A powdered mix made of crushed fruit, seeds and nuts is poured into a flask, cold water is added, it’s given a shake and out comes a thick, greeny brown sludge. Ambronite – from ambrosia, the word for the food of the gods in Greek mythology – is just one of a number of products being sold by companies that claim drinkable meals are more efficient and sustainable than traditional meals.

“The future of food must be one that both takes our planet into account and serves humans better,” says Simo Suoheimo, co-founder of Finnish startup Ambronite, based in California. “We believe food as a system is broken and ripe for disruption. Up to 40% of food in the US is wasted on its way from the farm to the fork and half of the population is pre-diabetic or diabetic.” One bag of Ambronite is designed to give a meal’s worth of nutrients, containing 500 calories and adequate amounts of vitamins, proteins and carbohydrates. Suoheimo says that reducing a meal to a portion of powder makes environmental sense because there’s minimal packaging and its long shelf life means food waste is reduced. Unlike with lab-grown meat, there are as yet no academic studies that have explored the sustainability credentials of powdered food. The ingredients in Ambronite are sourced from a number of countries: the Brazil nuts are imported from Bolivia, coconut flour from the Philippines and almonds from Spain. The berries are handpicked in Finland. Where possible, the company says it buys from organic farmers and producers.

Powdered food might seem like extreme lengths to go to for a more sustainable diet, so would money be better invested in getting consumers to understand food labelling and the value of cutting back on junk food? James Collier, co-founder of UK-based powdered-food company Huel, believes that it isn’t that straightforward.

“The current strategies designed to improve health are wrong. They focus on getting people to look at food labels and this can be misleading – it leads to [purchases] based on low fat content for example, rather than what will provide the best nutrition,” says Collier, who is an experienced nutrition consultant. “We should be encouraging people to improve their food choices, which is not just a case of reducing salt and sugar intake.”

Huel’s ingredients include brown rice and pea protein, flaxseed and MCT – a fatty acid typically used by endurance athletes. Similar to Ambronite, its products are vegan, avoiding the environmental impact of meat production.

The company can provide enough calories for under £6 a day. In comparison, Ambronite charges €75 (£50) for 10 of its supermeals, which works out at around €30 (£22) a day for a 2,000 calorie diet – a cost that could come down over time if production can be scaled up.

Huel ships to France, Germany and Sweden. Ambronite ships internationally, with the bulk of its customers in the US and Finland, where its two offices are based, and the UK and Canada.

Price considerations aside, how a food product fares is going to depend on how it tastes. Ambronite has a rich flavour somewhere between earthy and nutty, whereas Huel’s is more neutral and the company recommends that users add syrups or blended fruit to suit their own palates.

Drinkable meals have been touted as the end of normal eating, a claim that conjures up dystopian images of families in sterile kitchens queueing in uniform fashion for their servings.

“Food is a daily necessity, providing fuel, and for people on the go it’s perfectly possible that [powdered food will] prove useful, just as some people prepare [protein] shakes for a run,” says Tim Benton, a professor in population ecology at Leeds University. “But for most of us, most of the time, food provides a large variety of other functions, whether cooking for enjoyment, sharing with friends and family, cultural celebrations or even just to savour the flavours. These can’t easily be replaced by a quick fix. We need real food, and the social interactions around it, to remain human.”

Dr Joanna Kershaw, a senior lecturer in food science at Manchester Metropolitan University, agrees. “Food is much more than just nutrition,” she says. And though she can think of many applications for powdered foods, such as for those who have difficulty chewing or swallowing, for managing weight loss or gain, and for use on expeditions, “they can’t replicate the pleasure of eating”.

Despite scepticism, Huel and Ambronite maintain that there is a growing appetite for powdered meals, especially among those with busy lifestyles. Ambronite points to the success of its 2014 crowdfunding campaign, which hit its goal of $50,000 within a week.

“Home-cooked wholesome food is great for taste and texture, but some people don’t like the extra work of creating a meal plan, shopping, preparing, cooking and washing up,” says Collier.

“Normal food can, of course, be good, but creating a well-balanced meal that contains all the right elements in the right amounts isn’t easy. Huel can supply everything the body needs without the rubbish that’s in most diets.

As for fears that all our meals could become liquid-based, Huel expects people buying its product will use it to replace 50% to 80% of their food intake. As for Suoheimo, he loves to cook and has no intention of changing that.

“The goal isn’t to replace traditional food altogether,” he says. “It’s to create a real option of enjoying a full meal where people typically resort to poor fast food, snack bars, skipping meals and synthetic options, like sports supplements, that come nowhere near the nutritional completeness of real food.”