Essence Formulation Review: Preservation and Compatibility

Question

Regarding an Essence formulation:

[url=https://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B9%88%E0%B8%A7%E0%B8%99%E0%B8%9B%E0%B8%A3%E0%B8%B0%E0%B8%81%E0%B8%AD%E0%B8%9A%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%AA%E0%B8%B3%E0%B8%AD%E0%B8%B2%E0%B8%87%E0%B8%84%E0%B9%8C/143-glycerin-%E0%B8%81%E0%B8%A5%E0%B8%B5%E0%B9%80%E0%B8%8B%E0%B8%AD%E0%B8%A3%E0%B8%B5%E0%B8%99.html:6rkvva4w]Glycerin[/url:6rkvva4w] 99.5% 5%
[url=http://www.myskinrecipes.com/shop/%E0%B9%80%E0%B8%9B%E0%B9%8A%E0%B8%9B%E0%B9%84%E0%B8%97%E0%B8%94%E0%B9%8C%E0%B8%A5%E0%B8%94%E0%B8%A3%E0%B8%B4%E0%B9%89%E0%B8%A7%E0%B8%A3%E0%B8%AD%E0%B8%A2/762-madecassoside-centella-asiatica-extract.html:6rkvva4w]Madecassoside[/url:6rkvva4w]-80 ([url=http://www.myskinrecipes.com/shop/%E0%B9%80%E0%B8%9B%E0%B9%8A%E0%B8%9B%E0%B9%84%E0%B8%97%E0%B8%94%E0%B9%8C%E0%B8%A5%E0%B8%94%E0%B8%A3%E0%B8%B4%E0%B9%89%E0%B8%A7%E0%B8%A3%E0%B8%AD%E0%B8%A2/762-madecassoside-centella-asiatica-extract.html:6rkvva4w]Centella Asiatica Extract[/url:6rkvva4w]) 1%
[url=https://www.myskinrecipes.com/shop/search?search_query=salicylic+acid&orderby=position&orderway=desc:6rkvva4w]Salicylic Acid[/url:6rkvva4w] ([url=http://www.myskinrecipes.com/shop/%E0%B8%A3%E0%B8%B1%E0%B8%81%E0%B8%A9%E0%B8%B2%E0%B8%AA%E0%B8%B4%E0%B8%A7/148-salicylic-acid-bha-%E0%B8%81%E0%B8%A3%E0%B8%94%E0%B8%8B%E0%B8%B2%E0%B8%A5%E0%B8%B4%E0%B9%84%E0%B8%8B%E0%B8%A5%E0%B8%B4%E0%B8%81.html:6rkvva4w]BHA[/url:6rkvva4w]) กรดซาลิไซลิค 2%
[url=http://www.myskinrecipes.com/shop/%E0%B8%95%E0%B8%B1%E0%B8%A7%E0%B8%97%E0%B8%B3%E0%B8%A5%E0%B8%B0%E0%B8%A5%E0%B8%B2%E0%B8%A2/838-%E0%B8%99%E0%B9%89%E0%B8%B3%E0%B8%81%E0%B8%A5%E0%B8%B1%E0%B9%88%E0%B8%99%E0%B8%9A%E0%B8%A3%E0%B8%B4%E0%B8%AA%E0%B8%B8%E0%B8%97%E0%B8%98%E0%B8%B4%E0%B9%8C.html:6rkvva4w]น้ำกลั่น[/url:6rkvva4w] 67.7%
[url=http://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B9%88%E0%B8%A7%E0%B8%99%E0%B8%9B%E0%B8%A3%E0%B8%B0%E0%B8%81%E0%B8%AD%E0%B8%9A%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%AA%E0%B8%B3%E0%B8%AD%E0%B8%B2%E0%B8%87%E0%B8%84%E0%B9%8C/184-disodium-edta-2na.html:6rkvva4w]Disodium EDTA[/url:6rkvva4w] 0.2%
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/1199-yeast-radiance-%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%84%E0%B8%A7%E0%B8%B2%E0%B8%A1%E0%B8%81%E0%B8%A3%E0%B8%B0%E0%B8%88%E0%B9%88%E0%B8%B2%E0%B8%87%E0%B9%83%E0%B8%AA%E0%B9%81%E0%B8%81%E0%B9%88%E0%B8%9C%E0%B8%B4%E0%B8%A7.html:6rkvva4w]Yeast Radiance™[/url:6rkvva4w] 3%
[url=http://www.myskinrecipes.com/shop/%E0%B8%A1%E0%B8%AD%E0%B8%A2%E0%B8%8B%E0%B9%8C%E0%B9%80%E0%B8%88%E0%B8%AD%E0%B8%A3%E0%B9%8C/404-double-hyaluron-liquid.html:6rkvva4w]Hyaluronic Acid[/url:6rkvva4w] (Japan) 0.8%
[url=http://www.myskinrecipes.com/shop/%E0%B8%A1%E0%B8%AD%E0%B8%A2%E0%B8%8B%E0%B9%8C%E0%B9%80%E0%B8%88%E0%B8%AD%E0%B8%A3%E0%B9%8C/404-double-hyaluron-liquid.html:6rkvva4w]Double Hyaluron Liquid[/url:6rkvva4w] 5%
[url=https://www.myskinrecipes.com/shop/%E0%B8%84%E0%B8%A7%E0%B8%B2%E0%B8%A1%E0%B8%8A%E0%B8%B8%E0%B9%88%E0%B8%A1%E0%B8%8A%E0%B8%B7%E0%B9%89%E0%B8%99%E0%B8%9C%E0%B8%B4%E0%B8%A7-moisturizer/8180-snow-mushroom-hyaluron.html:6rkvva4w]Snow Mushroom Hyaluron[/url:6rkvva4w] 0.3%
[url=https://www.myskinrecipes.com/shop/%E0%B8%A5%E0%B8%94%E0%B8%81%E0%B8%B2%E0%B8%A3%E0%B8%AD%E0%B8%B1%E0%B8%81%E0%B9%80%E0%B8%AA%E0%B8%9A%E0%B8%82%E0%B8%AD%E0%B8%87%E0%B8%AA%E0%B8%B4%E0%B8%A7/7387-succinic-acid.html:6rkvva4w]Pure-Succinic™ (Succinic Acid, High-Purity)[/url:6rkvva4w] 2%
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/1140-tranexamic-acid-%E0%B8%97%E0%B8%A3%E0%B8%B2%E0%B9%80%E0%B8%99%E0%B8%8B%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%84-%E0%B9%81%E0%B8%AD%E0%B8%8B%E0%B8%B4%E0%B8%94.html:6rkvva4w]Tranexamic Acid[/url:6rkvva4w] 3%
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/1213-4msk-potassium-methoxysalicylate.html:6rkvva4w]4MSK (Potassium Methoxysalicylate)[/url:6rkvva4w] 2%
[url=https://www.myskinrecipes.com/shop/%E0%B8%81%E0%B8%B1%E0%B8%99%E0%B8%AD%E0%B8%99%E0%B8%B8%E0%B8%A1%E0%B8%B9%E0%B8%A5%E0%B8%AD%E0%B8%B4%E0%B8%AA%E0%B8%A3%E0%B8%B0-%E0%B9%81%E0%B8%AA%E0%B8%87-uv/7752-activeprotec-ox.html:6rkvva4w]ActiveProtec™ OX[/url:6rkvva4w] 1%
[url=http://www.myskinrecipes.com/shop/%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%89%E0%B8%B2%E0%B8%99%E0%B8%A3%E0%B8%B4%E0%B9%89%E0%B8%A7%E0%B8%A2%E0%B8%AD%E0%B8%A2/74-vitamin-b3-niacinamide-%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%9A%E0%B8%B53.html:6rkvva4w]Safe-B3[/url:6rkvva4w]™ ([url=http://www.myskinrecipes.com/shop/%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%89%E0%B8%B2%E0%B8%99%E0%B8%A3%E0%B8%B4%E0%B9%89%E0%B8%A7%E0%B8%A2%E0%B8%AD%E0%B8%A2/74-vitamin-b3-niacinamide-%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%9A%E0%B8%B53.html:6rkvva4w]Vitamin B3, Niacinamide[/url:6rkvva4w]) 5%
Viola Odorata ([url=http://www.myskinrecipes.com/shop/%E0%B8%94%E0%B8%AD%E0%B8%81%E0%B9%84%E0%B8%A1%E0%B9%89/2954-violet-leaf.html:6rkvva4w]Violet Leaf[/url:6rkvva4w]) Extract สารสกัดสวีทไวโอเล็ต 2%

