One of the most confusing and misunderstood topics when it comes to making cosmetics and other homemade products, knowing how and when to use preservatives is an important part of making things yourself.
Over the course of the last several years, I have gotten many and a wide variety of questions about how to preserve homemade products, and what natural preservatives can (should) be used.
With the rise in awareness about possible toxins or irritants in many of our foods, cosmetics, and even medicines, more and more people are looking for natural and/or organic alternatives.
I, myself, am one of those people. I like to make my own food and cosmetics to control the quality of the ingredients. I also like to make sure that my products don’t have certain ingredients that I choose to avoid. By making products myself, I can ensure that.
When you make your own products, you are normally trying to make something that is safer. Unfortunately, you can’t just mix whatever you want together and automatically expect to have a safe product, even if all of the ingredients themselves are free of toxins.
Why use a preservative?
Toxic ingredients aren’t the only danger that can be lurking in our cosmetics.
Microbes can also form there, whether those cosmetics are homemade or not!
The main microbes that we need to worry about when making our own products are bacteria, yeasts, and fungi such as mold. Mold is normally quite obvious to see, making it easy to tell when you should toss a certain product affected by mold growth.
Bacterial growth can be invisible
On the other hand, bacteria can form and proliferate without us being able to see them. A normal looking drop of water can have thousands (millions?) of bacteria.
While not all bacteria are harmful, some of the bacteria that can form in our homemade cosmetics can cause infections and can make our skin break out. Bacterial infections can cause folliculitis, which many people could wrongly attribute to acne or allergic reactions.
It can even become more serious than that, though. The bacteria that form in our cosmetics could make us deathly ill.
You want to take special care when making cosmetics that will be used around the eyes or any other sensitive areas. Bacteria in eye care products can cause eye infections or even blindness! (That’s why it’s always a good idea to change out your mascara or liquid eyeliners often, even if you haven’t used them all up!)
When do you need to use a preservative?
This may be the most important question!
There is a lot of confusion about when and why to use preservatives. Not all homemade products necessarily need preservatives. In fact, in some cases, it isn’t effective to use your normal preservatives.
Water-based ingredients
Any time you add water-based ingredients to a recipe, the resulting product will be more prone to microbial growth.
Generally, water-based products or any product with water-based ingredients in it will need a preservative of some type.
This is especially true of emulsions in which you are blending together oil-based ingredients with water-based ingredients or mixtures of mostly water-based ingredients.
When does a water-based product NOT need a preservative?
There are, however, a few exceptions to the “Water-based products need a preservative rule.”
Soaps and liquid soaps
I often get asked about what preservatives to use in liquid soaps. While this is a bit of a controversial topic, these are my thoughts…
True soaps and liquid soaps (those soaps made with lye) are usually self-preserving. They do NOT normally need a preservative, making them exceptions to the water rule.
It is unusual for pathogenic bacteria (the kind that can do us harm) to grow in liquid soaps because they naturally have a very high pH (generally 9-10 or higher).
Any time you have a product with an extreme pH, it becomes an environment that is less hospitable to most microbes. Yes, there are some acid-loving or alkaline-loving bacteria and other microbes that exist, but they aren’t commonly a problem with homemade cosmetics and other products. Normally, you can keep a liquid soap safely diluted for up to a year without any problems.
Bar soaps and undiluted liquid soap pastes can be kept for even longer and they will usually start to smell off or go rancid before there is any worry of problems due to bacterial growth or mold.
Syndet bars or homemade shampoos and shower gels are not true soap. Their pH tends to fall in a more neutral range so they will need a preservative if water is one of their ingredients.
Preservatives for liquid soap
The problem with trying to preserve liquid soap is that most of the preservatives on the market are ineffective at the high pH of soap. There are very few exceptions.
If you are set on using a preservative for your liquid soap, these are my recommendations:
- Add the preservative at the time of dilution. The soap paste itself has a very low liquid content and keeps very well.
- Use a preservative whose effective pH range includes the pH of your homemade soap.
From my research, this preservative seems to be the best bet for liquid soap (and appears to be safe and paraben-free)…
Suttocide™ A (INCI: Sodium Hydroxymethylglycinate): A synthetic broad-spectrum preservative derived from Glycine with a pH of 10-12. It’s active in a pH range of 3.5-12.
