Space travel can be boring. Voyages to Mars or the Asteroid Belt may
sound exotic and exciting, but the fact is that most of the time there’s
not much to see and not much to do. Wouldn’t it be great if morale on
these long missions could get a boost by a reminder of home like fresh
baked bread? Thanks to NASA’s “Space Apps” program, that might one day
be a reality. Sixteen-year old “citizen scientist” Sam Wilkinson has
come up with a way to make bread simply and efficiently using carbon
dioxide and a slow cooker that is designed to work within the
limitations of a spaceship’s galley.
Sam Wilkinson has come up with a way to make bread within the limitations of a spaceship’s galley (Photo:Shutterstock)
But this isn’t just a matter of astronauts sitting down to a breakfast
of fresh, hot bread groaning with butter and jam (nice though that may
be). The process also addresses a very serious problem as man ventures
into deep space: how do you carry enough food to feed a crew on long
voyages? Up until now, the cuisine on manned missions has consisted of
pre-prepared, pre-packaged meals. They may have seemed like something
off the menu of the future during the Gemini and Apollo missions, but
from then right up through the missions aboard the International Space
Station, it’s all just box lunches.
And that’s the problem. Pre-packaged meals take up a lot of space and
the packaging adds a lot of weight. That’s fine for short missions in
low-Earth orbit, but on a mission to Mars that may last two or three
years, that’s a lot of plastic trays and squeezy bags to cart along. One
answer to this is to carry food as raw, bulk material like on maritime
ships. In other words, a Mars mission would ship frozen sides of meat,
containers of dried peas, No. 10 cans of powdered eggs and sacks of
flour - or better yet, unground grains. But in order to do that, future
spaceships will need proper galleys and astro-cooks will need to know
how to prepare food in zero gravity with the limited resources available
on a spacecraft.
The science of bread
Bread is pretty simple. It’s basically just flour mixed with water. If
you take this, flatten it out and bake it, you get an unleavened bread
like a matzo or a tortilla. But if you want something more like a loaf
of bread, you have to make what’s called a leavened bread. The key part
of baking leavened bread is getting it to rise. If you don’t manage
this, you end up with a freshly baked brick. This is usually
accomplished by adding yeast. If the temperature is right and the proper
amount of salt is added to control the process, the yeast cells will
feed on the sugars, start to reproduce and as they do so, they give off
carbon dioxide gas. This gas is trapped by the gluten in the dough,
which forms bubbles and the dough starts to rise.
The alternative to this is using a chemical, such as baking soda or
baking powder, both of which use sodium bicarbonate to produce carbon
dioxide and are generally used in quick-rising breads, such as cakes or
biscuits.
This has served bakers and householders very nicely for some six
thousand years, but baking bread in space has its own problems. Any
spaceship designed in the near future is going to be small, cramped,
provide very small amounts of electrical power, ration cargo space like
it was gold wrapped in gold and won’t have a galley anything like the
one on the Starship Enterprise. It will very likely be some tiny,
underpowered alcove intended to do too much with too little. Therefore,
baking bread in such an environment has got to be as efficient as
possible - more bread machine than artisan bakery. More important, it
has to be able to work in zero gravity. All of this puts both yeast and
any chemical leavening agent at a disadvantage. For one thing, the
chemical version needs to be carted along, which adds weight. Yeast
doesn’t necessarily have this problem, but the alternative is
cultivating it during the mission, which may not be possible in zero
gravity or be logistically feasible.
Space bread
This is where Sam Wilkinson’s process comes in. The magic of making
bread rise isn’t in the yeast, it’s in the carbon dioxide and you don’t
need to ship CO2 on a manned spacecraft - you’ve got more
than enough thanks to all those astronauts breathing. Wilkinson’s idea
is to use this “found” carbon dioxide to make the dough rise.
Sam Wilkinson's approach uses “found” carbon dioxide to make the dough rise
The next step is to take the dough and bake it in a sealed, very low
temperature oven at about 120 C (250 F) for one hour and ten minutes.
This is a method that is commonly known as “crock-pot bread”. It takes
longer than oven baking, but is much more efficient in terms of power.
Only between 120 and 280 watts of power are needed to bake a loaf, which
is a considerable improvement on the 1500 watts needed in an oven. On a
power-strapped Mars ship, this is a significant savings.
Part of the reason for the sealing is to retain moisture and, according
to Wilkinson, improve the Maillard effect, which is what forms a proper
crust on the bread by the reaction of amino acids and sugars (this can
also be done by a quick blast of heat after baking) as well as reducing
crumb formation. This is of particular importance aboard a spacecraft
because crumbs have given engineers the heebie jeebies ever since the
first Mercury flights when they feared the aftereffects of John Glenn’s
lunch would end up in the capsule’s machinery. That’s the reason why
early astronauts’ sandwich cubes were coated with gelatin and why the
ISS only serves tortillas.
At the moment, space bread is still in the proof of concept stage, but
it may be that when the first astronauts land on Mars, they’ll have
fresh pumpernickel for their sandwiches.
Sam Wilkinson runs us through his space bread baking process in the video below.
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