the history of food is to history of
humanity a lot of our social life is
organized around food
it's a story that is continued his man
has ventured into space the iron content
of the astronauts diet should be lower
than the diet on earth in space
I just hated sweet my mother gave me a
coffee with sugar
I couldn't actually don't think one of
the Apollo astronauts very proud that he
was the only human who has ever the
spaghetti on the moon surface as we've
got longer missions and future voyages
of exploration research into food and
nutrition is at the forefront of the
effort to travel to build bases on other
planets in our solar system the target
foremast mission is to be able to
recycle of the forty percent of the food
most of us in Europe are lucky enough to
take food for granted
yet if you really think about it we
still spend a great deal of our lives
getting preparing and of course eating
stuff
in fact for most of human history the
majority of people spent all their lives
just producing the food they needed to
survive and in many parts of the world
this is still the way
millions of people live it was only in
the nineteenth and twentieth centuries
that many of us left fields and migrated
to towns and cities to work in the
factories and offices of the modern
world's
the reason that food is such an integral
part of our lives is because it provides
the fuel that we convert into energy
this tractor needs fuel to work but
instead of running on diesel our bodies
unlock the energy we need from the food
that we eat this makes food and eating a
huge part of our lives
but food is much more than just fuel
from the moment you were conceived and
begin to develop your mother's womb your
body has been getting most of the raw
material needs to build and repair
itself from nutrients in food and it's
exactly the same space to spend more
than a few hours in space we have to
take supplies of food and water with us
I'm alive scientists working for the
european space agency easa it's either
there are thousands of scientists and
engineers involved in research into how
we can live in space we have a big
challenge ahead of us as we permissions
to other planets we have to find ways of
building space forms and actually
producing food and water in space
many of these projects are being tested
on International Space Station the ISS
the ISS has been built form of
kilometers above our heads in
international effort of research and
space exploration traveling at 28,000
kilometers per hour
it always the earth 16 times every day
but to really understand food and
nutrition in space
let's find out exactly why we need food
and how we converted into the fuel and
other essentials for life
for any physical or mental activity
that's a little competing on this course
our bodies need energy every time we
speak link and even dream we use energy
the cells in our bodies use the energy
stored in food for everything from
building proteins copying genetic
information and of course moving or
muscles believe you're not our brains
use more energy than any other single
organ in your body just thinking uses
twenty percent of the energy we need
house energy stored improved in the
first place
food is mostly made up from three groups
of chemical compounds carbohydrates fats
and proteins carbohydrates and fats are
mostly used for energy most protease are
the building blocks for every cell in
our bodies
but what foods do we need to eat to get
these essential ingredients foods like
bread and pasta are full of
carbohydrates we get fats for milk
cheese and vegetable products such as
oil and we get proteins again from
animal products for some vegetables such
as soy food also gives us the important
minerals and vitamins that our body's
needs to rebuild themselves and control
vital chemical reactions like the crude
oil that is popped out of the ground
then converted into the petrol and
diesel for our cars our bodies have to
process foods to get to the stored
energy that is chemically locked up in
food the first part of this process is
digestion as soon as food has entered
the math and effects
proteins and carbohydrates have begun
the journey through the body the process
of digestion begins
suggestions a process that requires food
and gifts of heat and energy
it does this by breaking down the
complex molecules of food into simply
more readily absorbed molecules
digestion happens as the food travels
along the elementary canal or are got
the gut is a muscular tube that uses
peristaltic action to squeeze the food
from my mouth to our anus fire stomach
and intestines during its passage
nutrients are extracted from food in
several processes this starts in the
mouth where food is broken into small
pieces biomechanical acts of chewing our
library plans also get to work and for
use an enzyme called amylase which
breaks a chemical bonds and
carbohydrates releasing shooters the
partially digested food isn't
transported to the surface into the
stomach the journey action of the
stomach further breaks and food and
mixes it with gastric juice the stomach
is a muscular sack when empty it's the
size of a sausage but it stretches to
the size of a large melon when full food
remains in stomach for between 30
minutes and four hours in stomach
