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#201 2015-12-17 20:17:13

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Crops

SpaceNut wrote:

Nice information but if we are in need of such indoors plants then why are we not doing so on the ISS were we would learn lots more about the long term effects of such chemical hazards. One that the astronauts have been around is ammonia which is used in the cooling loops. Are there any of the others onboard?
Of course Mars would be different but we could be still using many of these still unless we plan them out of possibility.....

One that isn't mentioned much is free floating faeces - a problem on early ISS missions I believe! But I think hygiene control has improved over the decades...


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#202 2015-12-17 20:41:56

RobertDyck
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Re: Crops

I have a cat. Ammonia is off-gassed from cat pee. Human urine is flushed down the toilet, but the litter box...um. That's why I looked for a house plant that would remove ammonia, yet is safe for cats. The ACSPCA list includes every ammonia removing plant on NASA's list. Expletive!

If you recall, Terry Kok was founder of the Green CELSS TaskForce. He advocated a composting toilet, and actually built one attached to his home. He has detailed microbiology to go along with his composting process. I was thinking that's a fancy outhouse, so an ammonia removing plant may be a good thing.

The Green Hab team based their work on a grey water sewage processing system. Perhaps better; requires more water, but that water is recycled. Still, if the treatment tanks at all open to the habitat, ammonia removal would be good.

ISS relies upon activated charcoal to remove organics such as these. The organics removed have to be baked out periodically. What happens to them? I assume they're just vented to space. Houseplants would reduce the need for this, so reduce the need for energy to bake-out the charcoal, and yet another loss to the system that can be recycled.

Last edited by RobertDyck (2015-12-28 23:04:29)

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#203 2015-12-28 19:24:44

SpaceNut
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Re: Crops

How to grow Space Age veg

nasa-plants-rex-xlarge_trans++eo_i_u9APj8RuoebjoAHt0k9u7HhRJvuo-ZLenGRumA.jpg

Now thats a garden....

“To grow plants in space, you need to recreate a complete environment – the root zone, the atmosphere, temperature control and humidity. They are not exposed to direct sunlight: the lighting is powered by the space station’s electrical source,” says Christophe Lasseur, project manager at the European Space Agency (ESA) initiative MELiSSA, the experimental Micro-Ecological Life Support System Alternative that could revolutionise space travel.

Essentially, the MELiSSA partners aim to create a closed loop life support system with close to 100 per cent efficiency – a self-sustainable ecosystem that ideally does not require resupply. “Plants are part of the mix; they become a technology to transform carbon dioxide to oxygen, waste water to drinking water and to create edible biomass,” says Lasseur. Selected plants must provide a balanced nutritional profile; they must also be highly efficient and grow well in the very specific conditions of a spacecraft.

“We aim to grow plants with minimum root-level water, to reduce mass and the opportunities for microbial contamination. All plants have advantages and weaknesses: tomatoes can be eaten fresh, but they have a lot of non-edible biomass. Wheat grows fast and at high density, it has very good gas recycling, but it requires processing before eating. Lettuce is almost all edible, but it is nutrient-poor.”

The MELiSSA ecosystem has a compartment for the crew, one for plants and three fermentation chambers – essentially a process of high-speed composting – recycling waste materials from the crew and mission, before feeding them back to the plants. It takes to a nuts-and-bolts level the much larger, more complicated environment of Earth. While conventional terrestrial life allows for a blissful detachment from the realities of recycling human waste, astronauts require a robust attitude to close-quarters living. And, anyway, the alternative is failure to survive.

So the ISS has been useful for research after all...

The top 10 plants to grow in space

1. Soybean
Soybeans are amazingly rich in protein and oil, and can be made into products such as soy sauce, while the immature pods are eaten as edamame. Dried soya can be found in many other foods and drinks, as well as essential products from paper to adhesives. After processing, the oil from the seeds can also be used as a diesel fuel – a useful plant.

2. Potato
Humble they may be, but few crops produce as much food per square metre. Although mostly carbohydrate, they contain high-quality protein and useful amounts of vitamin C. Older varieties are often robust, water-efficient and high yielding, if not so easy on the eye.

