Hi everyone, I want to ask about preservative selection. I was taught to always use a broad spectrum preservative in the highest recommendation rate of the supplier to get the best shelf life of the product. However with the hundreds of different preservative blends out there, how do we decide the best one?
Since I emphasize on broad spectrum, I always use combination of DMDM hydantoin 0.6% (maximum limit, and for bactericidal function) and Potassium sorbate 0.6% (for fungicidal function). Both of these comes from singular item (not a blend). I choose this because i think it is easy to work with, as it can stand heat to 80C, and potassium sorbate work effectively in pH <6.
I can see many bodywash, shampoo and wash-off product use these preservative, so I suppose it is fine in these range. But what about leave-on product?
I do not see many lotion, creams, and moisturizer use these preservatives. What I have gathered, many uses like Euxyl PE9010 (phenoxyethanol & ethylhexylglycerin), or opthiphen (phenoxyethanol, sorbic acid, caprylyl glycol). Are these milder or specially made for leave-on product?
Otherwise, what do you think of using DMDM Hydantoin and Potassium sorbate for cream, or lotion? (even for face cream). It is very cheap and accesible, but I'm worried about its safety for leave-on.
Thanks and really looking forward to hear your experience guys