Ground beef is commonly used to make burgers, meatballs, and sausage, as well as tacos, lasagna, and savory pies.

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.

Spoilage 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.

Check the color
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.

Inspect the texture
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.

Perform a smell test
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.

Check the expiration date
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 is likely to 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, in which case it can last up to 4 months.

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