I’ve seen Germall Plus and Glydant plus recommended for use in liquid soaps, but their recommended effective pH range is lower than that of most liquid soaps. Glydant Plus looks a bit more promising, but the pH range cited for Germall Plus is only 3-8.
Glydant Plus (INCI: DMDM Hydantoin & Iodopropynyl Butylcarbamate (IPBC)): A broad-spectrum preservative that is effective in a pH range of 3-9. As some soap has a higher pH, it’s debatable if this preservative would actually be helpful for use in most liquid soaps.
Products with extreme pH’s
Soap isn’t the only water-based product that doesn’t need a preservative. Products with an extreme pH (below 4 or over 9), will not be as prone to microbial growth. (That doesn’t mean that you can fill them with ingredients prone to growth and be safe. More about that below…)
That’s why you may see some products offered for sale without a preservative in their ingredient list.
When working on a MIY version of a cleaner once for a reader, we noticed that there was no preservative listed for the product. We also noticed that the product had a rather high pH. She contacted the company and they confirmed that the high pH of the product was what was being used to keep their product free of pathogenic microbes.
Since then, I have made many batches of my homemade laundry detergent. While I used to bring the pH into an effective range for my preservatives, I have lately been preserving it by increasing its pH to around 10 with a solution made with water and sodium hydroxide (NaOH, commonly known as lye).
While I haven’t done any microbial testing, it appears to work quite well. It’s been a very easy-to-use, inexpensive way to keep my detergent clean and clear.
Do anhydrous products need a preservative?
What is an anhydrous product?
Anhydrous products are those that do NOT include water (or water-based ingredients). They are oil-based products that include liquid oils, solid oils, butters, and waxes.
Generally, oil-based products like homemade body butters or homemade lotion bars don’t need preservatives. Without the addition of water, they just aren’t prone to microbial growth.
There are exceptions, though, and cases where you will want to consider using a preservative in an oil-based product.
Anhydrous products and humidity
Just because a product doesn’t have water as one of the ingredients, doesn’t mean that water won’t eventually be incorporated into it.
Oil-based products meant to be used in the shower are especially likely to be “contaminated” with water or humidity. That’s why I recommended that you use a preservative when making my emulsified sugar scrub.
Sugar scrubs don’t normally have water as one of the ingredients. They are, however, normally used in the shower. People take their wet hands and scoop out some of the product and rub it all over their wet arms and legs. They then reach back in and scoop out some more.
Even if you were to carefully scoop out the product with a clean spoon each time, the likelihood of water or humidity getting into the container is quite high. Moisture that condenses on top of the product can form mold or can be the perfect medium for other microbial growth.
What is a “Natural” preservative?
There are many ways to define what a “natural preservative” is, so I’ll give you my definition.
Natural preservatives are those that can be used in products with a “natural” or “organic” certification because they use ECOcert certified ingredients. (There are other similar certifications, but for the sake of keeping things simple, I chose one and stuck with it.)
These preservatives have been developed to replace parabens and preservatives with formaldehyde or other ingredients that many people, looking for safer alternatives, want to avoid in their cosmetics.
In an effort to use more natural ingredients, though, some people look to natural ingredients that aren’t protecting us adequately.
When talking about preservatives, we need to use broad-spectrum preservatives, those that will inhibit the growth of a variety of unwanted bacteria and molds.
Natural “preservatives” that aren’t effective
Vitamin E
Vitamin E is not a broad-spectrum preservative.
It is sometimes referred to as a preservative because it can extend the shelf life of certain products. Vitamin E is an antioxidant that helps extend the shelf life of oil-based ingredients. It won’t, however, ward off microbial growth in ingredients with water-based ingredients.
How to use it:
I add vitamin E to most of my homemade lotions, oils, and butters at around 0.5% of the product by weight to help protect the oils from oxidation, thus extending the shelf life of my products.
Essential oils
Many essential oils like tea tree, oregano, rosemary, and thyme do display anti-microbial properties. They are not considered to be effective broad-spectrum preservatives, though; at least not in the sense that you could use them alone to protect your homemade lotions and other products.
Unfortunately, in most cases, you would need to use much too high of a concentration of them in your product for them to be considered safe to use as preservatives. At high percentages, many essential oils can be irritating to the skin. They also cause allergic reactions in many people.