3. Rice
Rice feeds nearly half of humanity, and it would be unthinkable to leave this behind. Paddy rice (grown in water-filled paddy fields) might be tricky in space, so perhaps the less important dry land rice (grown in dry soils) would be the interplanetary choice.

4. Soft white wheat
Used to make many of the staples of our diet, from bread and pasta to couscous. Modern British wheats are bred by specialist companies for use in mechanised farming and as such carry royalties. Rather than returning astronauts facing a hefty bill, we suggest working with the International Maize & Wheat Improvement Centre, who can advise on royalty-free wheats that can withstand arduous conditions and have little straw content.

5. Tomato
Tomatoes are a must. Imagine life without this tasty, vitamin rich succulent fruit. It can be eaten fresh or used in cooking. Good cultivars include the bushy 'Red Alert’ that is extremely fast growing, producing abundant small sweet fruits.

6. Spinach
Spinach is quick-growing, can be eaten raw or rapidly cooked, and its sharp flavour would be especially welcome on long voyages. Astronauts would be wise not to gorge, however, as the oxalic acid it contains can limit dietary uptake of calcium.

7. Lettuce
Quick and easy to grow, produces limited waste, and fresh tasting, important for travellers confined to their craft for long periods. Lettuce was originally grown for its oil rich seeds and these too might be valuable in space. Cos, also known as red romaine, was recently grown and eaten on board the ISS, marking the start of the 'veggie project’ that will see more food grown in space.

8. Beetroot
Beetroot is a sweet, tasty and nutritious root crop, and its leaves make a filling, robust spinach-like vegetable. In theory, sugar beet would be heavier yielding, but of little use in space where processing factories are few.

9. Onion
Lengthy missions would be dull indeed without these nutritious, flavour enhancing vegetables. They also have an analeptic (stimulating) effect on the central nervous system helping to keep astronauts alert. Onions like a hotter, sunnier climate, so varieties that perform well in Britain should grow anywhere.

10. Spirulina
Not very appetising but in the worst case scenario space explorers would be able to survive on this green micro-alga. Harvested form the ocean, it is protein rich and efficient at producing oxygen from waste carbon dioxide breathed out by the crew

For further information on Rocket Science visit rhs.org.uk/schoolgardening. See also melissafoundation.org and esa.int

So we have part of a menu of items and why we would want them.....

edit: just creating food sub topics....

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#204 2015-12-28 23:36:59

RobertDyck
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Re: Crops

8. Beetroot
Beetroot is a sweet, tasty and nutritious root crop, and its leaves make a filling, robust spinach-like vegetable. In theory, sugar beet would be heavier yielding, but of little use in space where processing factories are few.

Kitchen processing:
Processing sugar beet into sugar water
Small scale farm, experimental plot 1 acre. This guy used a horse drawn plow, operated by hand. Then harvested with another plow, this time pulled by a small tractor. He used a high-end residential kitchen juicer to extract the juice (sugar water). He also built a small scale diffuser, and discusses results.
Small Scale Beet Sugar Production Methods

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#205 2015-12-29 09:11:51

RobertDyck
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Re: Crops

The second link ends by saying the sugar they made is not saleable. One argument he made was the pump is useful as animal feed. Many people who raise horses will not feed them pump from GMO sugar beets, and the only non-GMO pump is imported from Europe. That's expensive. So a farm that grows its own will produce quality pulp to feed their horses. However, if you can't sell the sugar you may as well feed the animals whole beets. He also said he made a small diffuser, which did work. Ok, so the keys to making quality sugar is to start with quality sugar beets, not fodder beets or some other variety. Yield per acre doesn't matter if the product cannot be sold. Or used on Mars by crew. The other key is to use a real diffuser, not a vegetable juicer. Industrial process to make sugar from beets:
fai9003007.png
sugar-rys-typical-layout-in-sugar-beet-diffuser-process.png
The diffuser uses sliced sugar beets, not crushed or juiced. It's then put in an auger, the auger pushes beet slices in one direction while hot water flows in the opposite direction. The result extracts sugar from the beets without too much "beet flavour". The flow diagram shows a "pulp press", which implies the juicer should have worked. Perhaps post pressing is important. That post processing invovles "liming" which means adding lime (calcium carbonate) to remove beet flavour. Precipitate then has to settle out. The flow diagram then lists "carbonating" which means adding CO2 gas under pressure. Note these post-processing steps are the same for cane sugar. The resulting syrup is then evaporated to make powdered sugar.

