Naked Science Forum

General Science => General Science => Topic started by: micahj93 on 30/10/2011 06:20:40

Title: tomorrows food preservation?
Post by: micahj93 on 30/10/2011 06:20:40
Is it possible to preserve food by forcing the molecules into a dormant stage until re-activated for consumption?
Title: tomorrows food preservation?
Post by: CliffordK on 30/10/2011 08:41:57
Freezing?

Food gets "old" due to a combination of chemical and biologic decomposition.

Freezing it can hinder both processes, and in a sense, frozen is the only true "dormant" form for molecules.  Although, the electrons are still orbiting the atomic nuclei, so it is not truly dormant.

Most people keep their refrigerators at just below freezing.  One can certainly go for colder temperatures.  For example, a Helium Freezer would run at about −269°C, and would be about as close as you could get to "dormant molecules".

NASA has been worried about long-term food storage for extended space flights.  But, it would be simple enough to build a freezer module with a solar heat shield somewhat like the James Webb Space Telescope (JWST), and it would keep food essentially inert for decades. 

Of course, you could still have freeze/thaw damage.

Freeze drying is also an excellent preservation technique.  Just add water, and the food can be surprisingly flavorful, especially after a long hot hike in the woods.
Title: tomorrows food preservation?
Post by: Johann Mahne on 31/10/2011 08:58:50
Hi Clifford,
I think that NASA should use McDonald burgers as they can keep fresh on the shelf for those lengthy space trips.
http://www.dailymail.co.uk/news/article-1258913/Happy-1st-birthday-Mother-keeps-McDonalds-Happy-Meal-year--gone-off.html (http://www.dailymail.co.uk/news/article-1258913/Happy-1st-birthday-Mother-keeps-McDonalds-Happy-Meal-year--gone-off.html)
Title: tomorrows food preservation?
Post by: CliffordK on 31/10/2011 09:31:15
Hi Clifford,
I think that NASA should use McDonald burgers
I avoid FRESH McDonalds Burgers.  I'm not sure a year old burger would be too appetizing. 

There was a special I saw, perhaps a BBC special discussing NASA and food preservation. 

But, I think it was discussing something like Army MRE meals.  Some of their preserves looked pretty nasty due to chemical decomposition after a while.

Say, one chose to do a 10+ year trip to Jupiter (and back?).  I would hope that one would choose to assemble the ship in space, and have a large portion of the ship with centrifugal gravity, and another portion as a dedicated greenhouse.  One would undoubtedly develop an extremely efficient water recycling system.  Weight would be at a premium.  Thus, any "earth food" would undoubtedly be freeze dried.  Just reconstitute with recycled water. 

Combine Freeze Drying with storage at say -260°C, and the food could be preserved essentially indefinitely.

Another idea with food storage for space.

Water is essentially easy to remove and add back in.  However, perhaps one would design a system to synthesize other components too.  For example, if one could develop a method to synthesize sucrose.  Then one could remove all natural sugars from the foods.  Then add synthetic sucrose as a sweetener and caloric supplement.  One essentially already does that with many juices and other foods.
Title: tomorrows food preservation?
Post by: Geezer on 31/10/2011 17:26:05
Freeze drying is also an excellent preservation technique.  Just add water, and the food can be surprisingly flavorful, especially after a long hot hike in the woods.

Yes. Freeze dried peas used to be sold in the UK under the brand name Surprise Peas. They were actually quite good, even though they did occasionally give you wet legs.
Title: tomorrows food preservation?
Post by: CZARCAR on 31/10/2011 17:46:22
vs= is it possible to sterilize spoiled food so to make it safely edible?
Title: tomorrows food preservation?
Post by: CliffordK on 31/10/2011 18:05:19
vs= is it possible to sterilize spoiled food so to make it safely edible?

I would imagine so.
You would have to denature any toxins.
Without getting the food hot enough to make charcoal.

A pressure cooker might be sufficient.
Title: tomorrows food preservation?
Post by: CZARCAR on 31/10/2011 20:20:03
Wonder what shitsoup tastes like & if acceptably spiced can it be beneficial
Title: tomorrows food preservation?
Post by: Bored chemist on 31/10/2011 20:31:18
Some toxins are sufficiently thermally stable that you wouldn't be able to destroy them this way (practically, at any rate and who would want to try?)
Title: tomorrows food preservation?
Post by: CZARCAR on 31/10/2011 22:14:50
Some toxins are sufficiently thermally stable that you wouldn't be able to destroy them this way (practically, at any rate and who would want to try?)
dogs eat sh1t & maybe babies? why?
Title: tomorrows food preservation?
Post by: CliffordK on 01/11/2011 00:05:28
Some toxins are sufficiently thermally stable that you wouldn't be able to destroy them this way (practically, at any rate and who would want to try?)
I suppose the question is what toxins.