How to use them:
While I don’t use them as preservatives, I do often add essential oils at around 1-2% of the recipe by weight to add a natural fragrance and other beneficial properties.
Rosemary extract
Like vitamin E, rosemary extract is another antioxidant that can help extend the shelf life of oils by preventing their oxidation. It also adds a pleasant aroma to soaps, oils, and butters.
Rosemary extract isn’t just useful for extending the shelf life of cosmetics, though. It is also used to extend the life of many food products.
While it is a wonderful product, it can’t be used alone as a broad-spectrum preservative.
How to use it:
Rosemary extract can either be added at around 0.15-5% by weight directly to your oils or to the oil phase of a recipe to help extend the shelf life by protecting against oxidation of the fats.
Grapefruit seed extract
INCI: Citrus grandis (grapefruit) seed extract
Grapefruit seed extract is often promoted as a very natural broad-spectrum preservative, but there is a lot of controversy about if it could actually even serve as such. While it may show some antimicrobial activity, there are several problems with using grapefruit seed extract as a preservative.
Grapefruit seed extract varies highly from supplier to supplier. Depending on the extraction method, it may be contaminated with other chemicals like triclosan which may be the ones that are actually giving the product their antimicrobial properties.
Grapefruit seed extract on its own probably isn’t going to be enough to actually preserve any homemade product.
There just isn’t enough trustworthy information out there backing the use of GSE as a preservative.
With the risk of it being contaminated with other chemicals, and little evidence that it can even work as a preservative, I definitely do NOT recommend trying to use grapefruit seed extract as such.
Common natural broad-spectrum preservatives
Alcohol
While it may not be the ideal preservative for using in lotions or shampoos, having a high enough concentration of alcohol will prevent microbial growth in homemade formulations. It also has the added advantage of being able to solubilize essential oils.
The fact that it can both solubilize and preserve makes alcohol the ideal choice for incorporating essential oils into water in products like linen sprays.
Alcohol is also great for making tinctures. By infusing plant material into the alcohol, it helps extract many of the plant’s beneficial properties.
- For solubilizing, you want to use a strong alcohol; as near to 100% alcohol content as possible. As the percentage goes down, the amount of solubilization will also decrease. (You’ll want a minimum of 75%.)
- For preserving and extracting, you’ll want to use an alcohol with at least a 40% alcohol content. Generally, tinctures and extracts like homemade vanilla extract or homemade bitters will use an alcohol with an alcohol content of at least 40%.
- A good goal for making safely preserved homemade sprays is to have around 20-30% of the final formula be alcohol. That means that if you are using an alcohol with 95% alcohol content, formulate the recipe so that around 1/4th of the mixture will be that alcohol. If you are using an alcohol with a lower alcohol content, you can increase the amount used accordingly.
Glycerin
As with tinctures made with alcohol, glycerin can be used to extract the flavors, aromas, and/or the beneficial properties of certain plants and preserve them. These extractions are called glycerites.
In most cases, you won’t want to preserve a homemade product with glycerin as glycerin needs to be used in very high percentages to effectively preserve it. Also, glycerin, while a great humectant, tends to make a product feel sticky at concentrations over 5%.
To preserve with glycerin, you’ll want to use a concentration of at least 55%.
Leucidal® Liquid SF
Leucidal is a radish root ferment that appears to be a completely natural preservative. Antimicrobial peptides are derived from Leuconostoc kimchii, the lactic acid bacteria that are used in making kimchi, a Korean fermented cabbage.
It seems like an especially ideal preservative, not only because of how natural it is, but because peptides have been found to help moisturize the skin.
When I first started making lotions, I recommended using Leucidal because I knew that many people are afraid of using “preservatives” and were looking for products that were as natural as possible. I used it without (apparent) issues.
The only thing I didn’t really like about it was the fact that when used alone, it needs to be used at a higher percentage by weight (3-4%) than the other preservatives I normally use (0.5-1%).
With time, though, I became concerned about two issues with Leucidal.
First, I had read in several places that Leucidal wasn’t as effective against molds. (Honestly, to me, that wasn’t as concerning as one can normally see mold and know to throw an affected product away.) I never had problems with mold forming in anything I made with Leucidal, though.