You can panic, but if you list all the steps to make bread from flour, the result looks just as complicated. A commercial bakery has a lot of specialized equipment, a household bread maker is a lot simpler. Similarly this process can be scaled down.

One trick:you can't boil syrup, that would burn the sugar, converting it into caramel if not just simply burnt. So syrup is dried under vacuum. That's because water boils a lower temperature at reduce pressure (partial vacuum). Candy makers use this all the time, it allows boiling hard sugar candy dry without burning. I'm sure industrial processes use fancy equipment, but there is a simpler way. Put your hot syrup in a sealed container, with a hose attached. A laboratory glass flask with a rubber stopper will do, but make sure you can get the sugar out when you're done. Instead of laboratory glassware, you could use a glass jug of some sort, and a rubber stopper with hole for a hose from your local store that sells supplies for homemade beer or wine. The hose is then connected to another container, again sealed pressure tight. You could use a laboratory round flask, or just another glass jug with another rubber stopper from the home-brew store. Heat the syrup so it's hot, but not boiling. If the syrup just came from extracting juice from sugar beets, it'll already been hot. Then hold snow against the second container. That will cause water vapour to condense. Be careful to ensure the container with syrup remains hot, while the second container is chilled with snow. The syrup will boil, even through it isn't hot enough to boil, at least not hot enough at normal air pressure. Condensing vapour in the second container will reduce pressure, that pressure reduction is enough to cause hot (but not boiling) water to, well, boil. Candy makers use this trick to boil syrup dry to make hard candy.

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#206 2015-12-29 19:00:12

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Crops

I don't doubt it can be done in a small scale way with limited resource expenditure - but you could say that about a lot of food processing.  Surely the early colonists are just going to be way too busy dealing with the essentials of life (secruing water supply, energy production, mining, construction, manufacture and basic food production) to get bogged down in processing relatively small amounts of food.  Getting your sugars from fruits and vegetables (i.e. bound up with other nutrients) is known to be a healthy way of eating.  Why not get them that way?

RobertDyck wrote:

8. Beetroot
Beetroot is a sweet, tasty and nutritious root crop, and its leaves make a filling, robust spinach-like vegetable. In theory, sugar beet would be heavier yielding, but of little use in space where processing factories are few.

Kitchen processing:
Processing sugar beet into sugar water
Small scale farm, experimental plot 1 acre. This guy used a horse drawn plow, operated by hand. Then harvested with another plow, this time pulled by a small tractor. He used a high-end residential kitchen juicer to extract the juice (sugar water). He also built a small scale diffuser, and discusses results.
Small Scale Beet Sugar Production Methods


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#207 2015-12-29 19:22:47

louis
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Posts: 7,208

Re: Crops

Lest we forget: crops aren't all about food.

I'd like to fly the flag for bamboo -

"Bamboos are the fastest-growing plants in the world, due to a unique rhizome-dependent system. Certain species of bamboo can grow 91 cm (3 ft) within a 24-hour period, at a rate of almost 4 cm (1.5 in) an hour (a growth around 1 mm every 90 seconds, or one inch every 40 minutes). Bamboos are of notable economic and cultural significance in South Asia, Southeast Asia and East Asia, being used for building materials, as a food source, and as a versatile raw product. Bamboo has a higher compressive strength than wood, brick, or concrete and a tensile strength that rivals steel."

https://en.wikipedia.org/wiki/Bamboo

The bamboo plant has a wide range of uses including in construction.  It can be used to fashion utensils and tools, provide flooring, and make furniture. It can even be used as piping for water. 

