There is a strong association between the amount of visible suds (foam) and the power of a cleaning product, although the foaming agents that cause lather and suds have received intense scrutiny in recent years. Let’s take a closer look at the role of foaming agents in everyday cleaning products.
A Brief History of Soap Suds
The small bubbles that form when we use soap are a by-product of the micellar structure of surfactants. Each soap molecule has a hydrophobic end and a hydrophilic end. When exposed to water, the hydrophobic ends rise to the surface, trying to avoid the water. As they move, the hydrophilic ends stick to water and pull it along. The molecules naturally form a sphere called a micelle, trapping a thin layer of water that surrounds a bit of air. As the micelles are formed, they decrease the surface tension of the water, allowing the water-borne cleaning agent to penetrate more deeply, and trapping soil inside the micelle, making it easier to rinse away.
Historically, commercial soaps and cleaning agents were extremely strong. The amount of lather or suds generated by the cleaning products was important for consumers, because suds perform several important functions:
- Suds indicate the presence of a cleaning agent, rendering products visible in water
- Suds demonstrate the strength and effectiveness of the cleaning agent, as lather diminishes over time
- Suds “cling” to surfaces, prolonging the working time of the cleaning agent
These early soaps and detergents were also so strong that they dried and damaged the skin, destroying the delicate oils that keep it healthy and moisturized.
Over time, companies developed detergents and surfactants that were just as effective at cleaning but gentler on the skin. These products created less lather during the cleaning process, but companies quickly discovered that consumers still strongly believed that suds were indicative of cleaning power and effectiveness. Companies began adding foaming agents to cleaning products to satisfy this consumer expectation.
In recent years, there has been a backlash against many of these foaming agents, as consumers are perceiving them as chemical additives that do not increase effectiveness. Today, many consumers will accept suds-free cleaning and hygiene products when they are perceived as more natural.
Most Common Foaming Agents
Despite the desire for more natural cleaning and hygiene products, and the reluctance to use certain unwanted chemicals, most consumers still want the perception of effectiveness that lather provides during the cleaning process. Some of the most common foaming ingredients are:
- Sodium laureth sulfate. SLES is an inexpensive surfactant typically derived from palm kernel or coconut oil. It is used in a huge range of products, from shampoos and toothpaste to household cleansers and herbicides. It is a safe, gentle, effective ingredient. SLES production creates the byproduct 1,4-dioxane, classified as possibly carcinogenic, which may in turn contaminate SLES during manufacture. While SLES is recognized as safe and effective, some consumers seek to avoid it.
- Sodium lauryl sulfate. SLS is produced in virtually the same way as SLES, without the step of ethoxylation. It is another effective surfactant and foaming agent, found in cleaning and hygiene products. SLS is also often used as a food additive, improving emulsifications and stability in whipped or foamed ingredients. In cosmetics, it is used to make products thicker and smoother, for a more stable, uniform application. SLS may cause skin irritation in some people, and toothpastes with SLS may be associated with dry mouth.
- Ammonium lauryl sulfate. Like SLS, ALS is produced like SLES, without ethoxylation. It is a high-foam surfactant with low incidence of irritation or toxicity, and is thus often found in products exposed to the skin, like shampoos, facial cleansers, and body washes. Even in very high concentrations, ALS is non-irritating, although it is recommended for applications where it is used and rinsed away (like a cleanser or wash), rather than being worn on the skin (like a lotion or cosmetic).
- Cocamide DEA. Cocamide DEA is an inexpensive foaming agent derived from coconut oil. Unlike the sulfates, it is not an effective surfactant and does not have strong cleaning properties, but is a foaming and emulsifying agent used in shampoos and soaps. Like SLES, it is classified as “possibly carcinogenic to humans,” and it has a high potential for skin irritation.
- Cocamidopropyl betaine. CAPB is a detergent and surfactant derived from coconut or palm kernel oil. Like Cocamide DEA, it is used more to create foam and suds than for any inherent cleaning capability, and is often found in soaps and bath products. Despite being considered a potential allergen, most studies show that these reactions are probably due to irritation rather than allergies, and that they are more likely attributable to common CAPB production contaminants, rather than CAPB itself.
It is important to note that despite their poor reputation, sulfates are also highly biodegradable and do not persist in the environment, unlike some other detergents and surfactants.
Should We Skip the Suds?
More and more consumers are becoming accustomed to cleaning and hygiene products that do not foam or create suds, like micellar water for facial cleansing, or many natural toothpaste products. However, suds still improve the cleaning properties of some products, creating a cleaning experience that many people prefer. Most of these products are inexpensive, effective, and non-harmful, although they may irritate sensitive skin. Many people choose to use foaming agents in products they will use and rinse away, and avoid them in products that they will wear on the skin over time.
The future of household cleaning and personal hygiene requires products that are safe, effective, and healthy for the home and environment. The next generation of innovators is finding new ways to meet those needs, and Grapefrute recruits the talent to make it happen. Contact us today to find the best innovative candidates in-home care and hygiene.