If the formula already contains 2% [url=https://www.myskinrecipes.com/shop/%E0%B8%A5%E0%B8%94%E0%B8%81%E0%B8%B2%E0%B8%A3%E0%B8%AD%E0%B8%B1%E0%B8%81%E0%B9%80%E0%B8%AA%E0%B8%9A%E0%B8%82%E0%B8%AD%E0%B8%87%E0%B8%AA%E0%B8%B4%E0%B8%A7/7387-succinic-acid.html:6rkvva4w]Pure-Succinic™[/url:6rkvva4w], is it necessary to add 1% [url=http://www.myskinrecipes.com/shop/34-%E0%B8%AA%E0%B8%B2%E0%B8%81%E0%B8%B1%E0%B8%99%E0%B9%80%E0%B8%AA%E0%B8%B5%E0%B8%A2:6rkvva4w]preservative[/url:6rkvva4w] [url=http://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B8%B2%E0%B8%81%E0%B8%B1%E0%B8%99%E0%B9%80%E0%B8%AA%E0%B8%B5%E0%B8%A2/1001-ethylhexylglycerin-caprylyl-glycol.html:6rkvva4w]Mild Preserved Eco[/url:6rkvva4w] as well? Also, based on the ingredient combination, is the formula compatible, or are there any adjustments needed?

