varies a lot by species, the british nutrition foundation says they may be a good source of healthy unsaturated fats and that some species have a higher iron content than beef.

Chef thomasina miers says she first discovered the deliciously nutty, earthy flavour of insects 25 years ago in mexico when she was presented with a tortilla filled with roast worms.

As co-founder of the mid-market mexican restaurant chain wahaca, she was among the earliest to put bugs on a mainstream british menu by offering cricket-flour brownies and pured grasshoppers in salsa.

Whenever we have had them on the menu, we have had a really positive response, she says. she ended up removing them because the supply costs were too expensive at the time and she was not sure if the cricket flavour overwhelmed the brownies.

Not everyone is convinced insect brownies will become mainstream. simon stenning, an independent consultant to several restaurant chains, says its a no-brainer. we need to be using insects more in a strategic way but adds that as human food they remain a gimmick. the people that go to eat at a hungry horse [pub] are not going to be eating insects as their sunday lunch, he says. nevertheless, there are compelling environmental reasons to hope insect-eating catches on.

The greenhouse gases produced in farming 1kg of chicken protein are 300 times those of 1kg of bug protein, according to edible insect producer eat grub. for one kilo of beef, the multiple is 2,850 times. insects also consume significantly less water. in fact, barely any at all.

Insects have been talked about for quite a long time but now it seems to be getting a head of steam, says professor simon mackenzie, deputy head of the university of stirlings aquaculture department, who is researching the potential of insects as food for fish.

Mackenzies project is being supported by 10m from government agency innovate uk. its the countrys first properly funded insect platform, he says. in the eu, eight types of insects are being reviewed by the european food safety authority with approval for their use as food for humans expected from the european commission by the endof the year. on the list are blacksoldier flies, mealworms and house crickets.

Christophe derrien, secretary-general of the international platform of insects for food and feed (ipiff), a trade body, says the next three to five years will be a turning point. nine million europeans tried eating insect products in 2019, ipiff data suggests, a number it forecasts will rise sharply by 2030. the biggest companies in the market still small by industrial agriculture standards are ramping up.

And technologies are becoming more sophisticated. these include modules for housing insects that have high levels of automated control insects tend to be very specific about the temperatures they prefer. insect producer better origins x1 mini-farm unit uses ai to clean and convert waste from chickens into insect feed and to monitor the health of insects through their lifecycle before processing those bugs to go back into chicken feed.

The main issue for us is now about scaling up those technologies and ensuring that producers can produce at sufficiently high levels to respond to demand, says derrien, adding that he likes to eat roasted insects with an aperitif.

For researchers, among the most appealing aspects of insect farming is that the critters eat waste. the un estimates that about a third of food destined for human consumption globally goes in thebin. this makes insects an elegant sustainability story, mackenzie says.

And they dont just eat food waste. in a small plastic box in the horizon insects shed, dicostanzo is testing a diet of kebab shop cardboard takeaway cartons onmealworm larvae with notablesuccess.

According to neil whippey, co-founder of eat grub, insects are perfect for intensive farming: crickets, for example, when they are reared, naturally like small enclosed dark spaces. its not like battery-farming cattle, which is not something that wants to be enclosed in a small area.

Insects can be grown in vertical stacks of containers up to four metres high, according to insect farming company entocycle, which uses an automated system to minutely control the atmospherics of the bugs environment. their excrement is useful too. frass, as it is known, can be used as a fertiliser.

Animal rights campaigners have raised concerns, most focusing on whether insects are sentient beings. the ipiff requests that its members commit to a set of welfare standards and multiple studies are under way to establish whether invertebrates feel pain in the same way that vertebrates do.

While it might take consumers a while to get their heads around the idea of swallowing grasshopper legs, stenning and others say that insects have even greater potential as animal feed.

Larger consumer companies have already shown an interest. nandos, the chicken restaurant chain, said last month that it was funding research into insects and algae as chicken feed in order to reduce its reliance on soy, the second biggest contributor to global deforestation after beef.

Keiran whitaker, entocycles chief executive, describes this as catering to the transition period. i built entocycle to feed humans, he says. but a certain view in the western world about eating insects means entocycle has for now focused on feeding animals instead.

Both entocycle and rival insect farming company better origin use black soldier fly larvae, which miha pipan, better origins co-founder, describes as the pig of the insect industry. like pigs, they will eat anything and they have a very fast growth cycle, he says.

Derrien says getting insects into animal feed is the ipiffs major focus. this is thanks to growing concerns about europes lack of food security, which risks price swings and shortages, not to mention viruses reaching animals and humans from imported food. according to european commission estimates, more than 90 per cent of the eus soy supply is imported.

Mackenzie says feeding insects, rather than soy or corn, to fish is likely to improve the fishs health and welfare because an insect-based feed would be closer to their natural diet. the same goes for chickens. but there are nutritional benefits for humans too.

Several studies have found that insects have a positive effect on the human immune system, while whippey, who suffers from crohns disease, an autoimmune bowel condition, claims that bugs nutritional complexity and high protein levels have been crucial to his diet.

We just need to change our view of them, says miers. my attitude now is that they are just like shrimp or cockles. they are just land molluscs rather than sea molluscs so i dont see them in that yucky way. although, she admits, if i was faced with a spider i might.

Alice hancock is the fts leisureindustries reporter

Follow on twitter to find out about our latest stories first.