More concerning was the fact that a study came out that put into question what is actually preserving the products made with Leucidal. The study concluded that it isn’t really the antimicrobial peptides of the radish extract itself, but instead from salicylic acid and didecyldimethylammonium salts found in Leuconostoc/radish root ferment filtrate samples…
“In summary, the antimicrobial activity of commercial Leuconostoc/radish root ferment filtrates (LRRFF) are attributed to salicylic acid and didecyldimethylammonium salts. Moreover, these two compounds are too deficient in 14C to be the product of recent fermentation, suggesting that they are derived from petroleum feedstock. We were unable to detect antimicrobial peptides in any sample of fermented radish root filtrate.”
J. Agric. Food Chem. 2015, 63, 11, 3053-305
So, I no longer use Leucidal. It’s not cost-effective for me, and I have too many doubts about it. You, however, are free to give it a try. ?
- INCI: Leuconostoc/Radish Root Ferment Filtrate
- Effective pH range: between 3-8, works best when the pH is under 6
- Dosage: 2-4% of the recipe by weight
- Heat stable: up to 70°C
- ECOcert approved? Yes!
Sharomix™ 705
Sharomix™ 705 is another natural broad-spectrum preservative. I’ve been using it a lot lately as I can obtain large quantities at a good price.
- INCI: Benzoic acid, sorbic acid, dehydroacetic acid, and benzyl alcohol
- Effective pH range: Product must have a pH lower than 6 (lower than 5.5 even better)
- Dosage: Use at 0.6 – 1.2 %
- ECOcert approved? Yes!
Note: Sharomix is heat stable up to 80ºC, but shouldn’t be kept at high temperatures for a prolonged time.
Preservative ECO / Geogard® ECT
Preservative ECO offers broad-spectrum protection against bacteria and mold. It does impart an odor to products that some people don’t like. That can be camouflaged by the use of essential oils or other fragrances.
- INCI: a blend of benzyl alcohol, salicylic acid, glycerin, and sorbic acid
- Dosage: It is normally used at 1%.
- Effective pH range: pH3-pH8
- Solubility: It is water-soluble, but can also be used in anhydrous products like sugar scrubs.
- ECOcert approved? Yes!
Warning
Because it contains salicylic acid, it shouldn’t be used in leave-on products for babies (but can be used in rinse-off products like gels and shampoos for them).
Geogard ® 221 (aka. Cosgard)
Cosgard is another natural preservative that I have used in the past without any apparent issues. It’s an amber-colored, water-soluble liquid.
- INCI: Benzyl Alcohol (and) Dehydroacetic Acid
- Effective pH range: between 2-6, works best when the pH is under 5.5
- Dosage: 0.2-1% of the recipe by weight (Max. 1.15%)
- Solubility: water-soluble
- ECOcert approved? Yes!
Rokonsal™ BSB-N
Rokonsal™ BSB-N is a viscous colorless liquid that is generally considered a mild broad-spectrum preservative.
- INCI: Benzyl Alcohol, Glycerin, Benzoic Acid, Sorbic Acid
- Effective pH range: Under 5.5
- Dosage: 0.2-1% of the recipe by weight
- ECOcert approved? Yes!
Euxyl® K 903
Euxyl® K 903 is a very gentle, yet effective preservative, making it an ideal preservative for products that will be used around the eyes or for products like baby wipes or other baby products. It’s particularly effective in nonionic products, but also works in cationic or anionic products.
- INCI: Benzyl Alcohol, Benzoic Acid, Dehydroacetic Acid, and Tocopherol
- Effective pH range: 3-6 (Around 5-5.5 is ideal)
- Dosage: 0.2-1% of the recipe by weight
- Solubility: 100g of water at 20°C will dissolve 1.2g of Euxyl. It is NOT suitable for anhydrous products
- ECOcert approved? Yes!
Dermorganics® 1388
Dermorganics® 1388 is a colorless preservative with a mild scent. It works in a very limited pH range, so it’s important to test the pH of the product you’re making if you want to use it.
- INCI: Glycerin, Aqua, Sodium Levulinate, Sodium Anisate
- Effective pH range: 5-5.5
- Dosage: 2-4% of the recipe by weight
- ECOcert approved? Yes!
Can I substitute one preservative for another?
In most cases, you should be able to substitute the preservative that is called for in a certain recipe with another preservative that you already have on hand. There are a few things to keep in mind, though, before doing a direct switch.
