Additives for Natural Shampoo to Improve Hair Smoothness

Regarding the issue of hair roughness during rinsing when using shampoo made from oil and KOH, which is a normal characteristic of soap-based shampoos, adding ingredients that help coat the hair can make it smoother.

From the list of ingredients you have:

• Water lock (Polyquaternium-51): This ingredient is cationic, which has the property of adhering well to the hair shaft. It will help reduce roughness and make hair noticeably smoother during rinsing. This is the most direct solution for the problem you are experiencing.
• Pro Vitamin B5 (Panthenol) and Hydro Protein (e.g., Hydrolyzed Silk Protein, Hydrolyzed Pea Protein, Hair Wheat Protein): These ingredients are excellent conditioners for hair, helping to make it strong, moisturized, and softer once dry. However, they do not provide the same smooth feeling during rinsing as ingredients that directly coat the hair. Nevertheless, using them together can significantly improve overall hair health. You should also test the compatibility of some types of Hydro Protein (especially cationic types like Hair Wheat Protein) with your soap base.
• Coco wash (PEG-7 Glyceryl Cocoate) and Creamy foamer (Sodium Methyl Cocoyl Taurate): These two ingredients are primarily surfactants for cleansing and creating foam. They do not have the property of making hair smooth during rinsing directly.

Conclusion:

If you primarily want to solve the issue of hair roughness during rinsing, we recommend trying to add Water lock to your shampoo formula. Pro Vitamin B5 and Hydro Protein can be added to further nourish the hair for better health and softness after drying.