Lotion Stickiness and Rancid Smell Issues

Hi, it's great that you achieved a good consistency and moisture level with your lotion! Let's address the rancid smell and stickiness issues.

Rancid Smell

This smell likely comes from the natural oils in your formula, as they can oxidize over time. While preservatives help prevent microbial growth, they don't stop oil rancidity. Adding a bit more fragrance (like your orange scent) might help mask it. Using oils that are less prone to oxidation or adding an antioxidant could also be considered in future formulations.

Stickiness

The stickiness on your hands is likely due to a combination of factors:

• The percentage of Vitamin E (Tocopheryl Acetate) is quite high at 2%. Vitamin E itself can feel a bit sticky, and it's usually used at lower concentrations (e.g., 0.1-1%).
• The natural oils you chose, Apricot Kernel Oil and Sweet Almond Oil, are described as having medium to slow absorption rates. Using a total of 6% of these oils, plus 2% Vitamin E, contributes significantly to the oily feel that lingers.
• While Glycerin at 10% is high, it typically contributes more to a slippery feel rather than stickiness. However, reducing it might still improve the overall skin feel.

To reduce stickiness, you could try:

• Lowering the Vitamin E percentage to 0.1-0.2% (it still provides antioxidant benefits at this level).
• Replacing some or all of the Apricot Kernel Oil and Sweet Almond Oil with emollients that absorb faster or feel less oily. Options include synthetic emollients or specific oils known for a lighter feel and better stability, such as Fractionated Coconut Oil, Mineral Oil (Paraffinum Liquidum), or Lipid Soft (Oil Free Emollient).
• Incorporating a light silicone like Dimethicone (Light, Low-Odor). Silicones provide a smooth, non-greasy feel and help the product spread easily.
• Reducing the Glycerin percentage to 3-5%.

Suggested Adjustments

Here is an example of an adjusted formula concept (percentages are illustrative and would need balancing):

• Water: q.s.
• Glycerin: max 5% (e.g., 3-5%)
• Oils/Emollients: total max 10% (e.g., a mix of a small amount of natural oil like Apricot Kernel Oil or Sweet Almond Oil (e.g., 2-3%) and a lighter emollient/oil like Fractionated Coconut Oil, Lipid Soft, or Mineral Oil (e.g., 7-8%))
• Vitamin E (Tocopheryl Acetate): 0.1-0.2%
• Dimethicone (Light, Low-Odor): Consider adding 5-10%
• Light Cream Maker: 1%
• Preservative: 1%
• Fragrance/Essential Oil: Adjust amount to mask scent.

These adjustments should help reduce the heavy, sticky feeling while maintaining moisture.