Liquid Soap Formulation and Thickener Substitution (NaCl vs Sugar Thick)

Okay, I can help you review this liquid soap formula and your questions about substituting the thickener.

Here is the analysis of your formula and answers to your questions:

Formula Review:
Your formula uses a combination of mild surfactants (Disodium Laureth Sulfosuccinate, Cocamidopropyl Hydroxysultaine, Cocamidopropyl Betaine) which is good for creating a gentle liquid soap. It also includes humectants (Glycerin, Propanediol), a chelating agent (EDTA), a solubilizer/emulsifier (PEG-80 Sorbitan Laurate, PEG-40 Hydrogenated Castor Oil), a conditioning agent (Shea Butter Water Soluble), color, fragrance, a preservative (Phenoxyethanol), and a thickener (PEG-120 Methyl Glucose Dioleate).

The formula structure and ingredient types are suitable for a standard liquid soap. Whether you need further adjustments depends on the specific properties you desire (e.g., desired viscosity, foam level, clarity, skin feel). You might need to fine-tune the percentages of surfactants or thickeners based on small-scale trials to achieve your preferred result.

Substituting Sugar Thick (PEG-120 Methyl Glucose Dioleate) with NaCl:

• Can NaCl replace Sugar Thick? Yes, Sodium Chloride (NaCl) can be used as a thickener in surfactant systems like yours, especially since you have ionic and amphoteric surfactants.
• What percentage of NaCl is needed? This is difficult to give an exact percentage for several reasons:
  • NaCl thickens surfactant systems differently than PEG-120 Methyl Glucose Dioleate.
  • The required amount of NaCl for thickening is highly dependent on the specific types and concentrations of all the surfactants in your formula.
  • NaCl thickening follows a "salt curve" - adding more salt increases viscosity up to a point, after which adding more salt will decrease viscosity.
  • PEG-120 Methyl Glucose Dioleate often provides a more stable viscosity build and can be less sensitive to temperature changes or other formula components compared to NaCl.

Recommendation for using NaCl:

If you choose to use NaCl instead of PEG-120 Methyl Glucose Dioleate, you must add it gradually while stirring and monitoring the viscosity. There is no fixed percentage that will directly replace 3% of PEG-120 Methyl Glucose Dioleate.

• Start by preparing your base formula without the thickener.
• Dissolve a small amount of NaCl (e.g., 0.5% to 1% of the total formula weight) in a little water.
• Slowly add the NaCl solution to your soap base while stirring gently.
• Continue adding the NaCl solution in small increments, stirring well after each addition, until you reach the desired viscosity. Be careful not to add too much, or the viscosity might decrease.

You will need to determine the optimal percentage through experimentation with your specific batch.