Home Cosmetic Science Talk Formulating Cosmetic Industry Challenge Testing Hydrosols

  • Challenge Testing Hydrosols

    Posted by mikethair on October 18, 2016 at 6:27 am

    We purchase a hydrosol in bulk (5L) and repackage into 100 mL. The supplier assures us that preserving is not required. To-date no issues with our Challenge Test Reports on these products, but one report has just come in with the following results:

    The sample showed a log reduction of >5 and no increase from the 14 days count against Staphylococcus aureus at 28 days.
    Escherichia coli and Pseudomonas aeruginosa showed a log reduction of >1 and >2 and no increase from the 14 days count at 28 days.
    One(1) type of yeast and one(1) type of mould showed a log reduction of 0.04 and
    -0.31 respectively which are increase from the initial count at 14 days at 28 days.

    The product did not meet the criteria specified under product category 2 under USP 51 Antimicrobial Effectiveness Testing due to the increase from the initial count at 14 days for yeast and mould.

    This raises the question then, for us to be more certain, what would be an appropriate preservative for this type of product for us to add when we repackage in our production facility?

    Thanks

    belassi replied 7 years, 6 months ago 4 Members · 4 Replies
  • 4 Replies
  • johnb

    Member
    October 18, 2016 at 8:31 am

    As you have assurances that a presevrative is not required, you should approach your supplier with your concerns - with the evidence you have and see what their response is!

  • mikethair

    Member
    October 18, 2016 at 9:59 pm

    Thanks @johnb …..yes, I have approached the supplier and response as follows:

    “This organic Rose Otto Hydrosol Batch 1005653  was manufactured in June 2014.  We received the stock from our supplier in April 2015.
     
    That’s means by the time customer send sample to test in August 2016, sample has already been 2 years old . The failed challenge test results is not surprised but not too bad, small growth of microorganisms from 0 day to 14 days, no change after 28 days.
     
    We also attach supplier’s COA of the same batch, which shows Microbiological tests”

    Not all that satisfactory in my opinion, as according to labelling from the supplier, we have not yet exceeded the use-by-date.

    Which brings us back to the original question…..what would be an appropriate preservative for this type of product for us to add when we repackage in our production facility?

  • Microformulation

    Member
    October 19, 2016 at 1:09 am

    Potassium Sorbate, Sodium benzoate. Ph adjusted to 4-6. Good cGMP. Proper stockkeeping. First in and first out. Don’t stock more than you can utilize within a realistic period of time.

  • belassi

    Member
    October 19, 2016 at 1:18 am

    Don’t stock more than you can utilize within a realistic period of time
    Absolutely. I keep each batch in Excel with its date and lot number and any production notes. So, I can search on a particular product number, divide the total by the date range (how many months) and say to myself, “is it worth continuing to produce this product considering that we only produced (sold) xx units per month”.

Log in to reply.