@igor: Here’s a thread from ~18 months ago that ends up exploring this point after a 3rd grade teacher proposes teaching a physics simplification to his class. Push versus pull, as forces, in sports - Factual Questions - Straight Dope Message Board
The term “lies to children” seems to be the educator’s term of art. Or at least the education detractor’s term of art.
Lime juice can be used instead of heat to render meat safe.
The resulting product is called ceviche, or Carne Apache if it is made with beef.
Quoting myself for context.
See also Lie-to-children - Wikipedia
What about freezing like sushi?
Ammonia is or was used to treat lean finely textured beef, aka pink slime. But that was intended for cooking. It would be hard to drive off the ammonia without heat.
I’m having trouble imaging how you could kill pathogens and still be left with something you’d want to eat.
Trichinosis is almost unknown among, at least American, pork. It stopped being an issue when pork producers stopped feeding pigs literal garbage.
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I’m not so sure about that. If we consider meat to be the flesh of land mammals, cooked meat wins by a landslide, based on a reasonable interpretation of this chart from XKCD.
Now, if you’re including krill and so on, that’ll certainly change the ratio a bit.
This abstract seems to imply that ultrasound can be useful in meat processing for things such as tenderization of the meat and cleaning of the processing surfaces, but not for eliminating microbial contamination; or at least the evidence for it is lacking.
http://www.sciencedirect.com/science/article/pii/S0309174015001126
Irradiation can cause rancidity in fatty acids. While this probably wouldn’t make meat unsafe to eat, it could make it taste nasty.
The usual issue with irradiated foods is that irradiation kills everything. Not just any pathogens, but the food itself. Which sounds silly, surly the food is already dead? However fruit and vegetables continue to live (after all for most of them that is their purpose - they are the progenitors of new life) and even in meat cellular processes can continue after a fashion for a very long time. Cellular machinery keeps the food in good shape, battling the forces of entropy and degradation. Usually external pathogens are also in the hunt and they will outpace the cellular machinery, such as it remains, and degrade the food. But when you irradiate the food the pathogens go as well. So the food is both sterile and dead. This means it degrades differently. You can find food that is clearly degraded from the point of view of breakdown of cellular material and structure, but is still perfectly sterile.
Cooking is a funny thing. It oes not so much involve chemical reactions as we usually think of them (not until you get to browning reactions) but rather coagulation and denaturing of proteins. The best example being cooking an egg white. But meat cooks in much the same way, it is just that there is more stuff coagulating and proteins winding up into long tight strings, which results in cell disruption and the forces that make the meat shrink and expel fluid. You can “cook” meat chemically As noted above, there are many foods prepared this way. Gravlax is another not so far mentioned. Many traditional sausages are also chemically cooked/preserved.
The extreme I’m thinking of is a high power unit used to completely obliterate tissue and lyse all cells.
Don’t brush your teeth with it. 
I think that’s only effective against parasites, not bacteria.
Freezing will kill bacteria. However, to kill most bacteria reliably, you need to get to less than -4C (IIRC). Commercial home use freezers don’t get that low. Bacteria which survive freezing go dormant and revive when thawed. The best way to kill them is multiple cycles of freezing and thawing.
Most Bacteria or at least harmful ones will die at temperatures between 90C-95C. Most home cooking devices easily reach that temperature and beyond.
[QUOTE=mixdenny]
Not really, Robert, depends on where you are. One of the standard cautions for traveling abroad (to some areas) is to not drink the local water or eat uncooked veggies like salad. They can all contain bacteria that the locals have built up a resistance to. But they will wreak havoc on your gut.
On my first trip to Thailand I got a good dose of intestinal distress that lasted for weeks. I was very careful not to eat or drink anything I shouldn’t so I was puzzled as to how I got it.
Then it dawned on me, I had been drinking iced tea from street vendors. The tea itself is prepared right before your eyes from boiling water and served in a new plastic bag, so it was OK. But the ice! They just scooped it out of buckets, it seemed good, nice cube shapes, but I bet it wasn’t bottled water to begin with.
Dennis
[/QUOTE]
There is little you can do about local pathogens even if you are careful since there are many ways to ingest them. And your bodies unfamiliarity with them means that you have the pleasure of travelers diarrhea. You can get it even in a different city in your own country. My gastroenterologist tells me that the best thing you can do is wash your hands regularly. With soap and water.
One of the worst runs I had was after eating in a very upscale restaurant in NYC.
Nobody in that party fell sick except moi and they were all locals.
Maybe you mean -4F, because -4C is a pretty high temp and wouldn’t be a very good freezer at all. Right now, my freezer is at 0F, which is about -18C (and pretty standard), and the fridge at 38F, or about 3C.
No doubt there are bacteria that are killed by freezing. And even more that are killed by thawing.
But any process that doesn’t destroy the individual cells of meat, also does not destroy the single cells of single-cell organisms.
I wish they did, but people who fear radiation while knowing little about it have created a situation where irradiated meat is not available to the general public. The obstacles are psychological, not technological.
Nobody’s going to mention that meat is safe to heat until it’s approaching it’s ignition temperature?
Not entirely.
From “Effect of Ultrasound on Food Processing,” by Jordi Salazar, Juan A. Chávez, Antoni Turó, and Miguel J. García-Hernández, in Novel Food Processing: Effects on Rheological And Functional Properties, Jason Ahmed et al., Taylor and Francis:2010
This application is a promising field that relies on the ability of power ultrasound to disrupt biological cell walls through intense cavitation. However, the effectiveness of ultrasound is dependenton the type of microorganism or enzyme being treated, amplitude and frequency of the ultrasonic signal, exposure time, volume of food to be processed, and type of food. In addition, power ultrasound alone is not very effective in the destruction of microorganisms or inactivation of enzymes unless very high intensities are used and, precisely for this reason, generally ultrasound is used in conjunction with another technique such as pressure (manosonication), heat (thermosonication), or both (manothermosonication), to achieve efficient destruction of microorganisms or inactivation of enzymes. Thus, for instance, using pressure during power ultrasound treatment increases the rate of microbial inactivation in a variety of microorganisms, even at temperatures well below the boiling point of the medium. Figure 6.2 shows the effectiveness of this process at a very low temperature when pressure varies from 0 to 400 kPa. All these processes have been studied and described in depth by several researchers (Ordoñez et al. 1984; Raso et al. 1998; Mañas et al. 2000; Mañas and Pagán 2005).
So far, research has been successfully done on a great number of bacteria such as Escherichia coli, Listeria monocytogenes, Salmonella, Staphylococcus aureus, Saccharomyces cerevisiae, and others (Piyasena, Mohareb, and McKellar 2003).
Ultrasonic treatment under high pressure is another twist with different issues; on meat, as you say, ultrasound has been investigated primarily as an aid to tenderization, and results over the years have been widely disparate; its more promising applications have been on crystallization, drying, filtering, and emulsification (which brings us into other areas of loss processing, of course). There’s lots of good stuff in rapid, intense cavitation.
It’s interesting, I think, that the effects of idea of radio frequency/microwave for pasteurization began in the early 1930’s. Nowadays, due to cost and difficulties in scaling with RF, bringing some work on high-electric field (HEF) and nanosecond-length high-intensity electric field pulses (HELP).
However, the thrust of a number of modern sterilization techniques (see above citation) is “merely” to change the physical and chemical permeability of selected cell types, not to destroy them as a whole but to change their functionality.
ETA: cx to ultrasonic reply above: “… (which brings us into other areas of [del]loss[/del] food processing, of course)…”
Be careful with what you call that beef: it could cost you over a $Billion.