Ground beef may be your kitchen burger staple, but how do you tell your ground beef has gone bad? Changes to color, texture, and smell, along with the expiration date can offer clues.

Ground beef is commonly used to make burgers, meatballs, and sausage, as well as tacos, lasagna, and savory pies. It accounts for about 62% of all beef sold in the United States.

However, since grinding the meat exposes more of its surface to air, spoilage organisms have more space to attach to it. Thus, it goes bad faster than steak or other larger cuts.

Spoilage and pathogenic bacteria may both affect ground beef. These bacteria are generally not harmful but cause food to lose quality and develop a bad odor and taste.

On the other hand, pathogenic bacteria are dangerous, as they can lead to food poisoning. Furthermore, spoilage makes it more likely for them to be present in your food. Therefore, even though spoilage bacteria won’t make you sick, you should always discard spoiled ground beef to avoid consuming disease-causing microorganisms.

Here are 4 ways to tell whether your ground beef has gone bad.

Ground beef may change color due to multiple factors, including temperature, light, microbial growth, and exposure to oxygen.

Fresh, raw ground beef should be red due to its levels of oxymyoglobin — a pigment formed when a protein called myoglobin reacts with oxygen.

The interior of raw ground meat may be greyish brown due to a lack of exposure to oxygen. This doesn’t indicate spoilage.

Nevertheless, you should throw away ground beef if it has turned either brown or gray on the outside, as this indicates that it’s beginning to rot.

Additionally, mold can spoil cooked ground beef, so you should toss your leftovers if you notice any fuzzy blue, grey, or green spots.

Another way to check your ground beef is by conducting a touch test. Fresh ground beef should have a relatively firm consistency that breaks apart when you squeeze it.

However, a sticky or slimy texture — either when cooked or raw — may indicate the presence of spoilage bacteria. You should toss it immediately.

To avoid spreading bacteria from one surface to another, wash your hands thoroughly after touching raw meat.

This test is probably the easiest and fastest way to determine whether meat has spoiled. It applies to both raw and cooked ground beef.

Though the scent of fresh ground beef is barely perceptible, rancid meat has a tangy, putrid odor. Once it goes bad, it’s no longer safe to eat.

The scent changes due to the increased growth of spoilage bacteria, such as Lactobacillus spp. and Pseudomonas spp., which may also affect the flavor.

If you don’t notice a funny scent but still see signs of spoilage in color or texture, it’s still safest to throw it away, as pathogenic bacteria cannot be smelled.

Sell-by and expiration dates are additional guidelines for determining whether your ground beef is good.

A sell-by date tells the retailer how long a product can be displayed for sale. Ground beef can be refrigerated and safely eaten up to 2 days past this date.

Meanwhile, the expiration date — also labeled as “best before” — tells you when the product will likely start going bad. Food will have the best taste and quality before this date.

You shouldn’t eat ground beef past its expiration date unless it’s been frozen, which can last up to 4 months.

Be sure to carefully read the product label when buying ground beef.

Spoiled ground beef is dangerous to eat because it may contain pathogenic bacteria, which are responsible for foodborne illnesses. Symptoms include fever, vomiting, stomach cramps, and diarrhea — which may be bloody.

Disease-causing microorganisms grow rapidly in food that’s been left at room temperature and are more likely to occur in spoiled food.

The most common harmful bacteria in ground beef are Salmonella and Shiga toxin-producing E. coli (STEC). Outbreaks of infections related to these bacteria occur fairly frequently in the United States. It may take several days for symptoms to appear.

To destroy these bacteria and reduce your risk of food poisoning, cook ground beef thoroughly and use a meat thermometer to verify that its internal temperature reaches 160°F (71°C).

It’s safest to never eat raw or spoiled ground beef.

Proper handling and storing are key to avoiding food poisoning from ground beef. Here are a few safety tips:

  • To minimize the time that ground beef is left unrefrigerated, buy it last and head home directly from the store.
  • Choose a cold package to the touch and in good condition, without holes or scratches.
  • Check the color and expiration date of the meat.
  • Keep raw meat separately in your cart to avoid cross-contamination or the spread of bacteria to other food items.
  • Refrigerate or freeze it when you get home or within 2 hours of purchase. Make sure the fridge temperature is below 40°F (4°C).
  • Keep it in a bag on the lowest shelf to prevent its juices from leaking.
  • Thaw frozen beef in the fridge to keep it cold while defrosting. Never leave at room temperature for more than 2 hours.
  • Refrigerate your leftovers within 2 hours of cooking and eat them within 3–4 days.

Remember to wash your hands thoroughly after handling ground beef, and don’t forget to your clean kitchen counters and utensils.

Below are frequently asked questions regarding ground beef.

What will bad ground beef smell like?

Spoiled ground beef will have a pungent, putrid smell. Ground beef that is safe to eat typically has little to no perceptible smell.

Can ground beef smell a little but not expired?

All ground beef has a slight aroma of iron. Ground beef nearing its expiration date may have a slightly more noticeable smell but is still safe to eat. However, if a product has a noticeable, pungent smell, it is most likely spoiled and should be discarded.

Is it OK to cook grey ground beef?

When inspecting a package of ground beef, it is common for the outside to appear red or pink, while the inside may appear grey or brown. This is due to a lack of oxygen in the center of the beef.

However, if ground beef is grey on the outside, it is unsafe to cook and consume and should be disposed of.

Ground beef is very popular but highly perishable.

A few simple techniques, including looking for changes in color, odor, and texture, can determine whether your ground beef has gone bad.

Though the bacteria that cause meat to spoil aren’t generally harmful, other disease-causing microorganisms may proliferate when it goes bad. To reduce your risk of illness, you should always cook meat thoroughly and avoid eating spoiled or undercooked ground beef.