Preservatives in the manufacture of natural cosmetics

Preservatives in the manufacture of natural cosmetics

There are many preservatives accepted in natural cosmetics, even if the vast majority are synthetic. For the sale, the preservatives are essential for any formula composed mainly or partly aqueous body.

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Several preservatives of the cosmetics industry are harmful synthetic products, but some mimic natural molecules. They are in every way identical. Their manufacture is ecological and their use without danger, provided they respect the concentration.

The use of healthy synthetic preservatives is more ecological than the manufacture of molecules directly from nature (which would require large amounts of organic matter, which is not really viable or possible, given the quantities used) . In any case, these are the same molecules. For all these reasons, some still consider them as "natural" products. The choice of using them or not is personal. The fact remains that these are clean, safe, reliable, healthy preservatives for us and for the environment. They are approved by Écocert.

Always hold the preservatives out of the reach of children. Never swallow and avoid contact with the eyes. Always respect the recommended dosage, at the risk of causing irritation. Recommend an allergy test on the forearm for all formulas, with or without preservatives.

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The aqueous bodies of a formula are responsible for the high risks of mold and bacterial contamination. Without aqueous body, you will not need preservatives, but rather antioxidants (vitamin E, oleoresin of Rosemary) to slow down the rancid of fatty substances. The more stable an aqueous body, the more the formula will also be. We will avoid ordinary water and herbal teas, then we will promote aloe gel (which already contains preservatives) and hydrosols (although considered unstable by chemists, hydrosols allow an appreciable lifespan). Beware of sucking plants, some of which can mold creams (chamomile, oats).

We suggest promoting wide spectrum preservatives (bacteria, mushroom yeasts) to avoid unpleasant surprises. These preservatives allow an average lifespan of one year. These will be added more often in the cooling phase, after adjusting the pH. It will be important to choose a preservative depending on the pH, otherwise it might not be activated.

Large spectrum synthetic preservatives

Sodium benzoate
Sodium benzoate is a salt of benzoic acid, found naturally in several fruits such as cranberries. It is obtained by the addition of benzoic acid to a very hot solution of sodium carbonate. White granules soluble in water. Often combined with potassium sorbate.

Inci: Benzoate sodium

Antifungal, antibacterial.

pH: works at 6.0 pH and less.

Concentration: maximum 1 %, add in the aqueous phase or in the cooling phase. It is not recommended to combine it with vitamin C (risk of benzene formation, a toxic product).

Geogard Ultra
Also named Neodefend. Soluble white powder in water, composed of 75% gluconolactone (Ester of gluconic acid obtained by corn fermentation) and 25% sodium benzoate (sodium salt of benzoic acid).

Inci: gluconolactone & sodium benzoate

Antifungal, antibacterial.

pH: effective at pH between 3.0 and 6.0.

Concentration: 0.75 to 2 %, add in the aqueous phase or in the cooling phase (advised to dissolve it in water in this case).

Geogard ect

Also appointed ECO Conservative. Amber liquid with a very light almond aroma.

Inci: Benzyl Alcohol & Salicylic Acid & Glycerin & Sorbic Acid

Note that there is a restriction for children under three years concerning salicylic acid (except in shampoos and other rinsed products) in force in Europe since 2018. For this reason, we suggest favoring the use of Another preservative.

Antifungal, antibacterial.

pH: effective at pH between 3.0 and 8.0

Concentration: 0.6 to 1 %, in the cooling phase.

Potassium sorbate
Potassium salt from Sorbic acid, a fatty acid naturally present in the bays of the Sorbier. Powder or granules, white color, no smell. Potassium sorbate releases sorbic acid, its active ingredient, in water.

Inci: potassium sorbate

Antifungal, antibacterial.

pH: effective at pH between 2.0 and 6.5.

Concentration: 0.15 to 0. 3%, can be added at the end of the formulation (after adjusting the pH).

I personally used potassium sorbate for years with excellent results. For the cost, it is a simple and effective preservative. You really have to respect the dosages because it can make an irritating product. It allows emulsions of about a year. After a year and two months the cream is contaminated by bacteria. This is not visible to the naked eye and the smell remains the same, but the cream causes the appearance of pimples on the skin of the face. So I advise to throw the cream after a year.

Large spectrum natural preservatives
The preservatives 100 % are few, overpriced or inaccessible. Here are two that you can easily get yourself, although you will have to pay them more.

Dermasoft Pentiol Eco
Designed by the German company Evonik of Dr Straetmans, specialists in healthy natural preservatives for us and for the environment. 100% natural preservative certified without synthetic and versatile preservatives, from sugar of non-ripe juice of beet. Clear and odorless liquid, water-soluble, dermocaustic and irritating (attention).

Inci: Pentylen Glycol

Antibacterial and antifungal.

