There is a lot of information out there about how to get a rock-hard pineapple ready to eat quickly. Just try googling it. There are claims that storing it upside down, putting it in a plastic bag, or even just leaving it out on the counter will all lead to ripe, read-to-eat pineapple.
Sorry folks, I have some bad news. Pineapple does not continue to ripen once it’s been picked. Let’s get into it.
Why You Can’t Ripen a Pineapple
When it comes to ripening, fruits fall into one of two categories, “climacteric” and “non-climacteric.” Pineapples are a “non-climacteric” fruit. These monikers refer to a fruit’s production of ethylene gas, which is what causes fruit to ripen once it’s matured. Climacteric fruits — like apples, bananas, and peaches — react to the presence of ethylene by producing more ethylene, which causes them to become softer and sweeter very rapidly. That’s why you can ripen a banana by putting it in a paper bag with an apple. Both fruits produce (and react to) ethylene gas.
Fruits like these can be harvested when mature, but still unripe, as they ripen through their own ethylene production. Climacteric fruits also tend to store their sugars as starch, which is then converted back into sugars as the fruit ripens. They get both softer and sweeter after they’ve been picked.
Non-climacteric fruits — like pineapples, cherries, and grapes — don’t ripen in the same way. They don’t create their own ethylene and therefore need to be connected to their parent plant to continue to ripen. Per Harold McGee in On Food and Cooking, “Non-climacteric fruits … ripen gradually, usually don’t store sugars as starch, and so depend on their connection to the parent plant for continued sweetening. Once harvested, they get no sweeter, though other enzyme actions may continue to soften cell walls and generate aroma molecules.”
This means that while leaving a pineapple on your kitchen counter for a few days may soften it up, develop a more powerful smell, and even change color, it’s not becoming any closer to ripe. Per Mary Lu Arpaia of the UC Davis Department of Plant Sciences, “Pineapple … will respond to low-dose ethylene treatment, which triggers the degradation of chlorophyll (green color) in the citrus peel. Ethylene also can cause the degradation of chlorophyll in the rind of the pineapple, but this is not tied to internal ripening effects.” Pineapples need to be picked when they’re ripe in order to be ripe when they get to you.
How to Sweeten Fresh Pineapple
The good news is that even though there’s no way to ripen a pineapple that was picked before its prime, you can lightly sweeten unripe pineapple through cooking. Cooking intensifies the sweetness of fruit. The trick is to cook it very lightly, so the pineapple becomes a bit sweeter, but not fully cooked through. A quick trip to a low oven is enough to bring out the sweetness in an unripe pineapple.
Of course, incorporating less-than-perfect produce into cooking and baked goods is a tried-and-true method for using up fruit you’d rather not consume raw, whether it’s due to it being under or overripe. If you’re not looking to eat your pineapple raw, a less-than-ripe pineapple could find a perfect home in a classic hummingbird cake, a cocktail, a grilled skewer, or even a bruleed dessert.
