When you’re hanging out with friends (or even better, a GF/BF), do you ever worry about bad breath? If so, you’re likely to carry around some kind of “protection”… mouth spray, mints etc.
One well-known product is Clorets - a chewing gum that’s suppose to act as a breath deodorizer. If you’ve looked at the ingredient list, you might have noticed that Clorets contain “water soluble chlorophyll”.
Most people have heard of chlorophyll – that key molecule important in photosynthesis. But as a human, you certainly don’t rely on photosynthesis. So why the heck is it in your gum!?
What is Chlorophyll?
A chlorophyll molecule looks a bit like a tennis racquet. It has a “head” (porphyrin ring) and a “shaft” (phytol) which are made up of many carbon-hydrogen bonds. And just like a tennis racquet, it has a “sweet spot” – the center of the ring where a single magnesium ion is located and held in place with nitrogen atoms.
Chlorophyll is considered photoreceptive since it absorbs light in the blue and red spectrum (wavelengths 400-700 nm) and reflects unabsorbed light in the green spectrum. This is what gives plants their distinctive green colour.
Did you know? The term “chlorophyll” is derived from the Greek words khloros (pale green) and phyllon (a leaf).
Because of its unique ability to capture light, chlorophyll is a key component in photosynthesis. This is a chemical reaction involving carbon dioxide and water where plants use the energy in sunlight to produce sugars (carbohydrates) for growth.
Let’s now look at how chlorophyll started being used in consumer products.
Commercialization of Chlorophyll
Have you ever heard of the word putrefaction? It’s just a fancy term for “rotting” where plant and animal proteins are broken down by bacteria in the absence of oxygen. If you’ve ever left a banana or some other fruit out to rot, you know that after a while it starts to stink.
The same thing happens when a wound becomes badly infected; a foul odour is produced. As it turns out, scientists studying the properties of chlorophyll during the first half of the 20th century made an important discovery – chlorophyll could reduce the odour associated with infections.
So by the early 1950s, there was a lot of interest in promoting “odour-eating” products that contained chlorophyll. These included mouthwashes, cough drops, cigarettes, dog food – even toilet paper!
Did you know? The strength of an odour-causing compound is proportional to the logarithm of its concentration (Weber-Fecher law). So if 99% of the compound is eliminated, our nose perceives the smell to be reduced by only 66%.
Once the 60’s rolled around, however, most of these products disappeared from store shelves. It seems consumers weren’t buying into the chlorophyll “miracle”. After all, cows eat a lot of chlorophyll, but they still stink don’t they?
One product that did survive, however, was Clorets.
Clorets and Chlorophyll
Clorets were first introduced in 1951 by Adams Sons and Company. As with other companies, they faced a challenge with using chlorophyll in their chewing gum. Specifically, chlorophyll in its natural form is difficult to extract, breaks down easily and is water-insoluble.
Did you know? Plants that are rich sources of chlorophyll include algae, spinach and parsley.
To solve this problem, Adams used a synthetic chemical developed by scientists known as chlorophyllin. Its structure is quite similar to chlorophyll, except it’s missing the “shaft” (phytol unit) and a copper ion replaces the magnesium in the “sweet spot”. Unlike chlorophyll, chlorophyllin is quite stable and is water-soluble.
So when Clorets is advertised as containing “water soluble chlorophyll”, we now know they actually mean chlorophyllin. And according to at least one scientific study I’m aware of, it really does work as an effective breath deodorizer.
Chlorophyll was once described as “green gold” because of its potential commercial value. Today, scientists are interested in chlorophyllin as a possible treatment for burns and cancer.