Cosmetics Formulation Development

Hello, I would like to ask, how to use Xanthan Gum In the current gel making ingredients use Xanthan Gum 2% and use sodium benzoate 0.05% and Potassium Sorbate 0.05% to สารกันเสีย After mixing it for 1 month, bacteria or fungi (black) appear on the gel surface. Ask >> the body Xanthan Gum should be used with สารกันเสีย which one?? to get the best performance or the longest service life. (No black fungus) The gel made from this product is a gel that must be able to enter the mouth (edible) as well. Please advise. Thank you.

Hello สารกันเสีย is not enough, use Mild Preserved Eco 2% + Global Guard™ 1.5% and mixing step Heat should be used to disinfect if possible