It would be a lot easier to start producing bamboo on Mars than steel. So I would suggest that it is a serious candidate for one of the early crops. 

I've often wondered about bamboo's qualities at v. low temperatures.  Does anyone know?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#208 2016-01-02 21:45:54

SpaceNut
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Re: Crops

There will be lots of crops that we will want on Mars beyond the small list that I have in the other post.

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#209 2016-04-21 14:32:02

RobertDyck
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Re: Crops

A vegan friend just posted a short video on Facebook.
Six Simple Vegan Swaps
For me the interesting on is cheese. This company has a vegan cheese substitute...
Daiya_Shreds-US_3D_Cheddar_500x500.jpg
Ingredients...(comments are theirs)

Filtered water, tapioca flour, expeller pressed non-GMO canola and/or safflower oil, coconut oil, pea protein, salt, inactive yeast, vegan natural flavours, vegetable glycerin, xanthan gum, yeast extract, citric acid (vegan, for flavour), annatto (for colour), titanium dioxide (a naturally occurring mineral).

The last one is white colour. Do we need white colour in food?

A couple other cheese substitutes...
Chao slices
Vegan gourmet

The video also mentions Just Mayo.
hamptoncreek-justmayo16ozjar.jpg?v=1439162249
Mayonnaise is normally egg white and vinegar. This one...

Canola Oil, Water, White Vinegar, 2% or less of the following: Organic Sugar, Salt, Pea Protein, Spices, Modified Food Starch, Lemon Juice Concentrate, Fruit and Vegetable Juice (color), Calcium Disodium EDTA (to preserve freshness).

And ice cream...
ca-coco-yogurt-plain-2.png

ORGANIC COCONUT MILK (WATER, ORGANIC COCONUT CREAM), CHICORY ROOT EXTRACT, ORGANIC DRIED CANE SYRUP, RICE STARCH, PECTIN, TAPIOCA DEXTROSE, ALGIN (KELP EXTRACT), MAGNESIUM PHOSPHATE, TRICALCIUM PHOSPHATE, PEA PROTEIN, LOCUST BEAN GUM, LIVE CULTURES, GUAR GUM, CARRAGEENAN, MONK FRUIT EXTRACT.

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#210 2016-04-21 18:23:39

SpaceNut
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From: New Hampshire
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Re: Crops

Not sure how many coconuts will be grown on mars but if it tastes as good as the real thing then its a go....
Mayo seems ok but its not much of an eggs salad mix if there are no eggs or tuna fish or chopped ham ect... to mix in with it sure we could have a pasta with vegeies for sure....but how good will as vegan cheese substitute pizza be....

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#211 2016-04-21 19:03:38

RobertDyck
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Re: Crops

You're right about the coconuts. Still think it won't be practical to keep livestock for a very long time. There's a segment of the population that will like a planet that's pure vegan. But my point is pure efficiency.

Age is catching up with me, and had an extremely low income for the past few years. That's why I haven't been able to make it to Mars Society conventions. My diet isn't the best. Developed a bald spot this year, but do have some hair there. Noticed length of stubble varies. Ate a few meat sandwiches Tuesday. Noticed stubble is actually growing hair today. Looks like diet affects hair growth.

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#212 2016-04-21 20:10:04

SpaceNut
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Re: Crops

Age does do that and income does effect our health to a great extent....I do agree about livestock being at least a decade down the road after first mission...as we will need to re-estate to grow what they will feed on before we can feed on them...We will be able to bring some meat products in dried, frozen and cooked plus canned but after that we are definetly waiting until we can grow what we want to eat all the way....
Which brings me back to what we bring once empty needs to be repurposed into giving man that leg up for the next revisit to the same site for further mans ability to stay....

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#213 2016-04-22 16:49:05

SpaceNut
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Re: Crops

What we do need is a menu of foods that are planned to be eatten from what we bring so that we can counter plan a diet supplement of green plants to go with it which we can grow in any available space.....

