The folks who sell carbon monoxide monitors use the phrase "a-colorless-odorless-gas-that-can-kill-you-in-your-sleep" as if it were one word. I guess they use it often enough that it is one word to them. In fact people do die from carbon monoxide, around 500 every year. A sign of monoxide poisoning in the emergency department is an unconscious patient with cherry red lips. Carbon monoxide poisons by latching tightly to hemoglobin, preventing this protein from carrying out its function of binding oxygen. The bound carbon monixide produces carboxyhemoglobin instead of oxyhemoglobin. Carboxy hemoglobin is bright red, like oxyhemoglobin but it stays bound even in venous blood, which is normally darker and is what you see through the mucous membranes of the lips. Now the redness of carboxyhemoglobin has become a matter for Congress:
Retailers and manufacturers of meat products have been called on to provide information on their practice of packing fresh meat in carbon monoxide.According to Representatives John Dingell, Chairman of the Committee on Energy and Commerce, and Bart Stupak, Chairman of the Subcommittee on Oversight and Investigations, this method poses a public health risk as it disguises the spoilage of meat.
Dingell and Stupak this week sent letters companies including Cargill, Tyson Foods and Safeway Stores, requesting them to respond to inquiries on their use of this method.
"American consumers deserve to know that when they purchase food that looks fresh and safe, it actually is," said Dingell. (Food Navigator)
It's all about shelf life, you see. That's the function of modified atmosphere packaging (MAP), where the meat within the package is sealed with a low oxygen mix of carbon monoxide, nitrogen and carbon dioxide. How much does it extend shelf life? Up to 15 days. Fifteen days! But the carbon monoxide doesn't just extend the shelf life. It makes the meat look fresher (redder), too. That's the positive spin. The not-so-positive spin is that it masks spoilage. US packers aren't the only ones to use MAP. So do Chinese exporters.
You can't sell MAP packaged meat in the EU, but in 2004 the Bush Food and Drug Administration said it's OK for US consumers.
Lucky us.
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Hey-I teach this one in biochem class. CO binding hemoglobin (or myoglobin) is undetectable by a normal pulse-ox (finger clippy thing), because it uses infrared light to detect saturation of blood by oxygen. But CO-hemoglobin looks just as red as oxy-hemoglobin to it, so your hypoxic patient looks just fine by the pulse ox. Blood-gas machines use more wavelengths of light, and can tell the difference, as the electronic state isn't quite the same for the two.... Fun stuff...
But for the meat-that's just gross. Glad to be a ovo-pisco-lacto vegetarian.
15 days? That is nothing! Treat it with nitric oxide gas (as occurs in nitrite curing which forms nitrosyl-heme) and the shelf life can be 10 years or more.
http://www.ibiblio.org/uncpress/features/cookbooks/voltz_country_excerp…
Nitrosyl-heme has a characterist red color too, slightly different than carboxy heme and slightly different than oxy heme and slightly different than met-heme (Fe3+ instead of Fe2+).
But the red in meat is from myoglobin, not hemoglobin (both of which are heme proteins).
daedalus2u: you are right about meat, but the cherry red lips in CO poisoning is from carboxyhemoglobin. The use of nitrites in curing both affects color, as you note, and also has an anti-botulism effect. The AMI claims the use of MAP also has anti pathogen effects, but I'm not sure how much support there is for this. A couple of experiments with E. coli isn't quite conclusive in my mind.
The US government is not going to backslide on this. The FDA has sold out worse than crack whores. Expect more of the same and worse. What's holding worse back? Give them time, give them time.
I have more respect for crack whores.
I honestly do not see what the big deal is about this. this practice will reduce the amount of food wasted. Having taken meat science courses in several land grant universities, the professors always advised students to only purchase meat that was out of date and discounted as there was no reduction in eating quality or safety, just a brown color due to met-myoglobin. In fact, whole muscle cuts such as steaks or roasts are more tender, the further away from when the animal was killed. Most people who raise their own meat, let beef carcasses age for 21 days before freezing the meat for storage.
Mike: Maybe your meat science profs were a little too close to the meat packers?
I'm flashing back to the scene in SHOGUN where the gross European washashore hangs his newkilled pheasant to "age properly"... i.e., until the advancing rot causes the carcass to separate from head. The Japanese freshness advocates didn't look like they were appreciating that lesson, for some reason.
Gentle People,
I know it is early in the discussion, but can you give some factual information to us? My questions:
Is the carbon monoxide used to treat the meat, of itself, poisonous for human consumption? I have been avoiding so-labeled meat because it sounds nasty and unappetizing, but there are no news reports of people actually becoming ill from this method of meat preservation, are there?
Wouldn't proper handling and cooking of the meat kill all harmful bacterial in the meat anyway? Local butchers sell aged beef at a premium price. It is very tasty and has not been reported to cause illnesses in our community.
Perhaps the American preference for red, bloody, "fresh" meat rather than dark, "old date" meat is the result of advertising, urban mythology, or a result of "sell by" and "use by" dates seen on packaging. I throw away some out-dated products simply because I'm not sure and I don't want to take any chances. (As an aside, I volunteer at a local food pantry. Occasionally when I discard an out-dated food, other volunteers, who grew up during the depression, will put it back on the shelf. I throw it away a second time.)
You can visit the FDA website and get guidelines for food dates, but it is still hard to throw away food that looks perfectly good.
I have always felt that kosher meats are most healthy and trustworthy. Does anyone in your group know how meats intended to be designated kosher are handled during processing today?
Thank You,
Library Lady