Do you have a cite for this? It was to my understanding that even meat left for a relatively long time will still be effectively sterile much beyond the surface. Good beef can be aged for up to 2 or 3 months, after which, the outside layer is pretty much scraped off and discarded while the inside still remains edible. I doubt this would be the case if bacteria were capable of penetrating muscle tissue.
I have never heard that they are inedible, or that they concentrate toxins in their flesh. Since I’m pretty familiar with the technical literature on vultures I’m fairly sure I would have heard something about it if it were true.
Unfortunately I’ve long since sold my meat quality text which covered this. Hopefully these wil do.
“Bacteria are the major cause of seafood spoilage. Millions of bacteria are on the surface, on the gills, and in the gut of living fish and shellfish. After harvest, bacteria invade the flesh of fish and shellfish through the gills, along blood vessels, and directly through the skin and belly cavity lining. These bacteria grow and multiply in the flesh. They produce the ‘fishy’ smelling and tasting compounds associated with old seafood. If food-poisoning bacteria are present, they can multiply and cause illness.”
http://www.safespectrum.com/applications_seafood.html
The marked organism was introduced by injection through the captive bolt aperture immediately after stunning and was subsequently detected in a wide range of derived tissues, including blood, organs, and the musculature of the entire forequarters of test animals. This was dependent on the use of high concentrations of the organism that were recovered sufficiently and rapidly to minimize the bactericidal properties of the circulatory system.
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-2672.2004.02124.x
Bacteria are far more prevalention the surface of meat, but it’s a mistake to think that they haven’t spread throughout the flesh, since the blood vessels are essentially just hollow tubes designed for cell transport.
I don’t know the answer to this question, but i’d like to point out that there is a big difference between a circulatory system under pressure and a circulatory system clogged up by dead red blood cells.
What about birds and animals that scavenge rotting corpses without getting sick? Do they have a sturdier digestive system?
SD column relating to the topic:
It makes sense, really - meat on carcasses doesn’t have a hell of a lot of time in which to really go bad, as animals and insects will find it pretty quickly and eat as much as they can, then the animals will leave it once it’s too far gone.
Not recommending anything here, but I had a roomate (whom I never did like much) who often cooked meat I’d have tossed. I know sour, and she had no problem with meat that was a step or two beyond just sour. She was never sick, so I always wondered whether it was just an iron constitution or the fact she cooked the heck out of everything.
Like Harmonix said, there are differences betwen living and dead circulatory systems. I wonder how some bacteria would pass post-mortem blood clots, for example.
And of course living animals (including seafood) have bacteria everywhere, so do you. 
And there’s a reason why cattles, chicken, and pigs are inspected before death and after death: To prevent sick animals from becoming part of the food chain. From your first link, it says that if food-poisoning bacteria are present, they may cause illness. Well, that’s what one tries to prevent with a good cattle, pig, and chicken operation, not to mention clean slaughterhouses and good inspections.
Your second link is very interesting, but not for the reason you cited. It is a paper that wants to see if it is possible for prions to move to the other parts of the animal due to the electrical stunning that animals get prior to being slaughtered. Note that the dose of bacteria they artificially give the animal after the stunning is very high (they said so), and that again, it is travelling through a still alive circulatory system.
Erm, IANAButcher, but I think the point is that blood vessels provide a ‘highway’ for bacteria to invade the muscle tissue during the process of putrefaction. There should not be any blood in the vessels of prepared meat anyway, and I guess the blood vessels will be mostly collapsed and semi-sealed due to being drained immediately after slaughter, but I would still expect the vessels to be a handy route for bacteria to grow along, enabling them to spread from the surface to the inside of the steak or whatever within a few days. Even if blood clots are present, they will just act as a handy bacterial growth medium. Therefore any toxin-producing bacteria would be able to contaminate the entire piece of meat fairly rapidly. Bear in mind that beef is hung for up to 28 days - if some nasties have gotten onto it, they have quite a bit of time to spread.
Unless it’s a huge chunk of meat, I would assume that if any part of it is spoiled, the rest of it should be regardsed as spoiled too.
As to eating spoiled meat, well, I guess it’s a novel form of russian roulette. Feel free to try it and report the results back here for our edification 
Your first quote refers to seafood which behaves very differently to meat bacteriologically.
Your second quote refers to an injection of a huge amount of bacteria into the nervous system of a still living creature with a working transport system. Your cite itself says the blood stream is bacteriacidal and only the huge amount injected was enough to show any traces in the organs. Again, such a case cannot be directly compared to a slaughtered animal with normal bacterial loads.
Yup your meat would be edible, and you probably wouldn’t even get sick if you cleaned it as recommended above. It also wouldn’t hurt to pressure cook it, boil it, or heavily salt/sugar it.