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#214 2016-04-22 17:17:00

RobertDyck
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Re: Crops

Reading about hair loss...
vitamin A: carrots - growth of cells & tissues
vitamin B6 B12 & folic acid: meat - hemoglobin to carry oxygen
vitamin C: orange - collagen
zinc: seafood, poultry, mussels, shrimp and oysters. Whole-grain products, nuts, seeds and legumes contain zinc, but in a form that is less absorbable by the body. - cell reproduction, tissue growth & repair, oil production
protein
water

Last edited by RobertDyck (2016-04-22 17:17:12)

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#215 2016-04-22 18:31:58

SpaceNut
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Re: Crops

A general vitamin will get most of these deficiencies under control...but natural source as better....

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#216 2016-04-22 23:30:28

IanM
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Re: Crops

According to the NIH, an adult man needs 90 mg of Vitamin C a day, and an adult woman 75 mg (https://ods.od.nih.gov/factsheets/VitaminC-Consumer/#h2). Assuming we have a colony of 100 men for the case of defensive pessimism, this translates to 900 mg/day, or 328.5 g per Earth year. Two kiwi fruits have around 137.2 mg of Vitamin C (http://www.health.com/health/gallery/0, … 12,00.html),resulting in 4,789 kiwis being needed to supply the colony for a year (this is still more efficient than oranges, which have only 69.7 mg of Vitamin C per serving, per the above source). Kiwi vines in the hardiest conditions, such as Mars most likely, produce ~20 lb of the fruit (http://www.rodalesorganiclife.com/garde … wing-guide), each of which is around 2.6 oz (http://www.livestrong.com/article/29953 … iwi-fruit/), thus producing 123 fruits. This results in the necessity of around 40 vines needed, each taking 200 sq. ft., ultimately consuming a total of 8,000 sq. ft., or slightly less than a fifth of an acre.

It takes a vine roughly 3 years after planting to bear fruit (http://content.libraries.wsu.edu/index. … pnw507.pdf), so assuming the vines are planted simultaneously after the colonists land, the colonists will need 985.5 g, almost a kilogram, or roughly 2 lb 3oz, of Vitamin C via supplements. Such Vitamin C would most likely be shipped in the form of a multivitamin on the same rocket as the colonists and appropriately rationed.


The Earth is the cradle of the mind, but one cannot live in a cradle forever. -Paraphrased from Tsiolkovsky

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#217 2016-04-23 19:32:20

SpaceNut
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Re: Crops

Well that per person requirement and quantity are some on the numbers but the one that is the minus is the 3 years until we can get real food...that one we will need to make use of a shipment of dried, canned and anyother method of preserving them until we can have fresh....

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#218 2016-04-23 21:18:48

IanM
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Re: Crops

I'm not too much an expert of Kiwis, but perhaps we can start growing them on Earth, and put them in a state of suspended animation on the spaceship, and then continue their growth on Mars to speed it up, though that might be too theoretical at this point.


The Earth is the cradle of the mind, but one cannot live in a cradle forever. -Paraphrased from Tsiolkovsky

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#219 2016-04-23 22:45:15

IanM
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Re: Crops

According to https://www.healthaliciousness.com/arti … amin-A.php and https://ods.od.nih.gov/factsheets/Vitam … sional/#h3, sweet potatoes are the highest-concentrated source of Vitamin A (perhaps Mark Watney was on to something with tubers!) An adult man, according to the NIH, needs 900 mcg/day, leading to 100 adult men needing 90 mg per day or 32.85 g per year. Sweet potatoes offer 1,403 mcg/day per serving, leading to 23,415 servings per year of sweet potatoes for a colony of 100. There is 1 sweet potato per serving (https://www.whatscooking.fns.usda.gov/s … 202012.pdf), so that means a 23,415 sweet potatoes are needed to feed 100 in a year. The Beauregard cultivar yields 100 plants per 100 ft of row (https://www.uaex.edu/publications/PDF/F … A-6018.pdf), and with each row having a row of 1 foot, leads to 1 plant per square foot. This leads to 23,415 square feet, or 0.54 acres of sweet potatoes to feed our citizens.

