A few evenings ago, I was consulted by a friend of mine about the color of meat and how to tell if it’s bad. She sent me this photo….

Dark MeatBack story… this woman bought these steaks, opened them up, turned them over, and found this…. She assumed they were bad and threw them out! She then went ahead to post the photo on Facebook with a comment about how upset she was her steaks were bad. Although I don’t know this woman, I wish I would have been able to let this woman know her steaks were perfectly fine. And it makes me sad that nobody on those 20 comments told her that either. 

Huh!? Brown meat!? That’s right. Brown meat is OKAY to eat.. So what makes meat red in the first place? The most common answer people give me is blood. Well I hate to break it to you but there is actually no blood in muscles. All the blood is removed from the animal when it is slaughtered. That red liquid you see is actually water mixing with a protein that gives meat its red color, myoglobin.  Myoglobin is a protein that stores oxygen for aerobic metabolism in the muscle. All mammals contain this protein in their meat tissues and is very similar to hemoglobin which stores oxygen in our red blood cells. This protein is normally a dark grayish-purple but when it comes in contact with oxygen, it becomes oxymyoglobin and reacts by turning a deep red color. That is why most of the meat we see has a bright red color.

But this color can vary, as we have seen before, from light red to an intense red to an almost purple color. Color in meat can change depending on the age of the animal, the species, sex, diet, and even the exercise it gets. The meat from older animals will be darker in color because the myoglobin level increases with as animals age. Exercised muscles are always darker in color. Because muscles differ greatly in activity, their oxygen demand varies which in turn means the same animal can have variations of color in its muscles. Also myoglobin levels vary by species which is why beef has more of a red color than pork or lamb.  So why does meat turn brown?

Both myoglobin and oxymyoglobin have the ability to lose their oxidation which results in a brown color called metmyoglobin. This essentially means that meat can turn from a bright red color (which many associate with fresh) to a brown color from a lack of oxygen. Meat can also turn brown if any sort of contamination that would cause a chemical reaction comes in contact with it. For example, cure (sodium nitrite) turns raw meat a brownish-grey color (think of a cured, uncooked salami) if it comes in direct contact with a meat surface, but if that same meat is then heated, the sodium nitrite turns the meat a pinkish color (much like ham). In order for meat to maintain that bright red color we are familiar with, oxygen must be available at a sufficient concentration. That is why grocery stores utilize a small film over their products versus a vacuum package. Browning of meat can also occur with meat that has been chilled for a long period of time (about 5 days), ie: taken home from the grocery store and placed in your fridge for some time. This happens because as meat is chilled/frozen for long periods of time, enzyme activity decreases so the myoglobin and oxygen quit mixing together to keep meat that bright red color.

Browning of meat can also occur when oxygen partial pressure is low or basically when meat is stacked on top of one another. This is more than likely the case from the photo above. This is also the reason why your ground beef from the store may be red on the outside but brown on the inside. Oxygen can’t readily make its way through or penetrate the ground beef so it begins to lose its red color on the inside after time. The changing from red to brown and even the purplish color to red occurs quite easily in meat, the reverse is much difficult. Once meat has browned, it is hard to get it enough oxygen to reverse the process. Also, this same process is the reason meat does indeed turn brown when you cook it. But once meat is cooked, it denatures the proteins so there is really no going back! All of the protein is not affected at the same time which is why you get different variations of a reddish color at different temperature points. Basically this is what gives us rare, medium rare, medium, well done, etc. Those colors associated with meat temperatures are basically denatured metmyoglobin!

So we’ve established once meat turns brown, it’s hard for it to turn back to that red color. One myth I see commonly brought up is that old meat is dyed red. This is not anything any of us in the meat industry have heard of nor have we found information to supply this so-called practice. Since we are dealing with an enzymatic reaction here, I don’t think any dye could possibly work as effectively as the reaction itself. When you see red meat in the grocery store, it’s because it is a. actually fresh  and b. allowed oxygen to keep it that red color.

So if color isn’t an indicator of spoiled meat, what is…? The number one indicator of spoiled meat is in fact smell. An off odor will be prevalent to your senses and the most effective way to diagnose spoiled meat. Another indicator of spoiled meat is tacky or sticky to the touch. Slimy meat (not juicy) is also a great indicator of spoilage. This especially occurs if meat has been temperature abused. Raw meat that has been heated up (not cooked) and then re-cooled will often times become sticky or tacky along with possibly a color change. Use these three factors in diagnosing spoiled meat: does it smell, is it sticky, AND does it have color change? If all three or at least two of three are present (even with NO color change) than it’s probably alright to toss it rather than risk getting sick.

