Tip Sheet

Masking Fragrances


Masking Fragrances:

 How chemists tame some foul-smelling but incredibly effective ingredients.

What do you do when you uncover a skincare ingredient that has remarkable effect on reducing the size and depth of wrinkles, adds radiance to the complexion but smells like rotten cabbage?  That’s the reality that skincare chemists face every day as they strive to improve anti-aging serums and creams. Sometimes the most effective ingredients are the least pleasant on the senses. (Frequently, the cause of the smell is due to oxidation – when raw materials come in contact with oxygen, skin or bacteria.)

“My team of chemists deal with this issue every day,” explains Burt’s Bees’ Celeste Lutrario.  “Quite often we’ll discover the benefit the ingredient gives to the performance and aesthetics of the formula outweighs the slight odour that it may impart.  So in that case we would choose to use what we call a “masking agent” instead of jeopardizing the product performance.”

When such malodorous smells pop up, many skincare chemists turn to Jack Corley, executive vice president of Trilogy Fragances Inc. in Lakewood, New Jersey. He is considered one of the world leaders in this field.  “It’s important to understand that masking fragrances are designed to cover the malodor – not add a new scent,” he says.  “They are strictly functional. That is, they should be ‘odour neutral’ when added to the base.” He says he is most often asked to mask the odour of the base of a product, especially natural bases with protein and herbal extracts. These can have the most off-putting scents.

So, what’s the secret to developing an effective masking fragrance? “Test, test, test.  You have to test various ingredients to see which ones blend/cover the malodor without adding a new odour.  There’s a great deal of trial and error involved along with a thorough understanding of the chemistry of the base.” He also says it is critical to do significant testing to see how the masking fragrance stands up over time and under different temperatures.  Jack even uses an “incubator” in his lab to stimulate a year’s worth of shelf life.

With this information in mind, it’s important to understand that products labeled fragrance-free aren’t necessarily free of fragrance.  They may contain a very small percentage of masking fragrances to make the use of the product much more enjoyable.  But they won’t contain added scents like floral extracts or vanilla. It’s these type of fragrance that some consumers can be sensitive to.  Rarely does anyone react to masking fragrances.

In the end, masking fragrances are infinitely useful to skincare chemists.  They allow you and I to enjoy the benefits of the most advanced ingredients in a manner that is pleasant to apply and wear.