I have not read anything about any time of maturity of the plant other than the normal 90-110 day growing season despite it being a perennial plant, so I assume that a further boon to it is the ability to grow and consume it right in the first season the colonists are there.


The Earth is the cradle of the mind, but one cannot live in a cradle forever. -Paraphrased from Tsiolkovsky

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#220 2016-04-24 05:34:45

Tom Kalbfus
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Re: Crops

SpaceNut wrote:

Age does do that and income does effect our health to a great extent....I do agree about livestock being at least a decade down the road after first mission...as we will need to re-estate to grow what they will feed on before we can feed on them...We will be able to bring some meat products in dried, frozen and cooked plus canned but after that we are definetly waiting until we can grow what we want to eat all the way....
Which brings me back to what we bring once empty needs to be repurposed into giving man that leg up for the next revisit to the same site for further mans ability to stay....

No need to dry food. If you bury a food container underground on Mars, the food inside will stay frozen until it is dug up again, as the average temperature on Mars is below freezing. One can store a lot of meat products on Mars. Transporting food to Mars is cheaper than transporting people. Food doesn't need a life support system, food, after it has been killed, doesn't need to be fed. No recycling of oxygen and water is required to keep food frozen on the way to Mars.

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#221 2016-04-24 09:11:24

SpaceNut
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Re: Crops

With 6 months plus to mars even if frozen just prior to mars journey start then getting to the surface any meat will have reached its safe to consume.

Fresh to frozen chart

Refrigerator: A Food Spoilage Chart
http://www.foodsafety.gov/keep/charts/storagetimes.html
http://www.fsis.usda.gov/wps/portal/fsi … y/CT_Index

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#222 2016-04-24 10:37:31

GW Johnson
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Re: Crops

How about that mammoth meat the Russians found and cooked and ate?  It was frozen in the ground (permafrost) for tens of thousands of years.  Bare,  not wrapped in any way. 

There is a vast difference between a use-by date and an expected date of spoilage.  Use-by is usually driven by loss of some flavor.  Has nothing to do with spoilage or nutrition content.  In point of fact,  there is no spoilage in deep freeze.  Bacteria cannot grow at -10 F or colder. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#223 2016-04-24 10:44:15

RobertDyck
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Re: Crops

Shuttle carried dehydrated or dry food. By "dry food" I mean crackers, or other foods that naturally do not have significant water, and do not require rehydration. Beef jerky is normally eaten without rehydration, so that is "dry" meat. Shuttle had a galley with a rehydration port. That provided hot water to fill a bag of dehydrated food. Shuttle used a hydrogen fuel cell for power, so produced copious quantities of water as a byproduct. That made dehydrated food very efficient. The station uses solar arrays for power, and recycles oxygen and water. Recycling is not 100% efficient, and since water electrolysis is part of the system, losses to oxygen are replenished at the expense of water. So they have to send water every so often to replenish water. This means dehydrated food is not efficient on ISS, they send a lot more whole food. Rather than send dehydrated food and water, why not send wet food and that much less water? Same launch mass. But wet food generally has much shorter storage life.

I've posted this a couple times before, but apparently have to again. Mountain House: dehydrated food for hiking, climbing, camping

Our foods have the longest proven shelf life in the industry. Food sold in our iconic blue pouches have a shelf life of 12+ years. Food in our gallon-sized #10 Cans will last 25+ years. This means our food will taste virtually indistinguishable from new production for the times indicated.

They taste tested food that was 30 years old; it was "still quite tasty", although they don't claim it tasted the same as new food. Still, 12+ years is more than enough for a Mars mission. And this uses the same technology as Shuttle food. Their food is packaged in paper pouches with aluminum lining, NASA uses plastic. The plastic pouch has a moulded attachment for a hose for hot water. In zero-G you want to contain the water. For camping, you can just rip open a paper pouch and pour in boiling hot water, gravity will keep the hot water in place. No gravity on Shuttle or ISS, so plastic makes more sense. One key feature is the aluminum liner blocks all moisture and oxygen. The plastic you choose must also block moisture and oxygen. There are several plastics that will do that. The pharmaceutical industry uses Alcar, a brand name of PCTFE. It's the most impermeable to moisture of any polymer known, and highly impermeable to oxygen. Saran is more impermeable to oxygen, but not so much to moisture, so blister packs for pills typically have a very thin layer of Aclar, plus a layer of Saran, plus a layer of cheap plastic that provides strength. Aclar is strong but slightly expensive, so for cost they want to keep that is thin as possible. I'm not sure Saran could withstand the heat of hot water, but Aclar is highly impermeable to oxygen itself, and there are other polymers you could use. I'm sure NASA could come up with a plastic "sandwich" that works as well as aluminized paper.

