Anyone who has every plowed their way through a pile of fresh pineapple has most likely felt its sting. Eating too much of the fruit can make your mouth feel scraped raw, which is quite the betrayal when you consider that fruit is supposed to be “good for you.”
The culprit, it turns out, is a little enzyme known as “bromelain,” and it loves to break down amino acids and proteins. This makes the extracted enzyme a very good meat tenderizer, and your mouth—I am sorry to say—is made of meat. (Bromelain is also sold as a “health supplement” online and in various health food stores, but it only has one approved clinical application—removing dead tissue in severe burns).
Why does bromelain hurt?
Bromelain eats through the mucous coating on the inside of your mouth, then gets to work on the exposed proteins. It’s kind of horrific, but doesn’t cause any permanent damage as your mouth can bounce back pretty quickly, provided you don’t continue to eat fresh pineapple after fresh pineapple without pause. The enzyme affects some people a more harshly than others, so it’s entirely possible that you’ve never run into this particular sensation (and it’s entirely possible that I am jealous).
How can you stop pineapples from hurting your mouth?
For those familiar with the feeling, what’s to be done? Some anecdotal information (including an episode of “Ugly Delicious”) seems to indicate that a quick soak in salt water can dampen the enzyme’s affects. This article from Science Meets Food claims that the dissolved sodium chloride disrupts the enzyme’s polarity, which will “destabilize the protein and denature its structure.” Michael Tunick, Ph.D., an assistant clinical professor of culinary arts and food science at Drexel University in Philadelphia told Food & Wine that salt “triggers bromelain to begin working, so by the time the pineapple reaches your mouth, the enzyme has been inactivated,” and that “dipping fresh pineapple briefly in a saltwater solution is the best way to maximize contact between salt and bromelain.”
But there hasn’t been a lot of research into exactly how much salt would be needed to affect the bromelain. Not all pineapples contain the same amount of water, sugar, or bromelain, but soaking the fruit in a saline solution certainly doesn’t seem to hurt. I soaked about half of a pineapple in a solution of two cups of tap water and one teaspoon of table salt for about a minute before eating it and, though I felt some mild tingling at the corners of my mouth and on my tongue, it was not a painful experience. I then ate some of the pineapple that had not been soaked in the salt water, and the tingling got a little more aggressive, but that could have been the cumulative effects of eating a whole lot of pineapple.
There are, however, a couple of other things you can do affect the amount of bromelain that makes its way into your mouth. For starters, always make sure you remove the core, which has the highest highest concentration of the enzyme. Heat will also deactivate the enzyme, so roasting, grilling, and baking are all good strategies (and grilled pineapple is really, really good). Finally, pairing the fruit with tongue-coating dairy can help. Yogurt, crème fraîche, and other similar products not only feel soothing on the palate, they give the enzyme another protein to go to work on, hopefully distracting it from your tongue. (And if all else fails, you can always eat canned pineapple; bromelain doesn’t stand a chance agains the canning process.)