Simon cells secrete pepsi no gene which
is converted in the protein speeding
enzyme pepsin the gastric juice and a
stomach is mostly hydrochloric acid is
about 1 million times more acidic than
tap water
it provides the optimum ph for pepsin
and also Dean ages proteins into
polypeptides and softens connective
tissue in meet the next stage of
digestion happens in the small intestine
but further enzymes break down the
polypeptide chains into amino acids
carbohydrates into glucose and fats into
fatty acids and glycerol these are end
products of digestion
these simple molecules together with
vitamins minerals and water are then
absorbed into the bloodstream in the
small intestine and transported to where
they are needed in the body the most
important Angie molecule that the
digestive system extracts from food and
transfers through the bloodstream is
closed commonly known as blood sugar if
you have low blood sugar levels you will
have a lack of energy excess glucose
distorted flies gin in the muscles and
the liver and converted back into
clothes when required
glucose is supplied her body cells by
the bloodstream but ourselves cannot get
the energy directly from cucos the
converted into a form that they can use
the molecule ATP glucose molecules are
broken down by a process known as
cellular respiration this process
consists of three of lives most
important biochemical reactions
psychosis the kreb cycle and the
electron transport chain collectively
the system converts each glucose
molecule into approximately thirteen
molecules of ATP it's an extraordinary
fact that the billions of cells in our
bodies produce half of our own body
weight of ATP every day and then burn it
for energy after the digestive system
has extracted all these vital
ingredients from the food we eat what's
left passes to the large intestine where
water is extracted and waste materials
produced which eventually passes out of
our bodies so that's how our bodies
digest food but exactly how much and
what kind of food should be eating to
stay healthy
we've seen how our body get the energy
and the building materials at our bodies
need from the food that we eat but
exactly how much food do we need to
understand this we have to carefully
calculate how much energy is contained
in food one way of measuring this is
with a bomb calorimeter the energy food
is counted in kilocalories common usage
has shortened kilocalories to calorie
one calorie response to the amount of
food that when burned erase a
temperature of 1 prime of water by one
degree Celsius the average grown man its
approximately 2,500 people calories a
day and women about 2,000 a lot of the
calories we consume are needed just to
keep us alive before we do any work
this is called the basal metabolic rate
and we use between a tonic and 1,400
calories to keep her brain heart and
other organs taking over a balanced diet
that supplies the correct amount of
calories and nutrients is fundamental
for a healthy body and a healthy life
our nutritional needs depend directly on
the amount of work our bodies do the
sports person its many more calories
than someone who spends all day in an
office or classroom getting very little
exercise if you consume more food than
your body actually uses for energy it is
stored as fat our bodies have evolved to
store excess energy supplies in facts in
case we needed for the future when there
is a food shortage
the trouble is that for most of us in
the developed world we usually have
plenty of food and don't need to rely on
stored fats
in the last two decades sedentary
lifestyles and unhealthy diets has led
to the problem of many overweight adults
and children worldwide being overweight
is a major contributor to serious
diseases such as high blood pressure
cardiovascular disease and type 2
diabetes if we eat more than our body's
needs our diet is set to be unbalanced
in space and asteroids food intake has
to be the ultimate balanced diet they
have to give top performances every day
in the most hostile environment in which
human beings can survive so their food
has to be both nutritionally balanced
and tasty but weigh as little as
possible wrong estimate of the
nutritional needs may be harmful to your
health it can lead to tiredness muscular
atrophy and cardiovascular problems so
the essence diet is carefully monitored
whilst in space by flight surgeons like
dr. philippe longer all the nutritional
intake is monitored in the sense that we
know what has been both on board for
that astronaut so we're able to know in
terms of nutrients and in terms of
calories what the astronaut is going to
eat and that choice has been made on the
basis of the needs of the asteroid has
that has been calculated on earth
including of course the physical
exercise on the space station the asset
is exercised in a couple of hours per
day so there's a lot of calories that
are burned just by physical exercise
extensive research has shown that
estimates actually use slightly fewer
calories when in space
it's not just calorie intake that needs
to be monitored in space is a
nutritionist have discovered some
important differences between a balanced
diet on earth and a balanced diet for an
astronaut in space the iron intake in
its face should be lower than on earth
