Is beef safe to eat if it turns brown?

When raw beef is freshly cut, it has a bright red color. However, after exposure to air for some time, the surface of the beef will start to turn brown. This browning does not necessarily mean the beef is spoiled or unsafe to eat. Here are some quick answers about the safety of brown beef:

Why does raw beef turn brown?

The brown color is caused by a natural chemical reaction involving myoglobin in the muscle fibers of the beef. Myoglobin is a protein that stores oxygen in muscle cells. When oxygen interacts with the iron in myoglobin, it gives the beef a red color.

When oxygen is removed, such as when raw beef is vacuum-packed, the myoglobin turns dark purple or maroon. Once exposed to air, the myoglobin reacts with oxygen again and forms a pigment called oxymyoglobin, which gives beef its red color.

Over time, the oxymyoglobin oxidizes further and forms another pigment called metmyoglobin. Metmyoglobin has a chemical structure that reflects light differently, making the beef appear brown.

Is brown beef spoiled and unsafe to eat?

Not necessarily. If beef has been stored properly at refrigerator temperatures, discoloration alone does not indicate spoilage. Fresh beef can turn brown within a few days, but as long as it remains cold at 40°F or below, it should still be safe to cook and eat.

The main factors that cause spoilage and make beef unsafe are bacterial growth and breakdown of tissues. Refrigeration helps prevent this. So while brown beef may not look as appealing, it can still be perfectly fine quality and edible.

How to tell if brown beef is spoiled?

Here are some ways to determine if browned beef has spoiled and may not be safe to eat:

  • Unpleasant odor – Fresh beef has a slight bloody/meaty smell. Spoiled beef smells sour or off.
  • Slimy texture – Slime on the surface indicates bacterial growth.
  • Mold growth – This appears as fuzzy patches and should not be consumed.
  • Discoloration deep beneath the surface – If the inside of the beef also turned brown, it is a sign of microbial spoilage.

So it is important to consider all the sensory clues together. Change in surface color alone does not mean spoiled beef, but if combined with an off smell, texture changes or mold, it should be discarded.

What causes beef to turn brown prematurely?

There are a few reasons why beef may turn brown before its expiry date or without other signs of spoilage:

  • Exposure to light – UV light accelerates the oxidation of oxymyoglobin into metmyoglobin, causing premature browning.
  • Improper storage – If beef is kept above 40°F, bacteria can grow faster and cause surface discoloration.
  • Processing and handling – Rough mechanical tenderizing, grinding, or excessive cutting can denature the meat proteins and speed up browning.
  • Moisture loss – Freezing and thawing or drying the surface can remove moisture and affect myoglobin.

While these factors may lead to early browning, the beef may still be safe if stored at proper refrigerator temperatures.

Can you reverse the browning of beef?

Unfortunately, once the myoglobin has oxidized into metmyoglobin, the browning of beef is irreversible. However, you can slow down or minimize premature browning by:

  • Promptly storing beef in the fridge below 40°F or in the freezer at 0°F.
  • Keeping beef away from light by wrapping tightly in opaque packaging or using a refrigerator cover.
  • Avoiding unnecessary handling and cutting of meat to limit oxidation.
  • Maintaining sealed packaging integrity; rewrap if opened.

While you can’t reverse the browning, properly handled brown beef is still perfectly safe to cook and eat.

Is browned ground beef safe to eat when cooked?

Yes, thoroughly cooked browned ground beef is safe to eat if it was stored properly. Any bacteria present would be destroyed by cooking to the recommended internal temperature.

Ground beef browns faster than whole cuts of beef because grinding exposes more surface area to air. The USDA recommends using or freezing ground beef within 1-2 days of purchase for best quality.

Check that refrigerated ground beef remains cold at 40°F and shows no signs of spoilage like odor, slime or mold. Cook ground beef patties and crumbles to an internal temperature of 160°F, measured with a food thermometer, to eliminate any foodborne pathogens that may be present.

The browning does not significantly affect the flavor or texture of ground beef. Fully cooked patties and meatballs made from browned ground beef are safe to eat.

Can you cook and eat brown steak and roasts?

Yes, brown whole cuts of beef like steak and roasts are perfectly safe to cook and eat. The browning is only superficial and does not penetrate below the surface.

Check for any off odors and slime before cooking. As long as the interior of the beef still looks red and fresh, the beef has not spoiled. Cook steaks to a minimum internal temperature of 145°F and roasts to 160°F.

Searing and browning the exterior of steaks to your desired doneness will also kill any bacteria present on the surface. Enjoy your browned steaks and roasts without any worries about safety or quality.

Does cooking kill any bacteria on brown beef?

Yes, proper cooking destroys any bacteria that may be present on brown beef. Pathogens like Salmonella, E. coli and Listeria can survive on the surface of fresh beef. Cooking beef to the recommended safe internal temperatures kills these harmful bacteria.

Here are the minimum safe cooking temperatures for different cuts of beef:

Beef cut Minimum internal temperature
Steaks, roasts, chops 145°F (medium rare)
160°F (medium)
Ground beef 160°F

Use a clean food thermometer to check internal temperatures when cooking. This ensures any bacteria that may be present are destroyed, regardless of the freshness or surface browning of the beef.

Can you freeze brown beef to stop spoilage?

Freezing is an excellent way to extend the shelf life of fresh beef, even if it has started to brown. At 0°F or below, bacterial growth stops, preventing spoilage.

To freeze beef:

  • Package beef in air-tight wrapping to prevent freezer burn.
  • Freeze as soon as possible before further browning occurs.
  • Label packages with date and contents.
  • Maintain freezer at 0°F or below.
  • Use frozen brown beef within 4-12 months for optimal quality.

Brown beef often retains good quality when frozen properly. It is safe to thaw and cook frozen brown beef that shows no signs of freezer burn or other damage.


The browning of raw beef is a natural process that does not inherently make the beef unsafe or low quality. Proper refrigerated storage is key for maintaining freshness and safety.

Discard beef that has turned brown if it also has an off smell, slimy texture or mold growth. Otherwise, brown beef is perfectly fine to cook as long as it reaches the recommended safe internal temperatures.

Freezing can stop browning and spoilage of beef. With proper handling, preparation and cooking, browned beef poses no additional health risks compared to raw red beef.

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