Proposed Gac Cream Formula (100g)

Water Phase:

• Water: 38.3 g
• Gac fruit extract: 25 g
• Disodium EDTA: 0.2 g
• Vitamin B3 (Safe-B3™): 5 g
• Pro Vitamin B5 (D-Panthenol Care): 3 g
• Natural Moisturizing Amino Acids: 5 g
• Xanthan Gum (clear gel type): 0.5 g

Oil Phase:

• Cetyl Alcohol: 6 g
• Glyceryl Stearate SE: 6 g

Cool Down Phase (add below 40°C):

• Azelaic Acid (Liquid Azelaic™): 10 g
• Phenoxyethanol (Extra Pure): 1 g

Instructions:

1. Combine all ingredients from the Water Phase in a heat-resistant beaker. Stir or blend until the Xanthan Gum is fully hydrated and the mixture is uniform. Heat this phase to approximately 70°C.
2. In a separate beaker, combine all ingredients from the Oil Phase. Heat this phase to approximately 70°C until the solids are completely melted and the mixture is clear.
3. Slowly pour the Oil Phase into the Water Phase while stirring continuously with a stick blender or whisk. Continue stirring until the mixture cools and a cream forms.
4. Once the cream has cooled to below 40°C, add the ingredients from the Cool Down Phase (Azelaic Acid and Phenoxyethanol). Stir until fully incorporated and the cream is smooth and uniform.

Ingredient Benefits:

• Gac fruit extract: (Based on your information) Provides natural components.
• Vitamin B3 (Safe-B3™): Helps reduce wrinkles, redness, and dark spots. It strengthens the skin barrier, improves hydration, and can help reduce oiliness, making it suitable for both dry and acne-prone skin.
• Pro Vitamin B5 (D-Panthenol Care): A great moisturizer that helps the skin retain water, improves elasticity, reduces inflammation, and aids in wound healing, beneficial for dry and irritated skin.
• Natural Moisturizing Amino Acids: Mimics the skin's natural moisturizing factors, providing excellent hydration and helping to keep the skin soft and supple. As discussed, this ingredient is not known to cause acne.
• Azelaic Acid (Liquid Azelaic™): Helps brighten skin, reduce dark spots, control oil production, and reduce acne. It is a versatile ingredient for combination and acne-prone skin.
• Cetyl Alcohol & Glyceryl Stearate SE: These work together to create the cream structure and provide a smooth feel. Glyceryl Stearate SE is a self-emulsifying base that helps bind the water and oil phases.
• Xanthan Gum: Acts as a thickener and stabilizer for the water phase, contributing to the overall texture of the cream.
• Phenoxyethanol: Acts as a preservative to prevent microbial growth and keep the product safe for use.
• Disodium EDTA: A chelating agent that helps improve the stability of the formula by neutralizing metal ions in the water.

Regarding your question about using coconut oil, as mentioned previously, coconut oil can be comedogenic for some people, especially those prone to acne. The proposed formula avoids added liquid oils to keep the texture light and minimize the risk of clogged pores. Cetyl Alcohol and Glyceryl Stearate SE provide some emolliency without being liquid oils.

Cream vs. Serum:

The difference between a cream and a serum is mainly related to their composition and texture.

• Serum: Typically has a higher concentration of active ingredients and is often water-based or has a very low oil content. Serums are usually lightweight, absorbed quickly, and designed to deliver specific active ingredients deep into the skin. They often have a thin, sometimes gel-like or watery consistency.
• Cream: Is an emulsion (a mixture of oil and water that are held together by an emulsifier). Creams have a higher oil content than serums, providing more hydration, emolliency, and helping to reinforce the skin's barrier function. They have a thicker, more substantial texture compared to serums. The general order of increasing oil content and thickness is Serum < Lotion < Cream < Ointment.

This formula should provide a moisturizing yet non-greasy feel, suitable for both your sister's dry skin and your combination/acne-prone skin.