Watermelon and 2,6-Dimethyl-5-heptenal (FEMA#2389)



Memorial day weekend is the unofficial start of summer and that means watermelon. Watermelon is the fruit we pack in the cooler for picnics at the park.

In contrast, watermelon flavored candies are not a universal American favorite. Some people think only “monsters” like watermelon candy.

When LifeSavers Five Flavors replaced the green lime flavored candy with a green watermelon flavored candy, it was a sad day. Like candy blog mentioned we were not asked what flavor we like; they just changed it.

Personally, I find that watermelon flavor always seems to taste like cleaner or chemicals. Often, this is because a chemical found in watermelon and known to characterize it, 2,6-Dimethyl-5-heptenal (aka melonal) is too high (e.g. 0.1 ppm rather than 0.05 ppm).

The best description for 2,6-Dimethyl-5-heptenal is “powerful”. 2,6-Dimethyl-5-heptenal is also green, fatty, and has sharp notes reminiscent of melons. At very low levels it is a useful component in watermelon flavor or at the wrong level it makes the flavor seem like it’s contaminated with cleaner.

Watermelon flavor is a really difficult flavor to create. Components of watermelon flavor are often used in perfumes for cosmetics and cleaning compounds as well as flavor. Consumers automatically associate the flavor with cosmetics unless the flavor is perfectly blended. There is no room for mistakes, it’s easy to get watermelon flavor wrong.

When creating a watermelon flavor, think about what the consumers enjoy about watermelon. Try to re-create the juicy sweet ever so lightly flavored fruit.

Sweet flavor components are the esters found in many fruits: ethyl butyrate, ethyl acetate, ethyl isobutyrate and the crystals used in most fruit flavors: vanillin and maltol. A light sweet floral note is needed to balance the harshness of the aldehyde: geranyl acetate, octyl butyrate, and methyl heptanoate. The ketone, anisyl acetone, can add the fruity, seedy note found in watermelon. Aldehyes, like octanal and 2,5-dimethyl-5-heptenal add that subtle sharp rind note, but be careful. Be careful that the flavor ages well and stays balanced and be careful that care is used with formulating and measuring.

I once had a flavor trainee assigned to assist me with formulating. She would never follow my instructions to make dilutions when making small batches of flavor. Her laziness was annoying. Because of the limitations of scales, there are no shortcuts.  2,6 Dimethyl-5-heptenal illustrates the importance of the accuracy of the scales used in both formulating and production. The difference between 0.05ppm and 0.1 ppm can be relevant to taste.






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  1. Alejandra says:

    Hi Susie, I stumbled upon your blog, and want to ask you a question about quemestry and food. Ok so you might find this story a little strange and I hope im not taking to much of your time. Im a cook in Madrid, and I want to get a culinary tattoo, its going to have several elements of my life, like a collage, and I want to include my culinary career, but I dont want it to be obvious. And now you are going to think im dumb… but i was looking for the chemical structure of butter (yai french cusine!) and well now I realize its not that simple. I found a chemical sign for ´Polyphenolic (flavone) structure from which flavonoids are derived.` and it says something about wine and flavor, which I didnt really understand. do you think you could help me find a quemical symbol or structure that really represents flavor, that could represent the culinary aspect of my life? Ill be very thankful for any imput or ideas you could give me. Thanks a lot! And congratulations on your blog, I found it very interesting!

    • Susie Bautista says:

      Hi Alejandra: Interesting request. My creativity is challenged on this one. Personally, when I was designing my blog, I wanted the logo to be a pie with aroma whiffs coming out as birds (my favorite animal), but my husband told me that was ridiculous. In fact he gave me “that” look (like I’d lost my mind). I STILL love my pie idea, but for your interest, perhaps the aroma coming off should be chemical structures? Pie has butter, fruit, sweet notes. You can choose a variety of favorites and not focus on one (who could choose just one?). Anyway, I’m probably not much help, but I’ll keep your question posted. Maybe others have brilliant ideas they would like to share? Susie

  2. Sophia Zhao says:

    Hi,Susie.Your blog is very interesting and full of useful information,and I am glad to find it.Maybe my english is not as good as native speakers,but I want to communicate with you .

    I am a junior flavorist in China,work in a japanese company. I really wonder how a flavorist can ensure the top note,the middle note,and the last note,how to make sure the best rate bettween the? how long will it make to a perfet flavor?

    • Susie Bautista says:

      Hi Sophia: My experience was that I learned to balance a flavor (top-middle-bottom) by copying other’s flavors. Sometimes, it can take 50-100 trials to copy a flavor. It may take weeks. It takes time to develop skills as a flavor chemist, so be patient and work hard. My career began at a Japanese company, T. Hasegawa. I had excellent mentors. Best of luck, Susie