Most of the bacteria are going to be on the surface. First wash the meat thoroughly. The biggest problem with this, is that I just get grossed out by wet meat (stop it- you pervs). But, be that as it may, a good surface scrubbing should get rid of ~90% of the bacteria (don’t ask me for a cite because this is a estimate from a hand wash experiment I once did). This would include the bulk of the toxins.
There is absolutely no reason to believe that interior surfaces will be contaminated until the meat actually begins to break down, and the muscle tissue separates. This would allow bacteria and toxins to spread on to all exposed surfaces. There certainly are bacterial species which are motile, but they aren’t really scooting about in the way that a protozoa or a worm would be. They most just sit there and spread on their own slime, move by twirling their flagella, or just get bashed about by molecules and debris.
As mentioned, it’s not the bacteria, but the by-product which you need to be worried about. The toxins of many bacteria are pretty heat-stable, while the bacteria are heat-liable. However, pressure cooking, boiling, salting, and even sugaring (yech), would take care of nearly all of the toxins, so your immune system should take care of the rest.
The biggest problems with undercooked meat are not the surfaces of the meat itself. The food poisoning comes from food which is contaminated from the surfaces touched by the meat which aren’t cooked thoroughly. Think tomatoes contaminated from a cutting board, or stuffing in a turkey which isn’t brought to temp.
The reason hamburger is so dangerous is because the surface of meat, becomes ground in to be the interior of the meat. Thus unless it cooked to temp it can be dangerous. However, you must remember not everyone is even at risk for food poisoning. The young, the elderly, and the immunocompromised, are those who should be very careful.
Watch you friendly neighborhood Microbiologist. We’ll eat nearly anything. I think it one of those things where a little bit of knowledge makes you paranoid, and a whole lot of knowledge makes you careless.
OK, help me here. It looks like getting rid of the bacteria themselves is a relative snap. Oh, but those toxins …
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What does pressure cooking do to these toxins that ordinary cooking doesn’t?
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Is Blake right that the toxins really can’t be removed from the meat’s cells? Forget boiling water – what about acids? Mild ones like vinegar or citric acid? Strong ones like hydrochloric or hydroflouric (I realize that after such treatment, there’s probably no edible meat left)?
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So is it humanly possible to denature these toxins in such a way that they are benign to the body AND be left with edible meat:
Radiation?
Extreme heat/cold?
Introduction of highly reactive substances?
Introduction of bacteria that can eat the toxins and release benign waste?
Or must one give up the meat in any successful effort to neutralize the toxins?
Pressure cooking is essentially autoclaving. Because you increase the pressure, you can increase the temperature (PV=nRT) to 121°C which will denature toxins. Boiling should dilute the toxins to a point where they are at a level lower than that of toxicity (LD50), and salting/sugaring denatures toxins by altering osmotic pressure.
Sure the chemical methods you mention would denature the toxins, but you do want to eat the meat, right? I wouldn’t want to consume chemically treated meat (irradiated-no problem). I prefer to let my body deal with the toxins it’s been designed to deal with (proteins) and take my chances than to introduce completely foreign toxins
None of these are perfect methods, and I certainly am not advocating consuming rancid meat, but it was, and is, done regularly. In fact just yesterday, I saw on the evening news Somalis stealing rotten carcasses from animals for food. It was very disturbing, and potentially dangerous, as those people are very sick, and very small.
Sure. If a vinegar or lemon-juice marinade is enough to denature the toxins, then I’d assume the meat would still be edible, of course. On the other hand, if we need stronger acids, the meat would obviously be no good after treatment.
The recommendation for toxins that can’t be destroyed using high heat is Sodium Hypochlorite (NaOCl) a.k.a. bleach. Bleach kills not because of it’s pH, but because it is highly disassociative. It breaks down to highly reactive atoms and bind with the proteins.
That said, I don’t know what pH would denature the proteins. However, extremes in pH will indeed denature protein. But I would guess you would need a stronger acids (bases) than your marinades to kill the toxins.
It probably is possible, however, just like turning lead into gold, the cost of doing so far outweighs the benefit. Why spend $50 to remove toxins from a pound of beef when you can buy a fresh pound of beef for $5?
Just a thought experiment. I held out hope for the efficacy of a mildly acidic marinade, though.
Light strand, after your mention of bleach, I got to thinking “are any foodstuffs chemically basic enough to do the trick?” I sure can’t think of anything.
Getting away from acids/bases for the moment – how about a marinade of 151-proof rum or Everclear?
More to say:
There is a practical side of this discussion, too. It would be useful to know if just barely spoiled meat could be consistently made safe for consumption using ordinary kitchen items … or at least items easily and inexpensively procured at the grocery.
So far, this discussion has given me the impression that refrigerated meat a day or two past its prime can pretty much be safely reclaimed. A dip in boiling water, a scrub-down with a vegetable brush (or whatever), a thorough rinsing, an acidic marinade for good measure, follwed by a through cooking and voilà – prefectly good meat.
Now, meat that’s been sitting at room temperature on the counter for a month? Eh, no thanks.