Why 'Watermelon Flavor' Is Nothing Like Real Watermelon

Imagine biting into a cool, crisp slice of watermelon on a hot summer day. Now, pivot and think about the last time you ate something watermelon-flavored — like a Sour Patch Kids watermelon candy or watermelon Jolly Ranchers. It's fair to say that the two are nothing alike. 

We've become accustomed to fruit-flavored foods tasting nothing like their fruity counterparts, from artificial banana essence to cherry-flavored things tasting more like medicine than fruit, but what specifically makes artificial watermelon taste so off-base from its authentic fruity muse? Well, it's simply because we don't yet have the capabilities to synthesize watermelon's complex flavor, which includes compounds like (Z)-3-hexenol, citrulline, and amino acids. Instead, flavor chemists have to build artificial watermelon's flavor out of compounds like ethyl butyrate and artificial sweeteners. So while these watermelon-flavored candies and syrups are pretty tasty, they don't really taste much like the refreshing, watery fruit we've come to associate with summer.

While there has been work done to synthesize watermelon's complex flavor and aroma as much as possible, there are also challenges to getting those compounds to be stable enough to become a food additive. Watermelon aldehyde (seriously, that's its name) is the molecule that scientists have come closest to when trying to mimic watermelon's aroma — but it is not stable enough to be used as an additive.

One of the other big challenges of synthesizing watermelon's flavor is that different types of watermelons have different flavors — meaning there is no such thing as a universal "watermelon" flavor. For example, red watermelons contain lycopene, which is the same compound that makes other red fruits, like tomatoes, red. When lycopene breaks down, it forms citral, which we perceive as lemony. Orange watermelons get their color from beta-carotene, which gives them both a different hue and flavor than red watermelons. It's fun to think that one day, we could have Crimson Sweet-flavored watermelon candies sitting next to Yellow Doll watermelon-flavored syrup. But for now, universal "fake" watermelon will have to do.