Purple Meat, Steak & Beef – Why Beef Changes Color
Updated: 1h
Why beef changes color comes down to one thing: oxygen. With no oxygen, beef is purple. With plenty, it is bright red. Somewhere in between, it turns brown.
If you have shopped Pre® 100% Grass-Fed & Finished beef, you have probably noticed the purple color. Julie, our Pre Quality Manager, walks you through what is going on, what each color means, and why we vacuum-seal our beef.
Do you ever wonder why our beef is purple in the package?
It is not often that you see purple meat, like a purple New York strip or ribeye at the grocery store. Most of the steaks and ground beef you come across are red, and we tend to think red looks more appealing. But if you have shopped Pre® beef, you are probably familiar with the purple.
Keeping meat fresh is something we work hard at and constantly monitor at Pre Brands. One of the more natural ways to combat spoilage is vacuum-sealing our products, which removes the oxygen. That returns the beef to its natural state and in turn keeps it fresher, longer.
We made a quick video on Instagram that touches on this. Watch it here.
The color of fresh beef is determined by myoglobin, a protein found in muscle tissue that is naturally purple. It changes color depending on how much oxygen it is exposed to. When exposed, the iron in the muscle reacts and becomes unstable, turning either red or brown depending on the level of oxygen present. That is why beef changes color.
Julie explains why beef changes color
We asked Julie, our Pre® Quality Manager, to talk us through it in more detail. Watch her discuss the different meat colors in our video:
There are 3 main states for this color change
State 1, oxymyoglobin: atmospheric oxygen (O2) is present, and the beef is bright red.
State 2, metmyoglobin: oxygen (O2) partial pressure is low, and the beef is brown.
State 3, deoxymyoglobin: no oxygen (O2) is present, and the beef is purple.
So why does most packaged beef look red?
Vacuum-packaged beef looks distinctly different from beef in an overwrap tray or a MAP (Modified Atmosphere Packaging) package. It appears deep red or purple, compared with the bright red you usually see in other packages and behind the butcher counter. The reason is oxygen.
Vacuum package: there is no oxygen in the package, which makes it an anaerobic environment. The meat turns deep red or purple. This is deoxymyoglobin.
Overwrap tray: the package is open to the air we breathe, so oxygen is present and the beef is bright red.
MAP package: gasses such as oxygen, carbon dioxide, and nitrogen are added to keep the bright red color. This is oxymyoglobin.
When you open a Pre® vacuum-sealed package, the beef changes to a bright red. We call that blooming. Preserving freshness means removing all of the oxygen from the package, and when you open it, the beef meets oxygen and turns red. Because we seal our meat airtight, you get to see that transformation.
You may notice a similar effect behind the butcher counter or in trays. When steaks overlap, the covered steak can turn brown because it gets less oxygen. That is metmyoglobin, the brown state.
The presence of oxygen gradually deteriorates meat and oxidizes fat. In MAP packaging, additional gasses are added to prolong freshness. With Pre®, we do not add any gasses to help extend freshness. We just remove as much air as possible.
The Pre® difference
The bright red color of beef is unstable, and oxygen gradually deteriorates the meat and oxidizes the fat. That is why beef does not last as long behind the counter or in overwrap trays. MAP packaging fights this by adding gasses like nitrogen and carbon dioxide, but eventually the oxygen starts to spoil the meat. With Pre packaging, we do not add gasses to extend the life of the beef. We just remove as much air as possible. Without oxygen, the beef returns to a stable color and stays fresher, longer.
We tested our steak packaging in a five-day fridge test alongside a steak wrapped in butcher paper. See the results of our five-day fridge test.
Learn more about our sourcing and expiration dates. And if you do not see Pre in your local grocery store, download this form and give it to the meat manager so we can be near you soon.
FAQ
Why is Pre beef purple in the package?
Pre beef is vacuum-sealed, which removes the oxygen. Without oxygen, beef shows its natural purple color.
Is purple beef safe to eat?
Yes. Purple is the normal color of vacuum-sealed beef. Always check the use-by date, and trust your nose: a sour smell or slimy texture means toss it.
Why does beef turn bright red when I open the package?
That is called blooming. Once the package is open, the beef meets oxygen and turns bright red.
Does brown beef mean it has gone bad?
Not always. Brown can mean the beef had less oxygen exposure, like a steak that was overlapped in a tray. Check the smell, the texture, and the use-by date before you decide.
More on what the pack tells you: read the importance of Pre beef packaging.
Where can I buy Pre 100% Grass-Fed & Finished Beef?
Whatever the color, Pre Brands beef is a lean, High Protein way to put healthy, delicious dinners on the table. Use our store finder to find a store near you, browse all Pre products, or find us on Instacart. New to us? Start with Grass-Fed Beef 101.
