High frying a scientific quandary

LOSING WEIGHT: Bryan Caldwell in the weightless environment of zero gravity.
LOSING WEIGHT: Bryan Caldwell in the weightless environment of zero gravity.

It took Kiwi space researcher Bryan Caldwell four flights over two days in Nasa's multimillion-dollar space research aircraft to conclude that cooking on Mars would be messy.

Caldwell, a researcher at New York's Cornell University, is currently stationed in Galveston, Texas, where he is researching why astronauts lose their sense of taste in space.

And when a colleague wanted to test out what cooking in space would look like, Caldwell leapt at the chance to join her.

Eventually, when bases are established on the Moon and on Mars, astronauts will possibly be able to do regular cooking - not just the rehydrate-and-microwave approach taken on spacecraft these days.

The researchers wanted to know how hot oil would behave when frying in Mars' gravity, which is one-third as strong as Earth's, or on the moon, where gravity is one-sixth of Earth's.

Caldwell and researcher Susana Carranza took a specially constructed space galley onto Nasa's "vomit comet" - officially a "reduced gravity aircraft" - a plane that flies parabolic paths periods of weightlessness lasting 30 to 40 seconds. By altering the parabolas Nasa can simulate lower-gravity conditions and it was in these conditions that Caldwell and Carranza tested-fried tofu and hash browns.

Using canola oil that had been dyed red, they put photographic paper around the cooker to measure the splatter of low-gravity frying.

The results are still being analysed but Caldwell said the droplets of oil seemed to splash further out of the pan than on Earth and settled in "slow-motion".

"It's going to be a messy business," Caldwell said of cooking on Mars.

The experiment was also designed to test flash points of the oil and how far the fumes would travel - important aspects on a potential Moon base where you couldn't just open a window if you burned the cabbage.

It was a long way from Auckland, where Caldwell worked as a theatre lighting designer for "20-odd years" before he decided he wanted to be an astronaut.

He got a PhD in Auckland and then got a post-doctoral research position in America where he pestered Nasa with calls every few months.

His current work looks at why after a few days in space, food starts tasting terrible.

Even foods as strong-tasting as coffee start tasting bland and lose their "complexity", he said.

The current hypothesis was that because gravity is not dragging the blood from astronauts' heads, their heads get puffy and their nasal tissues get stuffy, blocking their tastebuds.

To test this, Caldwell has a team of paid test subjects who spend 70 days in bed, tilted with their heads below their feet.

It's a tough test but everybody is psychologically screened as they are never allowed to get up - not for eating, toileting or showering.

Initial results suggest subjects start disliking foods about halfway through the test period.

"Some definitely have a change in their smell ability. Some menu items, like egg salad, they like at the start but stop liking later on."

Caldwell said his experience in the zero-gravity simulator was "more than he could hope for".

And for the record, despite the plane's nickname, he managed to keep his low-gravity tofu in his stomach, not on the walls of the "comet".

Sunday Star Times