How to keep creams germ-free

Bacteria, yeasts and moulds are an indispensable element of life and evolution. On one hand bacteria on our skin and in our digestive system are of high functional need, on the other hand we intend to protect our food and cosmetics against undesirable contamination. 

Killing bacteria, yeasts and moulds is less of a challenge than finding the right balance: The modern way of preserving a product means to make a product unattractive for germs but highly attractive for consumers. Such a guiding principle, however, confronts cosmetic manufacturers with typical questions for each new development: 

• Shall I use listed preservatives or other antimicrobials?
• Which substance is best for my product?
• What about the potential for irritation? 
• Is it possible that the antimicrobials interact with the other ingredients? 
• Which substances can be certified with different natural cosmetic labels?  
• Are there any restrictions regarding the allowed dosage?

In order to understand these questions and their back story, we need to dive into the history of preservation from the start and also concentrate on the fast development in the last 15 years. 

The first indications of preservation go back to 5000 B.C. when grapes were dried or used to prepare wine and vinegar. Romans mastered many preservation techniques that are still used today. Vegetables were covered by oil, fruits preserved by honey, other food was salted or boiled in salted water. In the late Roman Byzantine Empire, medicals led to the discovery of distillation; the beginning of the perfume development and the usage of alcohol for preservation. 

The development of synthetic preservatives in the 19th and 20th century led to the breakthrough of broadband preservation. In 1855, formaldehyde was discovered and ten years later a technical production was realised. In the course of the next 100 years, formaldehyde-donors such as DMDM-Hydantoin and Bronopol. In 1930, the invention of parabens had a significant influence on the market and simplified preservation a lot. These esters of p-hydroxybenzoic acid showed a great efficiency, an acceptable water-solubility, covered a broad pH range of 3.0–7.0 and were inexpensive. However, every product has its zenith and the situation changed. 

Since 1953, more and more toxicological research centres have been established and step by step put a damper on several synthetic preservatives. A couple of dangerous side effects starting from allergic reactions, hormone influencing effects right up to a carcinogenic potential were identified or the substances just came under suspicion. Today, some substances are completely banned and the use of most of the early synthetic preservatives has been restricted. Nevertheless, parabens are still used in mass market products but even large manufacturers are starting to search for alternatives. 

It seems that in the last ten years progress has sped up more than ever. Why? Scientific research, safety reports and toxicological as well as irritation tests are just some pieces of the puzzle. Test magazines, cosmetic websites and rating apps for smartphones are further powerful tools with a strong influence on consumer’s opinions and needs. Whereas in the past a certain level of chemical knowledge was necessary to understand the INCI of cosmetic products, in modern days such smartphone apps make it very easy to gain a fast and straightforward overview of substances and their individual rating. 

Nevertheless, these platforms can be unfair and misleading when they don’t handle the individual rating of raw materials transparently. As a result of these tools and growing awareness concerning chemical components, the pressure on the cosmetic producers is just as increasing as the number of new developed healthy ingredients. Even big multinationals have started to replace controversial substances. 

It seems as if for each new trend a new certification label pops up. All these labels have different requirements and it can be hard to keep track; in particular for manufacturers who export their products and thereby are obligated to fulfil local requirements of other countries. Although, today it is highly recommended to reassess especially the antimicrobial system of cosmetic formulations more than ever. 

The variety of user needs is massive: European, African and Asian skin are as different as the individual sensitivity to irritating ingredients. Companies such as ours who produce raw materials to protect cosmetic formulations against microbials, oxidation and instability are dealing with these challenges. We focus on product preservation and particularly on alternative preservation. Thanks to an international client network, the manufacturer benefits from a broad experience of global market trends and requirements. Thus, a high number of antimicrobial products meets the needs of each cosmetic product line. 

As a result of long-term research, our company has defined three possible stages to effectively replace preservatives. In the first stage, criticised preservatives can be replaced with inexpensive mixtures of well-tolerated and mild preservatives boosted by antimicrobial multi-functionals.

The second stage is represented by synthetic multi-functionals with the big advantage that they do not need to be listed as preservatives. Thus, there are no restrictions and these products can be used in all kinds of formulations and in every dosage. An impressive range of positive properties include a strong antimicrobial efficiency. 

Finally, the last stage is using completely natural preservation with the help of natural-certified antimicrobials. This broad product portfolio is a relief for every cosmetic manufacturer because many substances are offered as both a natural and as synthetic version. Once an efficient antimicrobial system has been identified, it is easy to start with the synthetic versions and replace them easily by the chemically identical natural versions if a certification is required. 

For each individual formulation the best price/efficiency ratio is identified with the help of challenge tests. 

Screening the market for new antimicrobial substances and synthesis of new molecules is part of our company’s research. But also well-established products get improved continuously for example by increasing their user-friendliness. The manufacturer’s R&D team believes: “Well-proven antimicrobials which have been used for decades without any concerns are like raw diamonds.” 

A good example for such a development is our invention of Cosphaderm Sodium LAAS: The levulinic acid derived from sugar cane and anisic acid derived from star anise, are strong organic antimicrobials which have been used in all kind of cosmetic products including baby care for the last 20 to 30 years. The challenge is the workflow and handling of these acids caused by a low solubility. Transforming them into salts combined with a spray drying process results in a new product that is far more user-friendly and also more sustainable. No further dissolution steps of the acids are needed and the concentration of actives in the mixture can be increased to a maximum. This does not only reduce packaging and transportation costs but also storage areas and makes the use of palm-oil derived solvents obsolete.

In conclusion, as natural ingredients have come more and more to the forefront in industrial countries due to the increased number of concerned and well-informed end-consumers, the green trend continues. As the growing number of certification labels and requirements within the global market are challenging for cosmetic manufacturers dependable experience is needed to help navigate through regulatory pitfalls. 

Cooperation with experts in preservation, such as our company, can help bridge knowledge gaps and workload, including expertise in how to deal with natural cosmetic labels and REACH relevant topics. 

Prospectively, new molecules and new antimicrobial extracts will be developed as we gain more knowledge about natural processes and billions of years of evolution. Nevertheless, improving existing substances to work in a more effective way is also gaining in importance. Finally, we can learn from history that the current classification is just a snapshot of the current toxicological knowledge base and it will be interesting to see what new insights the future will bring.