Formulate a watermelon and almond cleansing foam

This is where I purchased my key ingredients:

Watermelon hydrosol – INCI: Citrullus Vulgaris (Watermelon) Fruit Water

Resplanta Phyto-6 Almond MB – INCI: Sweet Almond Oil Polyglyceryl-6 Esters, Aqua

Making skincare doesn’t have to be complicated to be meaningful. This foaming cleanser is simple, effective, and full of care, just like a good gift should be. This gentle cleanser is a small but meaningful way to show care, perfect as a gift for someone special or as a daily reminder to look after your own skin with kindness.

Method:

• Weigh Phase A in a clean beaker. Stir well.

• Add Phase B to A and stir. You can use a magnetic stirrer if you have one.  It may take a while to fully disperse the water-soluble almond oil. 

• Add Phase C, stirring slowly to avoid foam. 

• Add Phase D.

• Check and adjust the pH if needed to 4.5-5.5.

  * You need to have a foamer bottle for this formula.

  ** I used a drop of soap colouring to achieve this colour (cranberry). While I love natural colourants, in a formula like this, you are better off with soap colourants to achieve good stability. This is, of course, optional.

  Add a handwritten label or note if you’re gifting it. Want to go the extra mile? Pair it with a fruity or floral face mist or a handmade cloth for a thoughtful, complete set.

This formula covers more ground than it looks like at first glance. Here’s what you’re practising when you make it:

Working with surfactants at low concentrations: Foaming cleansers don’t need high surfactant levels to work well. Learning to balance foam quality and mildness at lower percentages is a skill that transfers to shampoos, body washes, and other cleansing products.

Incorporating water-soluble oils: Resplanta Phyto-6 Almond MB behaves differently from a traditional oil. Understanding how water-dispersible ingredients work in aqueous systems opens up a whole range of formulation possibilities beyond emulsions.

pH adjustment for skin and preservation: Getting the pH right matters for two reasons here: skin compatibility and preservative efficacy. Practising pH adjustment in a simple formula like this builds the habit before you tackle more complex systems.

Choosing and using a preservative system: Every water-containing formula needs preservation. This project gives you a straightforward context to practise selecting a preservative and confirming it’s within its effective pH range.

Understanding ingredient functions: With a short ingredient list, you can focus on understanding what each component actually does rather than just adding things because a recipe told you to.

Once you’ve made the base version and you’re happy with it, have a play with some swaps:

Watermelon hydrosol → cucumber hydrosol or rose water: Both work well in cleansers. Cucumber is light and cooling, whilst rose water adds a more classic, floral character. Either gives a similarly gentle scent without overpowering the formula.

Resplanta Phyto-6 Almond MB → Resplanta Phyto-6 Avocado or another water-dispersible oil: There are PEG-free water-soluble oil blends from several suppliers. If you don’t want to use them or can't source them, you can also omit the water-soluble oil entirely and increase the water to make the formula 100% aqueous.

Rice protein → hydrolysed oat or quinoa protein: These offer similar barrier support and skin feel. Oat protein is widely available and generally well tolerated.

Sodium PCA → glycerin or sodium lactate: Both are effective humectants. Glycerin is the most accessible option and works well at 2%.

Niacinamide: You can omit this entirely if needed. It’s a bonus in this formula, not essential to the product’s function.

The broader principle here is that once you understand the formula's structure, you can adapt the individual ingredients to suit your preferences, skin type, or what you have available. A patch test is always a good idea when working with new swaps.

SAFETY NOTE

This formula is designed for personal use as a rinse-off facial cleanser. It’s not intended for use around the eyes and should be rinsed off thoroughly after use.

If you’re using essential oils or fragrance oils (this formula doesn’t include any, but if you choose to add them), check the IFRA guidelines for maximum safe usage levels in rinse-off products and be aware of any known sensitisers.

Always perform a patch test before using a new formulation on your face, especially if you have sensitive or reactive skin. Apply a small amount to the inside of your wrist or behind your ear, leave for 24 hours, and check for any irritation.

When sourcing your ingredients, make sure you’re purchasing from reputable suppliers who provide proper documentation, including Certificates of Analysis (COAs) and Safety Data Sheets (SDS). If you’re using any fragrance materials, request the IFRA certificate.

This blog post is for educational purposes only and is not intended to replace cosmetic safety assessments required for commercial sales. If you plan to sell products, a formal safety assessment by a qualified assessor is a legal requirement in the UK and EU.