Metaperspirant (INCI: Not Provided) is a simple water, glycerin and starch-based hydrogel that acts in several ways to prevent malodor. William Zicker, of Oobleq, presented the patented technology during the latest SCC Naturally Kiawah Symposium. As Zicker explained, the hydrogel prevents malodor formation via three main mechanisms: it interrupts the precursors; isolates the bacteria; and disrupts and distracts the bacteria.
To interrupt the precursors, chemical similarities among the gel and the components of sebum result in the materials combining, making them unappetizing or unrecognizable to microbes. To isolate the bacteria, since the gel is also chemically similar to the bacterial cell walls, it forms a film to prevent bacteria from accessing the compounds present in apocrine sweat. These compounds would otherwise be cleaved by the bacteria, converting them into malodorous compounds. According to Zicker, in both cases, cohesion appears to be the main mechanism.
In terms of disrupting and distracting bacteria, the glycerin in the gel plays a key role. Glycerin reportedly has antibacterial properties, primarily as an osmolyte. By creating osmotic pressure, it can disable or destroy bacteria cells. Furthermore, glycerin and starch are both carbohydrates that can act as probiotics. Feeding the microbes is said to potentially distract them from interacting with apocrine sweat, preventing malodorous compounds from being generated.
Per Zicker, he worked for ten years on stabilizing the blend. He initially focused on stabilizing a starch suspension in water, and while water alone would not hold starch in suspension, gelatinized starch provided a stable medium to achieve this. Samples open to an ambient environment have remained stable for five years.
See archived: Controlling Odor and Wetness in a Newer, Greener Age
In terms of preservation, the gel has low water activity since the water is contained securely within the gelatinized starch portion gel, rendering it unavailable to microbes. Versions the gel incorporating oils and waxes have been developed and functional ingredients including powders and oils may be added to it.
Metaperspirant is made from familiar food ingredients, omitting undesirable aluminum and appealing to the clean beauty consumer. It acts as a moisturizer for skin and allows the natural process of sweating to occur. Finally, since the gel only requires starch and water, it can be produced from any starch of any plant source, modified or native. This facilitates sustainable and reliable supply chains, including opportunities for locally sourced ingredients.