Using the proper dosage
When substituting one preservative for another, don’t automatically use the amount called for in the recipe.
Instead, look at the recommended dosage for the preservative that you want to use instead. In most cases, dosages for common broad-spectrum preservatives fall around 0.5-1% of the recipe by weight. So, substituting one for another doesn’t normally greatly change a recipe.
On the other hand, some preservatives like Leucidal or Dermorganics need to be used at higher percentages to be effective. (Leucidal is normally used at around 3% of the recipe by weight.)
Using the proper pH
As you have seen above, each preservative has its own range of pHs in which it will be effective.
While most will be effective at a pH of 4.5-5.5, the range most commonly used for skin and hair products, it’s important to check the final pH of your product to make sure it falls into an effective pH range for your particular preservative.
Dermorganics, for example, is only effective at a pH range of 5-5.5. So, when using that particular preservative, it’s especially important to test the pH.
Also, note that many preservatives will alter the pH of your product slightly. If the final pH of your product is important, test the pH again after adding your preservative.
Making sure the preservative is water/oil soluble
While many preservatives can be used in both water-based and anhydrous products, not all can be used in either. Euxyl® K 903, for example, states that it is not suitable for anhydrous products.
As many of the preservatives are mixes of acids and alcohols, they are generally soluble in water and may also incorporate well into anhydrous products.
All of the above will work well in emulsions and products with both a water and an oil phase.
I tried to list solubility information for the various preservatives when I could find it, but in many cases, that information wasn’t listed. When in doubt, it’s best to check with your supplier.
Shelf life with preservative
So, you’ve determined that your homemade lotion will need a preservative and have chosen to use one of the preservatives that I have listed above.
But how long will your preserved product keep safely?
Microbial testing
When companies make products to sell, they are normally required to do some sort of microbial testing to ensure that their product is free of harmful bacteria and molds for a certain amount of time. (This, of course, depends on the regulations from country to country.)
When we are making the same sorts of products at home, though, we aren’t likely to spend the money on that sort of testing.
That’s why I recommend making small batches, those that will be completely used up within 2-3 months, even when using preservatives (especially the more natural ones).
Difficult to preserve ingredients
Just because you are using a preservative, doesn’t mean that your products will automatically be safe from microbial growth.
Certain ingredients will feed the microbes and make it especially difficult to properly preserve the products that include them. This includes food-type products like milks, honey, fruits, etc. Plant-based materials like freshly extracted aloe gel are also very tricky to preserve. Clays are another ingredient said to be troublesome.
When using any of the above ingredients, keep them to an absolute minimum. The higher the concentration of troublesome ingredients, the more likely your product will fail.
For products that won’t be used immediately, I suggest buying aloe that has already been preserved from a supplier rather than extracting the pulp yourself.
- Use distilled water vs. tap water when possible
- Avoid using food ingredients and plant materials, when possible (Use hydrosols and/or essential oils instead.)
- Avoid using high concentrations of clays, botanicals (like aloe), and anything that may contribute to microbial growth.
Use Good Manufacturing Practice
Another important part of making products to sell is conforming to “good manufacturing practice” (GMP).
Again, while we don’t need to follow the specification of GMP when making homemade products for ourselves, we should try to learn from those guidelines.
The hygiene employed while making homemade cosmetics will also affect their shelf life. You can’t preserve a homemade lotion and pour it into a moldy container and expect it to keep well.
- Wash your hands well or wear gloves.
- Wear your hair back.
- Sanitize workspaces, storage containers, and tools by spraying with 70º alcohol and wiping dry.
- Don’t reuse containers that can’t be properly cleaned or sanitized.
Conclusion
Hopefully, by now, you’ve learned that not all preservatives are bad! A product doesn’t have to be preservative-free in order to be considered “natural.”
Many preservatives are mild and safe and accepted in organic cosmetics.
Armed with the knowledge of how and why to use preservatives in your homemade cosmetics, I hope you feel more confident in moving forward as a true MIY-er. ?
CharleeT
After reading this page and doing some research I settled on Rokonsal BSB-N. However, I am unable to find a supplier in the US. Not even Amazon has it!!!Have you come across any suppliers in the US?
Thank you!
