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  • PhilGeis

    Member
    November 25, 2020 at 10:59 pm in reply to: What preservatives do you use most often?

    I use 9010 + Phenyl Ethyl Alcohol.
    I don’t recall 9010 having an odor.  Maybe you got a bad batch?
    In any case… PE Alcohol has a lovely rose fragrance…so it might cover the odor you are having with the 9010.

    It blends well with about any floral scent, and especially well with rose absolute.  :)  

    Why phenyl ethyl alcohol?  It targets that same bugsas phenoxyethyl  only less effetively and you still have a fungal gap. 

  • PhilGeis

    Member
    November 25, 2020 at 2:22 pm in reply to: Preservative for pH 9-10 liquid soap

    I’m sure no packaging expert - but Clorox bleach (e.g. pH 12) -  think it’s in HDPE.  http://menda.descoindustries.com/PDF/ChemicalResistanceChart.pdf
    Are you sure the anti-wrinkle is safe - esp. if used near eyes?

  • PhilGeis

    Member
    November 25, 2020 at 12:12 pm in reply to: preservative potassium nitrate

    KNO3 is in toothpaste as a desensitizing agent , not preservative.

  • PhilGeis

    Member
    November 25, 2020 at 10:17 am in reply to: Preservative for pH 9-10 liquid soap

    Let me also add -  as the pH becomes extreme, the classic PET becomes less useful - the product “passes” with or without preservaton even tho suscpetible to contamination.  Be aware -the USP bugs are lab creatures that happily grow at ~ neutral pH where they’d lived since initial submission to ATCC up to 80+ years from isolation - on neutral pH media.
    Also - the product contaminants as pH’s become extreme start to engage with extremophiles that won’t grow well (potentially won’t grow at all) on conventional media but will still deteriorate the product.  Those bugs contaminating at extreme pH are less likely to be pathogenic but preservation at those pH’s is a real pain.

  • PhilGeis

    Member
    November 25, 2020 at 8:30 am in reply to: Preservative for pH 9-10 liquid soap

    Leo said:

    @PhilGeis Sir-the packaging for the liquid soap (pH 10) is a plastic container with a foam pump.

    Is a micro challenge recommended and definitive?

    Which preservative(s) would you use?

    In your experience, regarding a different product, have you heard of microbes contaminating a gel at pH 11?

    Not sure I’d preserve that soap.  Is this a cosmetic?  How effective do you see the package as protection?  Perhaps do some in-use exppsure.

    ph !1 gel.  Can you tell me smething about the product?  At that pH - is it a cleanng product?

  • PhilGeis

    Member
    November 24, 2020 at 9:34 pm in reply to: What preservatives do you use most often?

    Paprik - if you can tke the smell, with 9010 - mayte some Benzoate if the pH workand EDTA.  What’s the product

  • PhilGeis

    Member
    November 24, 2020 at 6:40 pm in reply to: Fungicidal Preservative

    Saligard EHGP would be pretty ineffective vs fungi.

  • PhilGeis

    Member
    November 24, 2020 at 6:04 pm in reply to: Welcome to the forum

    I’m Phil Geis.  Was responsible for micro P&G’s cosmetic and lother businesses for ~ 2 decades. Retited to consuultant.  I’ve followed Perry’s info - been a fan for years. Want to share my knowledge and experience and learn from  you guys.

  • PhilGeis

    Member
    November 24, 2020 at 3:18 pm in reply to: Preservative for pH 9-10 liquid soap

    mikethair said:

    If the liquid soap has a pH 9 - 10, a preservative is unnecessary. Refer to ISO

    29621 “Cosmetics — Microbiology — Guidelines for the risk assessment and identification of microbiologically low-risk products.”
    We have a GMP Certified production facility producing a lot of liquid soap, and export globally. These products are Notified with cosmetics authorities and all the necessary testing is done in our in-house labs and verified by external labs.

    Liquid soaps can be contaminated.   I’ve observed actual colonies of bacteria in/on amended bar soaps.  
    ISO 29621 claims pH >10 as cutoff for preservation, not 9-10.  Recall please ISO’s are concensus decisions - good as a guideline but not absolute.  Certainly one can have microbial contamination at >10.  

    Please also recall that preservation is primary intended to protect the product in-use, not as delivered.  In this, packaging is an important preservative element - maybe the most important for some products.

    Have you in-use data for your application?

  • PhilGeis

    Member
    November 24, 2020 at 3:12 pm in reply to: Preservative for pH 9-10 liquid soap

    ketchito said:

    @Leo Organic acids like Benzoic or Sorbic acid work well for this purpose (you can get them as their salts: Sodium benzoate or Potassium sorbate). You can start at 0.3%. 

    But if you don’t mind using a formaldehyde donor, then Glydant Plus or Liquid Germal Plus are very good broad spectrum preservatives. You can find a lot of literature about them. 

    Organic acids would be useless in alkaline products, including liquid soap.

  • PhilGeis

    Member
    November 24, 2020 at 3:00 pm in reply to: preservative potassium nitrate

    As Perry said, look to those professional entities like CIR and SCCS who detail information and live with their decision.  You can alsways find a researcher publishing an affimative opinion of disaster based usually on irrelevant and or bad science.   

    On the credibility side - SCCS just published this opinion of Propyl parabens.  Please note the depth of its consideration.   ” SCCS has concluded that propylparaben is safe when used as a preservative in cosmetic products up to a maximum concentration of 0.14 %.” https://ec.europa.eu/health/sites/health/files/scientific_committees/consumer_safety/docs/sccs_o_243.pdf?fbclid=IwAR0p-PkyKeHFEcUyorfxdteQXrJru35M_f5GhXgAO2iy096yIVavgmggcVo

  • PhilGeis

    Member
    November 24, 2020 at 2:17 pm in reply to: What preservatives do you use most often?

    Paprik said:

    I’m really struggling with getting a nice preservative. 
    I’ve started with Liquid Germall Plus, but I’m afraid some of my customers won’t and don’t like the fact, that it’s formaldehyde donor. 
    So was looking for something different. I found Euxyl PE 9010. I like it, but the smell is just nah. A new one I tried was Geogard Ultra TM (Gluconolactone (and) Sodium Benzoate (and) Calcium Gluconate), it’s a powder, seems to be super nice and easy to use, but it messes up with my pH. So I tried Microcare DB, seems also nice, it’s EcoCert, BUT the smell! So it’s hard to find one without any smell, “scary” names like Parabens or Formaldehyde and won’t mess up with my products. 

    But as for me, I’m using Liquid Germall Plus the most. 
    Also thinking about Naticide - but I know there’s a smell to it. And it’s expensive. 

    What do you think about Potassium Sorbate & Sodium Benzoate? 

    Certainly a wide range of anticipated levels of efficacy in your suggestions - mostly on the poor side.   Not knowing the product category -I’ll offer that you should assemble a combination of  preservatives (with a chelator like EDTA)  that SHOULD work and confirm with PET.  None of the sytems you desceibed are likely to be as effective as Germall Plus esp. vs Gram negative bacteria.  Organic acids require an appropriately acidic pH and are weak preservatives, esp re. Gram negative bacteria.  Natacide is a combination of unidentified (unknown?) “natural” materials.  Even if effective - you’re offered no assurance that batch to batch compostions will be identical to that you qualified. 
    Why not use phenoxyethanol in combination?

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