Spots of mold on the bottom of a pineapple?

What you see: Mold on the bottom of your intact pineapple.
What it is: Fungal growth on dead plant tissue.
Eat or toss: If the rest of the pineapple looks fine, cut into it. As long as you don’t see any signs of decay inside the pineapple, the edible portion of the fruit should be fine. 

Can you eat a pineapple that has mold on the bottom?

Sometimes it seems like every pineapple at the store has some specks of something-or-other on the bottom. I often see black smudges that remind me of mildew, but I’ve also seen red and greenish spots. So, is a pineapple with spots like these still OK to eat?

As long as the inside of the pineapple looks good, some fungal spots on the exterior of its bottom shouldn’t be an issue. Those spots won’t even meet USDA’s designation of “damage” when it comes to grading pineapples.

The fungi that grow on the dried leaves and stems on the bottoms of pineapples typically only eat dead plant parts. So, they’ll chow down on the dried out bits, but won’t try to get past the fruit’s tough outer layer to attack the juicy, inner flesh (in a raw pineapple those cells are actually still alive, respiring and running metabolic processes). Fungi designed to eat dead material aren’t equipped to breach the tough outer layer and take on the inner, living cells. 

All that said, some more aggressive microbial invaders could make it inside the pineapple and cause it to rot, especially if the fruit is injured during harvest and transit. So, when you cut it open, you’ll want to scan for any obvious signs of a problem. That could be browning, breakdown of tissue, sliminess, odors and oozing liquid. The pineapple’s insides might be soft and watery, or you could see brown or black areas. 

“What you worry about is if you were to cut into it and there was some excitement,” said David Miller, a research professor at Carleton University who specializes in fungi and fungal toxins.

You obviously don’t want to eat rotting pineapple. If the decay is only in a limited area, you could cut that off with a wide margin and try your luck with the rest. Also, brown, broken down areas inside the pineapple don’t necessarily represent the work of microbial invaders; storing a pineapple in too-cold conditions can also lead to water-soaked brown areas in its flesh.

Is moldy pineapple safe to eat?

If you’re only seeing mold on the stem and leaves on the bottom of the pineapple, as in the images in this post, and the pineapple looks fine when you cut into it, then it should still be fine.

If, however, you discover mold on pieces of cut pineapple, you should throw them away. Or, ideally, compost them.

If you like pina coladas
And you’re not into mold
If it’s only dead tissue,
Then your pineapple’s gold!