because in space the astronaut has a
lower classmen volume and the lower
Earth aside William so at the beginning
of space rock there's a breakdown of the
democracy in which contains the island
so more iron is available so that's one
of the exceptions the iron content of
the astronauts diet should be lower than
the diet on earth
vitamin D is also very important for
healthy bones our bodies usually make
vitamin D when our skin is exposed to
sunlight spacecraft are shielded to
protect the astronauts from harmful
radiation and access sunlight astronauts
in space on the in the ISS don't have
that much sunlight so they don't have
that constant the size ytmnd so what we
right now add is about 800 international
units of vitamin D with the space hood
but it's not just about what we eat when
we eat can also dress it improve
performance
this is where astronauts can learn from
the field of sports science
well there are many powers and what the
physician is doing together with the
astronaut is very similar to what the
culture or a medical doctor does
together with the athlete the so is
really improving optimizing his level of
health from a mental and physical
perspective here telling Thames some of
the world's top rowers train to achieve
the optimum physical and mental
performance Olympic rower Tony carpet
knows all about getting the optimum
performance out of his body
how important is a balanced diet for
anything like you to keep fit through
training what i find it really important
to make sure you eat correctly the big
thing over door where I guess
carbohydrates because without the
glycogen stores which are which is what
stored in the muscle that is absolutely
key if you get that wrong you're gonna
be in trouble why advise people really
is to try and look at what they call
complex carbohydrates which is brand
porridge oats homebred gives you the
energy for a little bit longer so you
don't have the dips in energy that's the
dips in performance when we go into more
side weight based training i always try
and think about having more protein as
well I'm so combine the two together and
they've done some recent study too so
that actually taking on protein and
carbohydrate after hard strenuous
exercise within the 20-minute window
health recuperate the body but it's
actually quite a natural balance diet
really is quite simple stuff we're just
making sure that you're having it evenly
spaced out throughout the day were in
regular intervals so we've heard of food
can be used to optimize an individual's
physical performance but there's a lot
more to food and simply its effect on
the body
as important as food days is the fuel
and the raw material bodies needs it's
not the only reason we eat another very
important role who plays in our lives is
a psychological one eating and sharing
food with other people is probably
always communal act that we know it's no
exaggeration to say that the society we
live in today at the beginnings in the
act of obtaining and sharing food in
groups you can see this in all social
animals long before we start farming we
work together hunting and gathering food
the eating and sharing food from the
basis of societies throughout the animal
kingdom
nowadays this is of course changed and
we get most of our food from the
supermarket and we eat alone a lot more
than our ancestors but eating together
is still a fundamental part of our daily
lives and the importance of it is
recognized by asteroids psychologies
professor determines I if you want to
socialize his friends with other family
members even with its people we do not
know where we well we make appointments
for a common dinner or a common lunch we
have work lunches so that a lot of our
social life is organized around
the ISS is thick enough that may be
astronauts do not need too much during
the day so what we have decided for the
ISS program is that we want the crew at
least once a day to have a common meal
we make sure that the dinner at night is
made or together so we have the time of
the dinner at the time after you can
talk together at the social event
discuss have drugged and this is
important for the cohesion of the crew
we want at least to give them
possibilities to communicate and
formally together and this is highly
valued I think for my point is it's
psychologist whatever is very small 4-6
mature to to find a way to be or
together and to prepare your food then
you the special food for Christmas or
birthday we bring some food for a nice
chef in Europe and this is really
appreciated by our own astronaut but
also by the old community of estimates
food is also a kind of national thing so
to get food from your home country which
probably most fit to your personal
preferences i think is very important
from time to time
we've seen how cruise on the ISS to
change from a range of foods particular
to their own personal taste and culture
this demonstrates a huge diversity of
foods the different cultures have as
part of their staple diet however is
that versus the food we've grown up with
is and is now available for cruising
space it wasn't always so
the food that the first estimates
experience is a testament to the
pioneering spirit they had to end your
cubes of called the hydrated food that
relies on her own saliva to rehydrate
