[Alex777]

@Pharma

Your responses are so detailed and helpful! Thank you!

I am concerned about mass vs volume measurements for alcohol because they say 20% is usually enough to be used a preservative and want to make sure they are referring to the volume weight because the difference is significant between the mass and volume of alcohol. 

I guess we will try the 25% glycerin by mass and about 12-15% ethanol by volume. 

Hopefully this is enough to pass the stability testing.

Thanks again!!!

[Alex777]

@”Dr Catherine Pratt”

Thank you. However, it was my understanding that when formulating everything must be measured by volume because every liquid/solid has a different density. 

I just wanted to confirm if this is true. 

[Alex777]

One last thing, sorry! I know I said that multiple times now

When calculating glycerin in the formula, you must count it by volume and not by mass correct? 

By mass we are using 25% glycerin, but by volume it’s only 20%.

Just want to confirm. 

Thank you!

[Alex777]

@Pharma
thank you for your help!

[Alex777]

@Pharma 
Thank you for your help! Really appreciate it!

I wonder how low we can go with alcohol if there is already a 20% glycerin concentration. 

[Alex777]

@Pharma @Dr Catherine Pratt

Thank you both so much!

If you don’t mind me asking just one more question:

would adding sodium bicarbonate and aloe Vera make it impossible to preserve using the essential oils listed above? 

I apologize for all the questions. Thank you again!

[Alex777]

@Cafe33 Thank you! Appreciate your help

[Alex777]

@Pharma

Thank you so much for your help, Pharma! It is greatly appreciated! 

I’m sorry for bothering you, but may I please ask you this last question:

There is a product that preserves their mouthwash using only essential oils. They are a reputable company and have been around for over 2 decades. 

Here is their ingredient list: 

Deionized water, vegetable glycerine, extracts of echinacea angustofolia, echinacea purpurea, gotu kola, pure essential oils of peppermint, red thyme, cinnamon bark, eucalyptus globulus and lavender, plant saponins.

How are they able to preserve using essential oils? All the chemists on here say that essential oils do not and cannot work.

Just want to hear your thoughts on this. 

Thank you again so much for your help!

[Alex777]

@Pharma

Thank you so much for your detailed response! 

Do you think we should just stick with the 20% ethanol and call it a day? We also use 20% glycerin.

Do you think that we can drop ethanol to 15% considering we use glycerin at 20%? 

Thank you again! Really appreciate your help

[Alex777]

Thank you for your input.

Would Quillaja saponaria work to dissolve essential oils in water?

If so, can you please provide an approximate use percentage?

Thanks again

[Alex777]

@paoloferino

Thank you for your thoughts!

Is there any other more “natural” way of getting this done?

[Alex777]

Also, does sodium bicarbonate lower water activity?

[Alex777]

@Pharma 

Thank you for your input. 

Just to confirm, if using 20% glycerin, only 10% of ethanol is needed to preserve?

I assumed the following:

If I have a solution that is 454mL. 20% of that solution is glycerin (91mL). 

454mL - 91mL = 363mL 

I assumed I would use 

363mL x 20% Ethanol = 73g Ethanol. 

In your case, I would be using 45.4g ethanol.

(454 x 10% Ethanol = 45.4g)

Can you confirm which volume of ethanol would be appropriate here?

Thanks!

[Alex777]

@natzam44 Thank you for letting me know. I think as many of the previous users have mentioned, the best “natural” route would be ethanol. 

I have experimented with 20% ethanol and it works well in the formula. Adds some mild burning but nothing close to Listerine. 

Would you mind me asking what products you formulated that failed with Plantservative? I don’t need to know details jus curious if it was a cream based product or a liquid formulation.

Thanks again! 

[Alex777]

Thank you again for everyone who contributed to this post!

I just have a few questions as I am understanding natural preservatives are not sufficient. 

1. How much ethanol is required to preserve a product? Can you use under 20%? Under 15%?

2. Will a combination of 10-15% glycerin and 10-15% alcohol have a synergistic effect in regards to preservation? 

3. Is a pH of 10 sufficient enough to preserve a formulation?

4. Below I have listed 3 separate, completely natural formulas. How are these products claiming to have a 2-year shelf life with no preservatives on their labels?!

A. Purified, deionized, microfiltered water and ten parts per million of silver mineral (99.000% pure), calcium carbonate (natural chalk), sea salt, mustard seed powder, magnetic earth, active ionic minerals, essential oils of peppermint, eucalyptus, clove, wintergreen, and oregano.

B. Deionized water, vegetable glycerine, extracts of echinacea angustofolia, echinacea purpurea, gotu kola, pure essential oils of peppermint, red thyme, cinnamon bark, eucalyptus globulus and lavender, plant saponins.

C. Aloe barbadensis (inner leaf) juice, vegetable glycerin, cocos nucifera (coconut) oil, xylitol, mint (mentha piperita & spicata) leaf oil, mentha arvensis (menthol) crystals, ocimum sanctum (tulsi) leaf extract, azadirachta indica (neem) extract, calcium ascorbate (vitamin C), stevia rebaudiana (stevia) leaf/stem extract, sodium chloride (sea salt), activate (coconut) charcoal. 

Hoping to hear from all of you!

Thanks! 

[Alex777]

Hi Cafe33,

Thank you so much for sharing that information!

To be honest, it is hard to believe that a 6.5% ethanol concentration is enough to preserve a mouthwash. I thought 20% was the minimum?

[Alex777]

Hi natzam44,

Thanks for your input. 

At what concentrations did you use Plantservative?

Thanks,
Emil 

[Alex777]

Thank you EVchem and Dr. Catherine Pratt for your responses!

Dr. Catherine Pratt, did you mean Leucidal and AMTicide Coconut? I believe the Amticide is for additional fungal protection, right? 

Thanks again for your input!

Seems like no one has faith in Plantservative (Japanese Honeysuckle)?

[Alex777]

Thank you Gunther and Pharma for your input. 

Pharma, do you believe that a 20% glycerin concentration would have any preserving effects or would you need a minimum of 30% to see any preserving properties?

Gunther, we do not want to incorporate parabens into our formulation. We want to go as natural as possible. 

Thanks again!

[Alex777]

Hi Pharma,

Thanks for responding to this post!

The mouthwash is a ready to use formula. 

I want to avoid alcohol because there are several studies that show it is detrimental to oral health. Also because of the stinging, burning and bitterness. 

I agree with the pH of 10 being too harsh on the oral tissue. 

There are a few companies that are mixing essential oils (cinnamon, thyme) with glycerin and are excluding preservatives. 

However, they might not be providing full disclosures of their product labels.

Listerine uses 21% alcohol, plus essential oils, plus sodium benzoate, so it is hard to believe that essential oils blended in with glycerin will actually preserve a product for 12+ months. 

[Alex777]

Hi EVchem,

Thanks for responding to this post!

There is currently no alcohol in the mouthwash. I want to avoid it because of the negative health effects it has. Alcohol also gives a strong bitter flavor and burning sensation to the mouthwash.