Tracy Ariza, DDS
Hi Charlee,
I live in Spain, so I’m not sure what’s available there. I’ve been meaning to look into better options for the US as most of my readers are from there. Sadly, the formulation classes I’ve taken are also based in the UK, so most of the ingredients have focused on things available and used most in Europe.
arfhan
hi Tracy, i would like to ask a question, i’m gonna make moisturizer spray for my skin with only 2 ingredients, 30 grams glycerin + 70 grams distilled water, is it really need a preservative or not?
Tracy Ariza, DDS
Hi Arfthan,
That’s a very interesting question, and one that I tried to research, but couldn’t find a definitive answer.
I guess, if it were me, I’d add one. This is my reasoning…
Honey is self-preserving on its own, but the second you add it to other products, it’s a nightmare to preserve. While glycerin is a bit different than honey and can preserve things at high concentrations, I’d be worried about watering it down. I think it could definitely feed microbes at a lower concentration. So, to be safe, yes, I’d use a preservative.
Dimitra Karatza
Arfhan & Tracy you may find the answer here: https://www.mezzonifoods.com/blog/is-glycerin-a-preservative/ (on the safe side I ‘d make it 75% glycerine and 25% water in order for the mix to be self-preserved)
Jordan
Hi Tracy,
Love your article! I am having trouble finding a preservative that’s good for leave-in products especially for afro-textured hair. My mixture is water oil mixture, I was wondering what are your thoughts about this? Thank you soo much.
Tracy Ariza, DDS
Hi Jordan,
It shouldn’t matter that it is a leave-in product. The above-mentioned preservatives are used for lotions and other products that are left on your skin, so they should be fine left on your hair.
When you say water oil mixture, do you mean it’s an emulsion or a bi-phase product like my salt spray? If bi-phase, you’d probably want water-soluble. If an emulsion, it probably doesn’t really matter so much.
I hope that makes sense.
Tsvety G
Hi Tracy,
I’m trying to dab into selling body scrubs and can’t figure which preservative would work best. The body scrubs I make a salt base with oils including essential oils. I also make sugar lip scrubs and I’m not sure what will work best since it is for the lips. Thank you in advance for any insight!
Tracy Ariza, DDS
Hi Tsvety,
When making products to sell, it’s probably best to do some sort of microbial testing to ensure that your product is safe. In many countries that is legally required, but not all countries (like the US- which doesn’t) do.
I think a preservative like Euxyl k900 would be a great alternative for this, but, again, I think you should have it tested (ideally after intentionally contaminating it with water, etc.) to make sure that it really works well for the shelf life you are trying to achieve. When choosing a preservative, you’ll have to take a look at the recommended dosage for that preservative. (For Euxyl, it’s 0.5-1% by weight.) With this having an emulsifier, I don’t think you’d have a problem with water-soluble preservatives either, but, again, it’s always best to test them out.
As for use for lips. To be honest, I’ve never added a preservative to my homemade lip scrubs or lip balms, but, on the other hand, I don’t sell them either. I could try to ask in one of my groups, but I’d suggest asking your supplier if whatever preservative you use is safe for use on lips. (The main concern there is that people could injest it.)
I think that one should be safe, but I’m not positive. It would be best to get confirmation from a supplier!
Riya
Hi Tracy,
I am totally new to lotion making. Doing a whole lot of reading but can’t find a definite answer to which preservative is good for lotions made for babies. I am trying to make lotion for my year old twin babies who are sensitive to almost every thing I have used commercially bought. I found this water based colloidal oats lotion formula and it has been working wonders but it suggested to use preservative eco. To avoid preservatives I just made lotion in small batches and used it up quickly but as I have to return to work I wanna make it in large batches and was honestly confused which preservative to use. Everyone explains about preservative but no one tells of it’s safe for babies. You are the first person I came across who said Euxyl® K 903 was safe for baby products. I believe I can use it for the lotion. But the whipped butter I make for them I have found condensation in the lid and jar due to temp changes. What preservative is safe to use in this case?
Tracy Ariza, DDS
Hi Riya,
Yes, Eukyl is safe for babies- as is Cosgard. They are both quite gentle.
I’m not sure I fully understand the question about the butter. Is this a body butter that only has oils and butters (and, perhaps waxes)?
Your issue is condensation on the bottle cap, but that’s probably only when you first make it, right?