and taste the space squeezed out of
toothpaste like tubes
the food was on advertising and not
surprisingly they're really this like
squeezing it out of troops directly into
the mouth by the time of the Apollo moon
missions in the late 1960s the quality
and variety of food and improved
enormously the Apollo spacecraft had hot
water which made rehydrating foods
easier and improve the taste and for the
first time estimates were able to enjoy
the food in space one of the Apollo
astronauts very proud that he would be
on human has ever the eating spaghetti
on the moon surface in the 50 years
since we first put humans in space space
food went from unappetizing concoctions
23 * dishes papers of the world's most
renowned chefs either has cooperated
with European ships to provide
high-quality space food
they also created special meals for
estimates to celebrate New Year
birthdays in the arrival of a new crew
over 200 recipes are now available
during training astronauts are invited
to choose which means they would like to
eat on their next mission dishes range
from chicken teriyaki to fruit salads
beef stroganoff and butterscotch pudding
a few months before the mission they
make you choose between the something
like 500 different males and you test
food not in one day because you have so
you do that in a different days and you
you can say i prefer this food and you
can say I don't like this food but the
nutrition are looking at your foot in
terms of a balance of vitamins and and
the quality for your body so even if you
don't like the type of food you might
have it in your package remember for my
flight for instance i was surprised
because for for breakfast I had fish we
have costs on cafe but do not have fish
so you have to get used to it it's not
just the ordinary surprise in the food
package that estimates have to look out
for it seems to spending time and space
affects the astronauts sense of taste
what astronaut anecdotally tell us is
that they use taste and smell sensations
in space and that's probably one of the
reasons why the space was so high in
sodium content because more sort of food
tastes better than other food from me i
really like sorted food but in space i
wanted even more fully functional and
on-the-ground I don't like too much
sweet but in space I just hated sweet my
mother gave me a coffee with sugar
I couldn't I couldn't drink coffee we
should have because it was too much
sugar so you your test as a complete to
change a little bit in space compared to
the ground
having created this fantastic range of
foods for astronauts the next
consideration is how to get into space
even gracious food has to be preserved
before it's taken into space food
scientist Mike Lewis is responsible for
developing techniques that will preserve
astronauts food but he is just the
latest practitioner of techniques that
were used for millennia mankind is being
preserving food in lots of ways going
back 4,000 years salting sugar
preserving food preservation is very
very old and very traditional the main
purpose of preserving foods is to
inactivate the microorganisms or
microbes are naturally present or
preservation methods involve preventing
the growth of bacteria foggy and other
microorganisms as well as regarding the
oxidization of fats which caused from
city in today's high-tech food industry
a variety of techniques are used to
preserve food many of which we may not
even be aware of foods that we buy may
have been killed disaffected or
irradiated in order to slow down
microbial action most of the food
consumed by astronauts in space has been
preserved in some way the two most
common methods of preserving space food
for sterilization where food is heated
to 121 degrees centigrade in a sealed
can and dehydration where water is
removed during the development of
microbes and reducing the volume of the
food
but whatever technique is used to
preserve food for use in space the
original properties of the food are
inevitably altered and George Grimble is
researching the consequences of this
does food preservation degrade the
quality of food and degrade its
nutritional value and the answer has to
be that it depends on the process that's
being used to preserve the food a lot of
researchers gone on to try and minimize
nutritional changes during food
processing for example peas
um if you buy them they've been on the
market stall for two days would have
lost a considerable amount of their
vitamin C and one of the advantages for
example of quick freezing is to minimize
those sorts of changes what you'll often
find is that particularly sensitive
components in food for example vitamin A
or this mini can be degraded by
atmospheric oxygen and what this means
is that you have to take into account
during the processing the amount of
vitamin was degraded and then add an
amount back into the food to make sure
it reaches the right level
astronauts don't have to rely only on
preserved food the ISS has resupplied
every few months so estimates are
patiently enjoy fresh food when a
resupply craft has just arrived the
biggest differences between space food
and food on earth our packaging methods
space food must be carefully contained
so it doesn't float around in the free
for environment the fullest to be kept