One key to long term storage is to keep it dry. Dry pasta can be stored for years. Dry flour. Many dry foods. But you have to cook them.

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#224 2016-04-24 12:05:20

IanM
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Re: Crops

Apparently, given SpaceNut's chart, it seems like Martians will be eating a lot of poultry! That would be a decent source of Zinc, at least.


The Earth is the cradle of the mind, but one cannot live in a cradle forever. -Paraphrased from Tsiolkovsky

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#225 2016-04-24 12:21:09

RobertDyck
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Re: Crops

This discussion thread is about growing food for an early permanent settlement. Perhaps the first permanent Mars settlers. I don't think we need stored meat until we have livestock, we can grow a vegan diet. My recent obsession these last few months is hair loss, because I've developed a (mostly) bald spot. There's still some hair there, but looks like a bald spot. We don't need to design an entire planet to deal with an issue that I personally developed these last few months. But to make it somewhat relevant, varying hair growth hints that my condition is due to malnutrition. I've been unemployed far too long; I have a home business and some casual employment, but income is ridiculous. Most of my groceries come from a food bank. Just 6 years ago I was proud that I never accepted food from a food bank, I always earned enough to buy my own groceries; but these last few years I've had to. This is Mars related because it highlights the need for good nutrition.

I have argued that Mars will be vegan for many years, not for any philosophical reason, but just because it's practical. Most people here agree. So is one article: Vegan Health - Zinc

Phytates, which are commonly found in plant foods, can reduce zinc absorption, and some researchers have suggested that this increases the zinc needs of vegetarians by up to 50%.

Symptoms of zinc deficiency include poor growth and delayed sexual maturation in children, poor wound healing, hair loss, impaired immune function, and dermatitis (especially around body orifices).

They have a table of zinc in food. Most are things I can't afford, but I have lots of oatmeal. I typically have one bowl of oatmeal for breakfast, 1/3 cup oatmeal + 2/3 cup water. It's cheap, someone gave me a box with a couple bags, I get some from the food bank every so often, and a bag in the package from the Christmas Cheer Board. Perhaps I should eat more.

There's a donation box at major grocery stores; that stuff does show up at food banks, but there's very little of that. Most of what the food bank offers is "cast off". Fresh produce that's close to spoiling, eat right away or it'll spoil. Food bank provides a package once every 2nd week, but any fresh produce certainly won't last that long. There's canned food, dented or label applied upside-down, but still sealed. Bread beyond day-old; rather than throw it out, one grocery store donates to the food bank I use. This isn't city-wide, just something special that one food bank arranged. Once every few months there are pastries, but everything is beyond day-old. There are unusual foods that grocery store bought but didn't sell. And a major local grocery wholesaler provides bulk fresh potatoes, delivered to "Winnipeg Harvest" who provides food to all food banks throughout the city. Potatoes come in a "gaylord", a shipping pallet with a cardboard box that completely covers the pallet, and as high as the pallet is wide. It has to be moved by forklift. It's repackaged for food banks in large bags, then each food bank repackages in bread bags or ice bags or Subway sandwich bags. So you get about 5 pounds every second week. You can get odd things like squash you never heard of and don't know how to cook. Looking up what this stuff is and how to cook it can be an education and adventure in cooking.

When I get some money, one "treat" I often get for myself is a can of oysters. Some family members think that's strange, but they taste so good! It's only $1.69 for a can, and so good! Now I think I know why, I'm deficient in those nutrients: oil, protein, and zinc.

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