At a time when airlines are battling it out over passenger seat width and excess baggage fees, British Airways (BA) has turned its attention to another key challenge of the airline industry – bland airline food, a result of dry cabin conditions and high-altitude pressure that appear to suck the flavours out of food.

The British carrier has found the answer in a not-so-secret Japanese ingredient called umami, known as the "fifth basic sense" alongside sweet, sour, salty and bitter, the Wall Street Journal reports. First discovered in Japan by the scientist Kikunae Ikeda in 1908, the distinct taste was found to be the key savoury factor in various foods including tomatoes, meat, Parmesan cheese and other foods.

Over the past year, BA has reworked its airline menu to incorporate more umami-rich dishes to help counter the bitterness found in food served at high altitudes, according to new studies carried out by British Airways and the Leatherhead Food Research. Cold temperatures, grey cabin lighting and high stress levels were also found to dull passengers' tastes of food, according to the study.

BA's new tasting menu, devised by the five-star Langham hotel in London, for first-class cabins in the Airbus A380 super jumbo jets features new recipes targeting high-altitude dining, including pork belly and pork cheek with lime and lemon grass sauce as well as heritage carrot, pak choi and peach.

The 'umami factor' was introduced to BA by Heston Blumenthal, the chef known for his experimental and scientific approach to food, following an episode on his Channel 4 series Heston's Mission Impossible where he attempted to serve food made from scratch to passengers at 35,000 ft.

"You can't load more salt but you can definitely up the umami," he said on his show.

The airline has also been upping the fruit content in their white wines and minimising the bitterness in their red wines (said to be magnified at high altitudes). It has also installed steam ovens in its first-class cabins which help to heat bread without hardening it.

BA has also worked with the English tea brand Twinings to create the blend of its Kenya, Assam and High Ceylon teas that would taste best at high altitudes.

Airline meals are an important element of the on-board experience for long-haul flights as well as business and first class cabins where passengers' expectations are higher than other classes given the prices they pay.

As well as the food quality, passengers are also concerned about price. New research this summer revealed that airlines charge up to 2,600 per cent more than supermarkets for in-flight food and drink. Budget carriers such as easyJet and Ryanair were singled out for applying the biggest mark-ups.

Last year, a study suggested Ryanair passengers could find themselves paying more for snacks on board the plane than for the flight itself.

The Telegraph, London