So if you happen to open up a package of meat looking like the photo above, please don’t throw it away simply because of its color. Use the three indicators given to diagnose if it’s spoiled or not. If it is not spoiled, feel free to indulge without worry!

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For more information on this topic, visit these sources:

The Color of Meat & Poultry from USDA

Meat Color from University of Saskatchewan

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This Post Has 27 Comments

  1. Janice aka JPlovesCOTTON

    GREAT blog post! I hope a lot of folks read it. I’m lucky in that my mom was the daughter of a butcher so she taught me not to worry about color changing as much as smelling. One thing with that though is you need to know what should smell like generally. Seems a small thing but touch & smell are all relative.

    1. jenniferdewey

      Thanks Janice! I am surprised by the number of people who either bring us meat or call us to ask about meat being spoiled. I, too, hope this post sheds some light on that! And you are right that smell and touch are relative, but they are the number one indicators we use to diagnose. Like anything else, if you aren’t sure, it is always okay to get a second opinion! ;) Afterall someones sniffer may be a little better than someone else’s!

  2. Angelo Ibleto

    It amazing to me the. in a meat eating Country as america is, so many consumer’s minds are still in limbo about knowing what is good or bad in the meat’s world. What is looking bad, (in this case) actually is better. I changed my approach long time ago with impossible costumers the, have proofed they don’t listen. If the face cut of the N.Y.. strip is dark, I reface it with cutting off a thin slice for myself. I sell only the best, it is mandatory the my dry rub, (Angelo’s Magic) is on. I give the costumers a 3X5 instruction card telling them how to prepared it. I think it is more then 2 years since a costumer came back telling me that steak was not too good. I looked him strait in the eye and told him. ” If it was not the best steak you ever eaten is, because you SCREW it up..
    Moregarlic @aol.com http://www.angelossmokehouse.com Have a good day.

    1. jenniferdewey

      Angelo- I miss you and your no-BS attitude!! It’s also amazing to me how many people lack knowledge when it comes to meat which is why I do what I do. I hope that my contributions hopefully and at least educate one person out there, if not many! :)

  3. Angelo Ibleto

    I have missed seeing you at the convention in Davis last month. I printed two copies, I keep one in Petaluma and one in Sonoma deli. I feel it is good have the information’s in black and white otherwise there is always around the smart ass the ask “how you know that” About the no BS attitude, you are right. At my age, armed with proof the I give every day 100% of whatever I do in the business, the patient fuse is getting shorter by the days so, I make short and sweet. You want the best, you do it in this way, if you want screw this piece of meat in your way, you don’t belong here, Go to Safeway, you will save few bucks. Last week a Sonoma limo driver “MIKE KELLY” was telling me what sob I was 11 years ago when I refuse to sell him a tri tip whit no spices on it. He, finally cave in. He took one home, he did as I told him, He is one of the best costumer.and, only god knows how many costumers he sent in my way.

  4. Sarah Wilson

    Thanks for the info Jenny! I remember lots of these terms from my animal science courses, but it’s great to see the practical application of the science behind meat! Keep this sort of thing coming- it’s very helpful to this Mama!

  5. Daren Williams

    Thanks for the info, Jenny. I always look in the “manager’s special” bin at the grocery store and buy a lot of aged (brown) steaks at half price! I do occasionally see one that doesn’t look/smell quite. This will help me know when that might be a bad purchase :)

    1. jenniferdewey

      Thanks Daren! My family grew up eating the brown meat because it’s usually what wouldn’t sell! In my opinion sometimes it’s the best because it’s a little more aged! But yes, sometimes there is a fine line. Smell has been my number one indicator of spoiled meat!

  6. Larry Olberding Jr. (@TheDailyCowman)

    Damn you, damn you! Giving away this ranchers secret way of getting inexpensive meat! As a rancher yes we have our own beef but I also buy beef at two local grocery stores fairly regularly. More than once my urban friends are aghast at seeing me buying beef from the store.

    Two reasons I do, if you watch specials and buy cuts that have lost their color you can save HUGE on beef. Beef just as wholesome, nutritious and delicious as that I would raise and at a cost LOWER than what I could produce the individual cut for. I really liked how you explained the science behind this. Hopefully this information will help a family that because of budget restraints might enjoy a great beef meal they otherwise would pass up!

  7. Cassy'o-pia

    You’ve just saved my dinner. Massively helpful for an ignorant cook like me! Thank you for taking the time to explain in such detail. Looking forward to my steak now, without worrying!

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