You’re at the grocery store or visiting your local butcher and you decide to purchase some beef. On the way home, you notice some red liquid leaking out of the meat into the packaging. Those same juices can also be seen sizzling and oozing out from the meat as it’s being cooked. For those with an aversion to blood, it can make them extremely uncomfortable.
In rare cases, individuals who are susceptible to vasovagal syncope (fainting from the sight of blood) have had fainting spells due to the sight of a particularly messy batch of meats. It’s no wonder those who are extremely sensitive will swear off meat all together and become a vegetarian.
But do those individuals have a good reason to react that way? Are those crimson juices actually animal blood?
Close, But No Cigar
Nope! Those juices are definitely not blood. They are slightly related, however. Those juices are actually water, sarcoplasm and trace amounts of myoglobin. Myoglobin and sarcoplasm are proteins found in found in the muscle tissue of most vertebrates and in almost all mammals. They’re related to hemoglobin, which is the iron and oxygen-binding protein in blood. However, the only time myoglobin is found in the bloodstream is when it is released following a deep muscle injury.
Myoglobin is what gives meat its dark red color pigment. Meat that is cooked well-done is dark brown on the outside (and grey on the inside) because the iron atom is now in the +3 oxidation state, having lost its electron, and is now coordinated by a water molecule.
When shopping, retailers know that customers will always choose bright pink “fresher” meats over darker, brown meats due to the latter looking like it’s on the verge of spoiling. Having to throw away meat that is reasonably fresh and safe (but no longer pretty) is estimated to cost the industry up to a billion dollars annually. To reduce this loss, the industry discovered a clever way to help the meat retain its attractive pink color longer, much longer.
Several larger companies have begun treating their meat with nitrates and then packing & storing the product in a carbon monoxide atmosphere. The carbon monoxide gas in the package slows the discoloration of the meat. Unfortunately, this is a deceptive marketing practice as it only makes the meat look fresh. The artificially-induced pink color can remain in the meat for a very long time, up to one full year. Companies have been using this technique since early 2003.
So How To Tell If Beef is Fresh?
The easiest way to tell if meat is fresh is to always check the dates on the packages. This gives you a general idea about the meat’s freshness. The second is to feel the meat. For example, beef that is fresh will have a moist, almost soft texture. If it’s slimy or sticky, it’s beginning to spoil (or already has spoiled). Grey portions indicate the meat is in the process of spoiling, or has been frozen or refrigerated too long. If freezing caused the greyness, the meat is probably still good to eat but will have lost some of its flavor and will cook up tough. Also, be sure to smell the meat – if you smell a nutty or cardboard-like smell, the beef is spoiled.
Wu G, Wainwright LM, Poole RK (2003). “Microbial globins”. Adv. Microb. Physiol. Advances in Microbial Physiology 47: 255–310
Ordway GA, Garry DJ (September 2004). “Myoglobin: an essential hemoprotein in striated muscle“. J. Exp. Biol. 207
Washington Post (February 20, 2006). “FDA Is Urged to Ban Carbon-Monoxide-Treated Meat”
McGee H (2004). On Food and Cooking: The Science and Lore of the Kitchen. New York: Scribner. p. 148.