MySkinRecipes Expert · Accepted Answer

Essence Formulation Review

Let's review your Essence formulation and address your questions regarding preservation and compatibility.

Preservation

You asked if adding 1% Mild Preserved Eco™ is necessary since your formula already contains 2% Pure-Succinic™.

Pure-Succinic™ at 2% is recommended for its antimicrobial properties, particularly against P.Acnes, and can act as a preservative. However, its broad-spectrum efficacy against all types of bacteria, yeast, and mold might not be sufficient on its own for a complex water-based formula containing multiple botanical extracts and humectants.
Mild Preserved Eco™ (a blend of Ethylhexylglycerin and Propanediol) is commonly used to provide broad-spectrum preservation and can boost the effectiveness of other antimicrobial agents. It is effective over a wide pH range (4-9).

Given the composition of your essence, which includes several ingredients that can support microbial growth, adding 1% Mild Preserved Eco™ is highly recommended to ensure robust and broad-spectrum preservation. Relying solely on Pure-Succinic™ might leave the formula vulnerable to contamination.

Compatibility and Adjustments

Your formula contains a powerful combination of active ingredients targeting various skin concerns. However, there are a few potential compatibility issues and points to consider:

Salicylic Acid Solubility: The Salicylic Acid (BHA) powder you listed is not water-soluble. At 2%, it will not fully dissolve in your water/glycerin base, leading to potential precipitation or a cloudy appearance. To properly incorporate 2% Salicylic Acid, you should either:
- Dissolve the Salicylic Acid powder in a suitable solvent (like Isopentyldiol, Propylene Glycol, or Butylene Glycol) before adding it to the water phase.
- Use a water-soluble form of Salicylic Acid (e.g., Complex Salicylic Acid powder, Liquid Salicylic Acid, or SalicSoft™).
pH Balance: The formula contains several ingredients that influence pH and have specific pH requirements for optimal stability and efficacy:
- Salicylic Acid and Pure-Succinic™ are acidic.
- Madecassoside and Yeast Radiance™ require a pH between 4.0-6.5.
- Safe-B3™ (Niacinamide) is most stable and effective between pH 4.0-7.0.
- ActiveProtec™ OX requires a pH above 4.
Salicylic Acid is typically most effective at a lower pH (around 3-4), but this range conflicts with the stability and efficacy requirements of Niacinamide, Madecassoside, Yeast Radiance™, and ActiveProtec™ OX, and could increase the risk of Niacin formation from Niacinamide (though Safe-B3™ is high purity). Aiming for a final formula pH between 4.5-5.5 is a common compromise in such complex formulations. This range supports the stability of most ingredients, minimizes irritation, and is suitable for skin, although Salicylic Acid's exfoliation efficacy will be reduced compared to a lower pH.
Viscosity/Texture: Ingredients like 4MSK and ActiveProtec™ OX are electrolytes. Electrolytes can interfere with the gelling or thickening properties of polymers like Hyaluronic Acid, Double Hyaluron Liquid, and Snow Mushroom Hyaluron. The presence of these electrolytes might result in a thinner texture than you might expect from the humectant concentrations.
Mixing Order: Pay close attention to the mixing instructions for individual ingredients. Madecassoside and Yeast Radiance™ should be added in the final step and should not be exposed to heat. If using Salicylic Acid powder, dissolve it in a solvent first before combining with the water phase. Add Disodium EDTA early in the water phase.

Recommended Adjustments Summary:

Preservation: Add 1-1.5% Mild Preserved Eco™ for enhanced broad-spectrum preservation.
Salicylic Acid: Use a water-soluble form or pre-dissolve the powder in a suitable solvent.
pH Adjustment: Carefully adjust the final pH to the 4.5-5.5 range using a suitable acid or base, and consider using a buffer for stability.
Texture: Be aware that the texture may be thin due to electrolytes.
Mixing: Follow specific ingredient instructions regarding heat and addition phase.

By making these adjustments, you can improve the stability, efficacy, and safety of your Essence formulation.