Cyanide & derivatives would be heat stable.

Staph Aureus toxin.
Botox
E-Coli Toxin (I think)
Are not heat stable.

Likewise, the bacteria and fungi are relatively easy to kill off.

While Mad Cow disease is relatively heat stable, it isn't concentrated by decomposition.

Heavy Metals wouldn't be in the decomposed food if it wasn't in it before decomposition (unless leached from the container).

So, while cyanide is produced in nature...  is it produced by decomposition?
Title: tomorrows food preservation?
Post by: Johann Mahne on 01/11/2011 04:42:25
Quote
I avoid FRESH McDonalds Burgers.  I'm not sure a year old burger would be too appetizing.
According to the grand mother who conducted the test, there were no flies or insects attracted to the year old burger. So they did not find it appetizing either.
  Well i geuss it's nice to know that ants and mice won't be eating your old burgers.
Anyway, the astronauts could use the burgers for emergency rocket fuel if they had the right grease burners on board.  [:D]
Title: tomorrows food preservation?
Post by: Don_1 on 01/11/2011 12:59:03
I recall many years ago there was a deal of excitement over fresh food preservation by irradiation. I think the claims of everlasting tomatoes were somewhat overstated. Although legal in the UK, I don't think it caught on because of fears of consuming radioactive food, even though the dose of radiation was tiny.

Take a look at this from the UK Food Standards Agency (http://www.food.gov.uk/safereating/rad_in_food/irradfoodqa/)
Title: tomorrows food preservation?
Post by: CliffordK on 01/11/2011 18:28:45
There is also a Wikipedia Page on Food Irradiation (http://en.wikipedia.org/wiki/Food_irradiation).  I thought the practice was widespread, but apparently still in the experimental stage.

One of the uses of food irradiation is the prevention of the spread of invasive species...  and with that in mind, I would imagine it will become far more common.  Furthermore, it may increase the shelf life of certain foods.
Title: tomorrows food preservation?
Post by: Don_1 on 02/11/2011 15:32:07
I'm not so sure that it was found to be cost effective. I do recall wild promises of fruits which would last months on end, but the reality was nowhere near the expectation. Refrigeration and freezing are far cheaper, acceptable to the public and effective.

I don't see a viable substitute coming along for quite a while. Perhaps preservation will begin with the seed. GM crops which will have a long shelf life. But this too would require much convincing of the public before it would be acceptable. Carefully protected trials would need to span many years and would need to be 100% safe for the environment before being grown commercially.
Title: tomorrows food preservation?
Post by: Bored chemist on 02/11/2011 19:22:08
One of the issues with irradiating food is that you can take  second rate, contaminated stuff, zap it to kill the bacteria then repackage it and sell it on as a better grade.

The public perception of irradiation is not positive (I can see pros and cons to it) so it's not used much.
Title: tomorrows food preservation?
Post by: CZARCAR on 02/11/2011 19:33:59
One of the issues with irradiating food is that you can take  second rate, contaminated stuff, zap it to kill the bacteria then repackage it and sell it on as a better grade.

The public perception of irradiation is not positive (I can see pros and cons to it) so it's not used much.
so i can eat reradiated food safely? or whats the probability of contamination & resultant infection?






















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Title: tomorrows food preservation?
Post by: CliffordK on 03/11/2011 08:20:25
Perhaps they can convert nuclear waste repositories to food irradiation facilities. 

Kind of like killing two birds with one stone [:-\]

There is an aspect of radiation being transferred from one material to another.  But, I believe it requires direct contact.  It would not take much of a barrier to prevent Alpha and Beta from being emitted, and one could be left with pure gamma emissions.
Title: tomorrows food preservation?
Post by: Don_1 on 03/11/2011 09:09:37
One of the issues with irradiating food is that you can take  second rate, contaminated stuff, zap it to kill the bacteria then repackage it and sell it on as a better grade.


Yes BC, I do recall that was another issue of some concern.