PH: Effective regardless of pH!

If you calculate the pH of your product, it is possible that it changes with the addition of this preservative. Do not panic, the pH will return to normal after maximum 2 hours (often after 10 minutes).

Concentration: 1 % to 5 %. The more your formula contains water, the more you will have to put it in large quantity. However, you should not exceed 5%. We suggest putting less in formulas intended for facial care (more sensitive skin). Reduce the quantity if it is combined with another preservative.

Personally this is my favorite curator! Liquid, it is easily added in the cooling phase (be sure to wear gloves), even in a cold cream made for a few days. According to the distributor, it keeps emulsions for two years! I suggest planning rather a year and a half, because the results vary from one formula to another. It is designed to operate regardless of pH (practical!) And no matter the formula (water cream in oil or oil in water, aqueous formulas, shampoos, etc.). Versatile and 100 % natural! It's worth paying a little more.

Also named Naticide. 100% natural preservative from aromatic vanilla and almond extracts (watch out for allergies). Pale yellow fluid fluid liquid with sweet aromas. Insoluble in water, soluble in oil and alcohol.

Inci: fragrance

These are aromatic compounds. The exact composition is protected by a patent.

Antibacterial and antifungal.

PH: effective at pH between 4.0 and 9.0, interesting for eye contour creams (pH of 7.0).

Concentration: 0.3 to 1 %, must be added at the end of the recipe, cold, and must be well stirred to allow its dissolution everywhere in the formula.

Antimicrobial curators
The following preservatives are rather co-preservatives because they are not antifungal and do not allow, alone, to prevent mold and yeasts in the formulas containing water.

Grapefruit seed extract (EPP)
Antibacterial orange liquid from seeds, pulp and white membrane of the grapefruit. There are several kinds of EPPs, favoring the 40 % vegetable glycerin compound extract. Inci: Citrus grandis (grapefruit) Extract and glycerin


Concentration: 0.2 to 2 %, add in the cooling phase.

There is a controversy regarding the EPP. Some argue that studies have demonstrated carcinogenic effects and that the antibacterial effect would not be due to the EPP but rather to the additives it contains. We did not find any studies confirming this for cosmetic use or for glycerin -based extract. It goes without saying that we advise everyone to do their own research.

Clear and odorless liquid, 100 % natural, extract from the fruit of black elders. Liposoluble.

Inci: sambucus nigra fruit extract


Concentration: 1 to 5%. As it is soluble in fats and not in water, it will be added to the oily phase of a formulation or in the cooling phase.

PH: more effective in a formulation with a pH located between 3.0 and 8.0. Remains stable up to 75 degrees C and is

Some sources mention its antifungal properties. Note that these are not strong enough to prevent mold and yeasts and that an emulsion will be quickly contaminated if we use that this preservative.

Other preservatives
We do not recommend the use of the following preservatives, although they can find themselves in some partly natural cosmetics and sometimes be accepted by certification bodies organic.


Inci: Leuconostoc / Radish Root closes filter

Antibacterial, would also be antifungal.

PH: Effective at pH of 9.0 and less.

We have not found sufficient evidence of its effectiveness and its natural composition (which is proclaimed). We put it to the test and have obtained poor results: mold after only 2 months for formulas that potassium sorbate can easily keep a year. A Japanese study has demonstrated the little antifungal effect of this product.

Germall plus

Inci: Propylene Glycol (and) Diazolidinyl urea (and) iodopropynyl butylcarbamate


Inci: urea of ​​diazolidinyl, methodylparaben, propylparaben, propylene glycol


Inci: Phenoxyethanol, methodylparaben, butylparaben, ethylparaben, propylparaben

Diazolidinyl urea contains formaldehydes.

Phenoxyethanol is a glycol ether which can induce neurotoxic effects and neurological disorders (it passes the dermis and even the placenta). Could be aware and irritating. Nocif if ingested, it can cause irritation in the eyes and the respiratory system.

Propylene Glycol is an alcohol from the petroleum industry. It is moistening like glycerin, but turns out to be irritating in certain subjects. In addition, its manufacture is not ecological.

These products, except leukidal, are well-known endocrine disruptors. We do not recommend them given their high toxic potential.

Conclusion on the preservatives
It is quite possible to keep our creams for a year, which is sufficient and very appreciable. We work with living products and hope that they remain it.

To avoid contamination, in addition to using healthy preservatives, make your products in small quantities to offer products that are always fresh to the customer.

You will of course have to clean (disinfect, abuse, sterilize in some cases) your material, your workspace and your containers.

* Little last minute addition :) The Curator Optiphen contains phenoxyethanol, to be avoided.

See preservatives On the shop Les Âmes Fleurs.

Marie-Christine Vallières, herbalist and manufacturer

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  • Marie-Christine Vallières