When it comes to avocados, a little bit of browning isn't necessarily a bad thing. In fact, some varieties — like Hass avocados — will turn darker on the outside as they ripen (via My Foodbook). Look for deep green, nearly purplish skin to determine if your fruit is ready. Still feeling stuck at the grocery store? The superfood's softness is also an indicator of ripeness and, in some cases, spoilage. Press gently on the skin, and if you feel a little bit of give, the fruit is guacamole-ready. However, if pressing on the flesh results in a deep indentation, it's likely bad, as Healthline reported.
Once you cut open the avocado, look for discoloration. According to University of Querétaro professor Elhadi M. Yahia, a few brown spots aren't as bad as people might think they are. "I have absolutely no problem eating them," she told Eat or Toss. These spots might not taste as fresh and creamy as greener sections, but you can always scoop them out. Though beware: if the entirety of the avocado's flesh appears brown or you start to notice streaks of black, throw it out. Eating rotten fruit can lead to symptoms of food poisoning like vomiting, diarrhea, and stomach pain, per Healthline.
Another indicator of spoilage is texture. Though "stringy" flesh is often produced by newly-planted trees, according to California Avocados, it can also mean that your fruit has expired.