Breathing on a smartphone could help to determine what is healthy, and a takeaway might be tasted virtually before it is ordered, it is being suggested.

Something dubbed BreathTech could be developed, allowing "a deep level of insight" into the foods you should be eating, a report commissioned by Deliveroo said.

Diets that fit with someone's personal physiology would be powered by artificial intelligence (AI), while a life-long AI "buddy" would help to automate and tailor what you are eating.

Another suggestion is that virtual and augmented reality could be used to trick people who steer clear of vegetables into thinking they are eating chocolate or sweets instead.

If someone wanted to cut down on alcohol, then "wine" cordials, which mimic the taste and flavour profile of real wine, might be introduced.

Alternatives to staples such as corn and maize, such as amaranth, fonio, sorghum, teff, khorasan, einkorn and emmer, are all predicted to be mainstream in 2040.

Another predicted trend is "edible beauty" products, which could include anti-ageing ice cream and the chance to dine from hormone-balancing and dopamine-driving menus.

The report, called Snack to the Future, also envisages virtual reality dinner parties, allowing consumers to create dream scenarios, perhaps involving celebrities.