You can just wait to cap it until it has fully cooled. That should solve the problem of condensation.
If it’s a product without water, there really is no need for a preservative, as long as you are careful when using it, and try not to contaminate it with water. In any case, Euxyl is a good choice for butters as it is oil-soluble.
Jenna Oleson
Hi I have been making homemade lotions and such for quiet some time now and have only ever used vitamin E gel capsules to help with preservation…..but I’m trying to make a good face moisturizer for my acnr prone skin and want to start using a preservative to enhance the shelf life of my products but I am unsure of what to use??? Can you please tell me a good universal preservative for my homemade products? Any help is very much appreciated..thank you!!
Tracy Ariza, DDS
Hi Jenna,
It’s very difficult to name a “universal” preservative as it will depend on the product you are making. That said, most of the more popular ones will work in many (most) applications. I have been using Sharomix a lot and Euxyl k903 is also great. They are very versatile. Those are easy to find in my area. Depending on where you live, you may find that other preservatives are easier for you to find.
E
Hi Tracy!
Thank you so much for all this helpful info! I’ll admit I am new and currently doing the research to create my organic herbal skin + body care line! For sprays, toners that will essentially have herbal infusions (water) with herbal oils (oils) together, what preservative would best suit this type of product that would 100% be organic and natural? I’m skeptical still about using preservatives at all although it seems like Euxyl® K 903 and alcohol are the healthiest, cleanest options.
Would you agree with that? Do you have any advice?
Thank you so much!
Tracy Ariza, DDS
Hello,
To be honest, I still need to update my posts that include only water and oils. (I’m slowly making my way through all of the older posts on my blog!) Ideally, you would need to solubilize the oils in the water. That can be done with a high-strength alcohol or with a solubilizer. Solubilizers can be mixed with the oils, and once the oils are incorporated, the mixture can be diluted with water.
If you were to use alcohol, it would serve both purposes (preserving and solubilizing) as long as you didn’t dilute it too far.
If you wanted to use Euxyl, you really should solubilize the oils into the water first, otherwise the preservative may not be protecting both the water and oil phases, if that makes sense.
Obviously, you don’t want to overuse preservatives, but if you are careful with the dosage, the more natural preservatives are definitely safer than not using a preservative. Good natural and/or organic cosmetics use them too. (Yes, both alcohol and Euxyl are acceptable for organic certification.)
Kenyce L McBride
If I use ethanol as a preservative for my infused Calendula cream. Would this preservative (ethanol) be enough or would I need two preservatives?
Tracy Ariza, DDS
Hi Kenyce,
When using ethanol as a preservative, you need to have the alcohol concentration of the final product be above 20-25%. That’s obviously not ideal for a cream as it would end up being drying to the skin.
For a cream, I’d suggest using one of the broad-spectrum preservatives available for sale on the market.
Alex
Hi Tracy, thanks for your article!
Is there a particular reason why Dehydroacetic Acid is almost always used in combination with Benzyl Alcohol and/or Benzoic Acid? Why can I not use only Dehydroacetic Acid in my formulation?
Have a great day!
Tracy Ariza, DDS
Hi Alex,
I’m sorry for the late reply. I was actually in the middle of taking a course in natural cosmetic preservatives, and wanted to finish the course before answering- in case I found a more thorough answer for you.
Really, the only thing I found was that they said that generally, you need a combination of different types of preservative components to ensure that you have broad spectrum protection. That is especially true with the more natural preservatives (that aren’t as strong as the parabens, for example.)
Generally, some of the components are good against bacteria, others are good against certain bacteria, and yet others are good against other bacteria.
Even after taking a course in it, I wouldn’t feel confident in trying to preserve something without using a pre-mixed blend. You’d have to do a lot of microbial testing on your products to ensure that they are really staying free of problematic microbes- and that can cost a lot of money.
It isn’t worth it for me.
I’d prefer to use tried-and-true preservative blends.
Jack
Hi Tracy, what is your recommendation for a natural Hyaluronic serum perservative?
Thank you
Tracy Ariza, DDS
Hi Jack! I usually use Sharomix in mine, but you should be able to use whatever water-soluble preservative that you can find locally.
Kathleen
If a recipe calls for castile soap and water, will it need a preservative?