in kind of source if it is too dry
likely to rise to divide the rise with
file use food particles on board the ISS
could cause serious problems not only
for the machinery of the spaceship
itself but for the astronauts health
this is dr. because you can't keep your
highs with morrigan you can bring it and
you can put in your life and it is very
bad for this reason things as common as
salt and pepper have to be provided in a
liquid form but liquids can float away
as well so drinks like coffee fruit
juice and tea packages powders and
sealed in squeezable containers as much
just add water to drink to rehydrate
them and bring them with straws the isis
has a kitchen that is equipped with food
storage compartments food warmers the
food preparation area a table with
restraints
so the estimates don't float away was
eating and metal trays that stopped the
food packages from floating away but
this all depends on food that is
regularly resupplied from Earth in the
next section I'm going to find out how
either plans to feed astronauts on
missions lasting as long as three years
here on international space station the
next meal is only supply ship away but
how do we feed the crew of six
astronauts on a three-year mission to
Mars iza and the other international
space agencies are planning manned
missions to the Moon and Mars in the
future for that length of time the crew
of six will need many tons of food and
drinking water let alone all the other
vital supplies that they would require
scientists are researching how to extend
the shelf life of food for up to five
years while maintaining a variety of
great tasting foods
however the most powerful rocket in the
world today can only carry a payload of
a few times into space and a trip to
Mars we need many tons of food and
supplies the only practical way to
supply long term missions is to Lord the
equivalent of a farm into space and grow
at least some food while recycling water
and waste to supply the crew for long
periods of time when we started with
bases on the moon and mars we also have
to grow food and recycle waste to an
able to stay on these distant planets
for years at a time
Issa has a number of research project
for growing and recycle food into space
easy societies is a piña works on one
of these the melissa project the
minister project addresses actually the
supply of air water and food for the for
the crew in a close to ready originality
of system in the sense that we take
actually the waist which are produced by
air by the crew being about physical
material urine that we degrade and from
that young regenerate and the water the
air and we produce as well
food today the target for mass missions
is to be able to recycle every forty
percent of the food why 40-percent of
the food because if you recycle produce
forty percent of the food of the cool
directly you produce and what percent of
oxygen and on what portion of the water
cool we'll need the question of which
foodstuffs to actually grow in the
precious reclaim resources is not simply
a scientific one there is another
criteria which is very important is the
quality of the food you will need to
produce you can feel the requirement
devil nutritions with with only but you
have to consider the acceptance and if
we feed the cool with only with of
course we will have had some
difficulties you just want to get a
fresh tomato or fresh cucumber or fresh
fruit
melissa is already successfully trialed
a close water recycling system but this
technology is not just applicable in
space you know that today everybody is
challenged by the environmental issue
and global warming issues specifically
the water quality is your quality
contaminants and everything and we know
already because we have some success at
the minister technology is applicable to
us which are already used in the test
your application and I think it's
important that people realize this is
the beginnings of the exploration of
space there have been many technological
spin-offs from advanced composite
materials to gps that we all use in our
phones and set
lives every day and in a world of
increasing population and decreasing
resources systems such as Melissa
developed for space travel could be the
most invaluable spin-off yet we've seen
in this program that food is literally
the fuel of life on earth and in space
ensuring adequate supplies of food
always has and always will be the most
important activity that all living
things from plankton to planetary
explorers do as we've seen the logistics
of long-term spaceflight require huge
technological innovations to supply
cruise with the food they need both for
the physiological and psychological
well-being SE travel to distant planets
the earth is a self-sustaining ecosystem
a man spacecraft that will be away from
its homecoming for years will also have
to be a self-sustaining ecosystem or to
put it another way a miniature planet
Earth in many ways the technological
challenges for ensuring future crude
supplies on earth are the same as in
space
ok
ok
ok
ok
person around it doesn't have TV
coverage of the things that man got the
black up now you're gonna feel started
getting a TV picture never fail us we
are getting a
your picture
one bad way
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