Making Mouthwash

Preservatives for Mouthwash

For mouthwash formulations, which are water-based and intended for oral use, selecting an appropriate preservative is crucial to prevent microbial growth. Based on the available information, several broad-spectrum, water-soluble preservatives are suitable:

• Global Guard™ 221: This is a water-soluble, broad-spectrum preservative effective in a pH range of 2-7. It is globally approved and used at a rate of 0.5-1.1%.
• Mild Preserved™ COS: Another water-soluble, broad-spectrum preservative that works in a wide pH range of 2-8 and is odorless. It is used at a rate of 0.75-1.5%.
• Preserve-BSB™: This preservative is a blend of benzyl alcohol, sodium benzoate, and potassium sorbate, soluble in water. It is effective up to pH 5.5 and used at 0.3-1.0%.
• NaturePreserve™ Ultra: A natural preservative (Gluconolactone & Sodium Benzoate) that is water-soluble and works in a pH range of 3-6. It is used at 0.75-2.0%. Note that its powder form might require careful dissolution, and the pH needs to be within its effective range.

When choosing a preservative, consider the final pH of your mouthwash formula and the desired usage rate. Always perform challenge testing to confirm the preservative's effectiveness in your specific formulation.

Addressing Cloudiness with PEG-20

Cloudiness when mixing PEG-20 with water, especially when incorporating oils or fragrances, typically indicates that the PEG-20 is not effectively solubilizing the oily components in the water phase. PEG-20 is a type of solubilizer, but its capacity can be limited depending on the type and amount of oil/fragrance used.

To achieve a clear solution, you may need to use a more powerful solubilizing agent or increase the concentration of the solubilizer. Consider these options:

• Flora Solve™ Clear: This is a fragrance solubilizer designed to combine essential oils and fragrance oils with water without needing alcohol. It is clear, colorless, and odorless and is effective at creating clear solutions. The recommended usage is mixing 2-5 parts Flora Solve™ Clear with 1 part perfume/oil before adding this mixture to the water phase.
• Ultra Solve™: A highly effective solubilizer capable of dissolving various oils, including essential oils and fragrances, in water. It can hold more oil than many other solubilizers.
• Eco Solve™: Similar in performance to Ultra Solve™ but often more cost-effective. It also effectively dissolves oils, perfumes, and essential oils in water, providing clarity.

When using these solubilizers, it is crucial to mix the solubilizer thoroughly with the oil/fragrance first until clear before gradually adding this mixture to the water phase while stirring. Adding water directly to the solubilizer-oil mix can cause it to gel or turn cloudy.

Alcohol Content in Mouthwash

Alcohol is traditionally used in some mouthwash formulas for its antiseptic properties and to help dissolve certain ingredients, including flavor oils. However, mouthwashes can also be formulated effectively without alcohol.

There is no single "maximum" alcohol percentage for all mouthwashes; it varies widely depending on the product type, intended use, and target market. Traditional antiseptic mouthwashes might contain alcohol concentrations ranging from 10% to over 20%. However, many modern and milder mouthwashes are formulated with lower alcohol content or are completely alcohol-free to reduce potential irritation, dryness, or burning sensations in the mouth.

If you aim for a milder or alcohol-free formula, you would rely on other antiseptic agents (if desired) and use effective solubilizers like those mentioned above to incorporate flavorings.