I’ve come up with a lot of weird theories in my life. When I was younger I thought locking the door helped keep the weather out. I’m still not entirely convinced it doesn’t at least help. In high school we used to wear our pajamas inside out and put toothbrushes under our pillow to summon a snow day. But one of the central theories of my adult life was something I constructed to answer the question: Why do my apples taste like onions sometimes?
I decided that it was because I kept all my produce in one crisper together, apples and onions shamelessly co-mingling with clementines and bell peppers. The apples were leeching the flavor out of the nearby vegetables, I concluded, not bothering to employ the scientific method. Since then, I’ve kept my apples quarantined from my onions, and largely forgot about my apple flavor absorption theory. Until the other day…
more evidence for my “apples absorb flavors of nearby foods” theory: just 1/4 of my apple tastes like jalapeño— it was nearby in the fridge— Julie Beck (@julieebeck) February 27, 2014
There were only one or two jalapeño-flavored bites, which must be because the wily pepper only poked a corner of my Pink Lady. My friend Lindsey responded, bringing me back to the original problem:
@julieebeck Sometimes my apples taste like onions.— Lindsey Kratochwill (@LindseyKrat) February 27, 2014
I’m finally on to something, I thought. Maybe this was my chance to stamp “Case Closed” on just one of my life’s recurring mysteries. I took to the Internet, and saw some promising links. Then I called up Kathleen Brown, a professor of plant science at Penn State, who explained to me that this is indeed a thing, and told me how it works.
Any food can actually absorb the flavor of any other food, she told me, but because of apples’ mild flavor, it’s easier to notice.
“An apple is so fleshy that there’s a lot of air space in it to store those flavors in a way that they can be released later when you’re eating the apple,” she says. “One of the reasons the flesh looks white is because there’s air spaces in between the cells.”
Pears, which are similarly delicate and mild-flavored, often do the same thing, as do potatoes. But since most of us don’t just bite into a raw potato the way we would an apple or pear, that issue doesn’t come up so much.
With regard to Lindsey’s and my specific issue, onions have particularly volatile aroma compounds, Brown says, and, what’s more, they’re sulfurous, “so you would be more likely to perceive them as objectionable.” Their strong flavor, combined with apples’ mild one, makes onion-flavored apples a likely occurrence if you keep them in the same crisper. A box of baking soda can help keep flavors where they should be, but Brown also points out that you don’t need to keep onions in the fridge. So that’s partially my bad. But the important thing is, I was RIGHT.