• Microbial Testing Kits

    Posted by RKB on May 17, 2018 at 9:01 pm

    I’m seeing kits to test for microbial contamination available at places like Lotion Crafter. Should people who are looking to start a cosmetic line be using things like this in lieu of lab testing? I was startled seeing people use them as I didn’t think they could equate to the more formal testing available.

    Dr Catherine Pratt replied 2 years, 5 months ago 12 Members · 19 Replies
  • 19 Replies
  • OldPerry

    Member
    May 17, 2018 at 9:21 pm

    Those tests are for people who are doing a hobby. I wouldn’t rely on them to provide evidence that your products are safe for sale to the public.

  • RKB

    Member
    May 17, 2018 at 9:31 pm

    Thank you, Perry!

  • mikethair

    Member
    May 20, 2018 at 10:27 am

    We use MIKROCOUNT DUO. We validate results with tests done by an external registered microbiol lab on a set basis, and all is good. You will need an incubator.

  • Dr Catherine Pratt

    Member
    May 22, 2018 at 9:25 am

    Starting a product at home might start out as a hobby, so why not give those that want to learn more an introduction to Microbiology. Then when ready to go to the big manufacturers have them tested in a proper lab. At least its a start!

  • mikethair

    Member
    May 26, 2018 at 5:54 am

    We use MIKROCOUNT DUO. We validate results with tests done by an external registered microbiol lab on a set basis, and all is good. You will need an incubator.

  • tanelise

    Member
    May 28, 2018 at 12:55 am
  • carvan

    Member
    June 1, 2018 at 5:09 am

    not sure you need incubator if your willing to wait 30 days at room temp. I use Mikrocount slides to initially test preservative systems and only send to lab if it passes the 30 day challenge. The lab test can get very expensive quickly especially if you have multiple products to test. What you want to avoid is having to get same product tested multiple times until it passes. The strips should eliminate that. good luck.

  • MarkBroussard

    Member
    June 4, 2018 at 9:50 pm

    If your preservative is not working, you should see some microbial growth on a test strip within 72 hours or so.  For a $400 investment, it is well worth it.

    I use Schuelke test strips and find that they are excellent predictors of a pass/fail on a PCT.  Look at it this way … if using microbial test strips saves you from only one failed PCT,  that savings covers the cost of your incubator.

  • RKB

    Member
    July 14, 2018 at 10:47 pm

    @MarkBroussard, can you recommend an incubator? Thank you!

  • GreenFrog

    Member
    July 15, 2018 at 1:26 pm

    those test kits in various forms of complexity are also being marketed to companies as a cost savings to small businesses.  

  • Microformulation

    Member
    July 15, 2018 at 2:30 pm
    @GreenFrog Yes, but the final definitive testing still must be sent off. They are best used as an internal screening tool to minimize outside testing costs.
  • anhydrousbilly

    Member
    October 16, 2020 at 3:47 am

    What if your product is anhydrous, below .6 water activity?

  • suswang8

    Member
    December 7, 2021 at 5:48 pm

    Can someone recommend a place to buy these Schuelke Mikrocount kits?  Thank you.

  • PhilGeis

    Member
    December 7, 2021 at 6:07 pm

    I’d not count on dip slides beyind water testing for anything beyond hygiene monitoring, hobby and presumptive testing. 

  • mikethair

    Member
    December 7, 2021 at 10:12 pm

    PhilGeis said:

    I’d not count on dip slides beyind water testing for anything beyond hygiene monitoring, hobby and presumptive testing. 

    We have used Schuelke Mikrocount in our GMP Certified production facility for years. But they need to be used intelligently.
    PET/Challenge Tests are done in an external, certified lab. Regularly, the Schuelke Mikrocount results are validated with samples being sent to an external certified lab.
    Over the five years we have used Schuelke Mikrocount they have not let us down. But again, this outside validation of results is an important part of our regime.
  • suswang8

    Member
    December 8, 2021 at 5:30 am

    Let me please rephrase, then:  Are there any microbiology test kits that someone can recommend for amateur use prior to getting professional tests done?  (To be clear:  I realize the “at home” testing would not be a substitute for professional testing.)

  • MarkBroussard

    Member
    December 8, 2021 at 6:07 pm

    @suswang8:

    @mikethair answered your question:

    We have used Schuelke Mikrocount in our GMP Certified production facility for years. But they need to be used intelligently.
    PET/Challenge Tests are done in an external, certified lab. Regularly, the Schuelke Mikrocount results are validated with samples being sent to an external certified lab.
    Over the five years we have used Schuelke Mikrocount they have not let us down. But again, this outside validation of results is an important part of our regime.
  • PhilGeis

    Member
    December 9, 2021 at 12:15 pm

    At risk of pedantry - the dip slide such as Schuelke’s is not “validated” by external labs showing the same result.  If it were - you wouldn’t need the external lab asnd it is clearly not.
    The industry standard test (that would meet FDA expectations) includes growth promotion and neutralization controls for every product and internal lab controls maing is costly e.g.  -https://www.uspnf.com/sites/default/files/usp_pdf/EN/USPNF/generalChapter61.pdf

    Pretty sure a company reporting contamination of one product  would find the FDA unsatisfied that dip slide was adequate for addressing micro quality of any product. 

    Dip slides might give you a heads up but shouldn’t replace accepted testing.  If you can’t afford quality, perhaps don;t sell/distribute your product

  • Dr Catherine Pratt

    Member
    December 9, 2021 at 2:13 pm
    Hi there,
    You can buy the home microbial test kit at Lotioncrafter Or New Directions to do a check before sending your sample off to the PC2 lab facility.
    It will give you an indication of microbial count or cfu’s. The STD deviation will be a lot greater but I guess its ok to see if its a pass or fail!
    Enjoy. Let us know how you go??
    Best Catherine

Log in to reply.