Solar Impulse 2's recent epic solar-powered flight across the Pacific made headlines as pilot Andre Borschberg broke a slew of records.

Lauded as a triumph of mental and physical endurance, Borschberg’s 118-hour journey also posed major challenges for Solar Impulse’s partner Nestle Research, which is devising the food for the historic round-the-world trip.

“It’s a cockpit that’s pretty limited in space – we have a limited allowance for weight,” Amira Kassis, nutritional scientist at the Nestle Research Center in Lausanne, Switzerland, told FoxNews.com. “Our job is to pack as much energy and nutrients in as little volume and weight as we can.”

Borschberg had 66 meals and snacks with him on the single-seater Solar Impulse 2, weighing 23.8 lbs (26.5 lbs including packaging). He also had 4 gallons of water and 1.6 gallons of sports drinks and nutritional supplements in the cockpit with him.

Related: Solar Impulse 2 reaches Hawaii, shatters records in historic Pacific flight

Kassis explained that three different types of warm meal were available to Borschberg – chicken with summer vegetables, potato gratin, and mushroom risotto. “We use a self-heating package,” she explained. “You have to add a little bit of water and there’s an exothermic reaction that heats the food – it’s a fabric bag that contains beads, with the contact of water there’s a chemical reaction that produces heat and warms the meal.”

The flight menu allowed for one warm meal a day, although this was supplemented with soups. Borschberg was also able to snack on Nestle Fitness cereal bars.

Kassis explained that the pilot’s food was carefully tailored to meet his needs at specific times of the flight. “The carbohydrates are given more at high altitude because they are an efficient and quick source of energy,” she said. “We use the lower altitude as a recovery phase – this is where we give protein to ensure that the muscles recover.”

Related: Solar Impulse 2’s epic journey in pictures

Solar Impulse 2 is the brainchild of explorer and Solar Impulse Chairman Bertrand Piccard, who is taking it in turns with his fellow Swiss pilot Borschberg to fly the solar-powered aircraft on its journey across the globe.

Both pilots have been carefully assessed at the Nestle Research Center, according to Kassis. “There’s energy needs, depending on the age, height and weight of each pilot – we measured their energy expenditure in the lab here,” she said. “There’s also protein requirements based on the physiology of each pilot.”

The menus developed by Nestle Research were then tested during the pilots’ 72-hour stints in a flight simulator and also during Solar Impulse 2 test flights.

Last week the Solar Impulse team announced that the second leg of the plane’s flight across the Pacific has been postponed until 2016 while it undergoes repairs to its damaged batteries.

Related: Battery damage grounds Solar Impulse 2 until 2016

Piccard’s diet when he flies the next leg will be similar to Borschberg’s on his trip from Japan to Hawaii, according to Kassis. “The structure of the diet is almost the same – we’re still in the small, frequent meals,” she said.

Solar Impulse 2 set off from Abu Dhabi in March, and has stopped in Oman, India, Myanmar and Nanjing, China, en route to an unscheduled stop in Nagoya, Japan.

The plane originally left Nanjing, China, for Hawaii, but diverted to Japan on June 1 because of unfavorable weather ahead. It had been waiting for the right conditions to depart before Sunday’s takeoff for Hawaii.

After Hawaii, the second Pacific leg of the journey will take the plane to Phoenix. Solar Impulse 2 is slated to stop in New York before flying over the Atlantic Ocean. It will then stop in southern Europe or North Africa, depending on weather conditions.

Follow James Rogers on Twitter @jamesjrogers