Tracy Ariza, DDS
Hi Kathleen,
If it only has Castile soap and you are only diluting it somewhat with water (like for using in a foaming dispenser), in most cases you should be fine, at least for a while. It’s unlikely that you will be lowering the pH of it very much with only water. I wouldn’t highly dilute large amounts, though. Just dilute what you can use in a relatively short amount of time.
It’s all about the pH. It should still be higher than where most pathogenic microbes grow (and above the range where most preservatives are effective anyway.)
If you’re uneasy about it, you can try one of the preservatives I’ve mentioned for liquid soap. (But, as I said, I have personally never used one with my soaps.)
Kathleen
Tracy,
Thank you for the reply. That makes sense. Would you recommend using PH strips for lotions, soaps, etc?
Tracy Ariza, DDS
Hi Kathleen,
Yes. They work fine. You don’t really need to know a super precise measurement, so I find that pH strips work well. I talk more about testing the pH in my new post about the importance of pH in cosmetics.
Roseanna
Hi Tracy,
I’d like to know which preservative would be best for use in a lotion and is also safest on a baby’s skin. I currently have Cosgard but haven’t found any info on whether or not it’s definitively safe for babies. Since I plan on making some lotion as a gift, a skin test isn’t feasible.
Thank you!
Tracy Ariza, DDS
Hi Roseanna,
Sorry for the late response. I meant to look into it more closely and get back to you and then forgot. I found this way back with a bunch of unasnswered spam.
My supplier has it listed as a very gentle preservative (Cosgard/Geogard). They do recommend it for baby products and for body lotions recommend a dosage of 0.6-0.8%. I’m not quite sure why, but they recommend a dosage of 1.15% for facial creams. (It doesn’t make a lot of sense that you’d need more for an emulsion for your face than for your body to me.)
Ideally, yes, a product should be tested- which is especially true for items meant for others, but, of course, most of us aren’t going to test if we make a product that isn’t for sale. Just make sure that the people you give the gift to understand that you are using a natural preservative and that, while it should keep for longer than that, it’s best to use it up within 2-3 months if no testing has been done on it. 😉
Martha Jane Deitz
Do you have an opinion on Optiphen in lotions. I am researching preservatives for lotions to expand my product line. Thank you
Tracy Ariza, DDS
Hi Martha,
It seems to be more common in the Americas and Australia than here in Europe. That’s why I’ve never used it. It just isn’t a preservative I’ve seen here before. I haven’t researched it a lot, but it should be fine to use.
Dee
Hi Tracy, thanks for such valuable information.
Can I use Cosgard in an oil-glycerine (no water) body scrub?
How about in a melt and pour soap that has hydrosols added?
Do they actually need a preservative?
Thanks so much in advance. Have a lovely day!!!
Tracy Ariza, DDS
Hi Dee,
It’s difficult to comment on “melt and pour soaps” as a group in general because there is a huge variety amongst them. Some are actually real soap with other additives added to allow them to be melted. Others (most I’ve seen!) aren’t actually really soap and are really detergent bars instead.
Depending on the ingredients, their pH will probably be completely different. Real soap melt and pour soaps will have a higher pH and probably won’t need it. If you are adding water, as long as they are still hardening up into soap, they should be fine. If they are detergent bars with a low pH, adding too much extra water may throw off the preservatives they have used (which are normally dosed by weight percentage). You could check the ingredients and/ or the pH. (I talk about testing the pH in my latest post about pH in cosmetics.) If it’s a detergent bar and has a lower pH and you add too much water, you may want to add a preservative at the dosage for the amount of liquid added.
As for Cosgard in an oil-only product… I don’t think it would work, unless it’s an emulsified scrub with some sort of emulsifier. Cosgard is water-soluble. You’d need an oil-soluble preservative. (Something like Euxyl® K903 should work.)
Chozen Love Toney
Hi Tracy! Do you know anything about using citric acid as a naturual preservative?
Tracy Ariza, DDS
Hello,
Citric acid wouldn’t be a very good preservative on its own, unless you used it to bring down the pH enough to bring the product down below a pH of 3-4, making it less hospitable to microbes. That’s not generally the ideal way to preserve things, though, as extreme pH’s aren’t generally ideal for skin or hair.
The broad-spectrum preservatives on the market are generally (or all?) a combination of various different acids and other substances. Together they can better prevent a wide variety of microbes that might negatively affect your products.