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  • Emulsification and Homogenization questions

    Posted by stephanm on September 13, 2017 at 10:52 pm

    Hi - I realize there are a few threads about this already, but they all seemed to be concerned with keeping an unrealistically low budget. I’ll probably have several follow-up questions, so here is the first batch!


    We manufacture and sell (to consumers and B2B) organic body wash (a gel-like body wash as is typical), and a foaming applicator compatible hand & body wash (which as you know has a consistency closer to water).

    The business has taken off. Our commercial division supplies businesses across a variety of sectors (typically they fill their own soap dispensers, gel or foaming format, or purchase our smaller portable foaming pump 500ml bottles), and our consumer division sells directly to customers online, and B2B to retail locations in wholesale amounts.

    So - really there are 2 formulas that it boils down to: gel and foaming formulas. But they’re essentially identical except for thickening.


    We’re scaling. Our amateur start-up equipment won’t do the trick for long.

    We have some problems with our foaming soap - separation occurs quite quickly. With the gel soaps, it happens much more slowly, but it happens eventually. Much less of a concern though.

    The water-like foaming version, though.. because of the texture, it is much less forgiving of our inferior process. Stuff floats to the top. We have a silly process where we ‘only use’ the bottom 95% of a batch after a period of settling. The gel soaps don’t suffer from this problem because of the thickness. Well, it takes a long long time at least, and isn’t even noticeable.

    Company image:

    All-natural. Yes, we’re one of those companies that will NOT introduce an ingredient that sounds scary. So, not so much looking for any changes that would involve changing ingredients across 7 SKUs and all of the re-labeling that that would involve.

    Because of this image, customers are actually very forgiving with any imperfections in the product. In fact, just like all-natural peanut butter, they see the imperfections as VALIDATION that we are, in fact, an all-natural superior formulation without additives.


    1) For a company looking to seriously improve the EMULSIFICATION and HOMOGENIZATION of its 2 products, what would be the natural entry-level step in terms of equipment? I’ve seen so, so many recommendations. A lot of you have pointed to the Lee Trimix High Shear Mixer. Boy it does look nice. But is it overkill as we scale from home-to-small-facility for the first time? We’re not against spending a thousand or two on an intermediate Chinese machine.

    2) Before we acquire such machinery, the only thing at our disposal is a Waring Big Stix immersion blender. We use this primarily during tracing/saponification. Is it possible, in the meantime, to use this machine for product emulsification / homogenization (and reducing particle size)? Can we possibly use this as a poor man’s version for the time being? I figured that the blender head made it inappropriate for such an application.

    3) Definition question: I understand that ’emulsification’ means to mix ingredients (and keep them that way) that are normally un-mixable (water and oil, for example), and that ‘homogenization’ means to make the product have a very uniform texture (and perhaps reduce particle size), but they often seem to *come together* in equipment: does a homogenizing machine ALWAYS, as a consequence, also act as an emulsifier? I almost treat these 2 things as the same process in my head, although logically I understand that they have separate definitions.

    4) What is the positive consequence of reducing the particle size of our product? Would it have any effect on how smoothly our product goes through a foaming dispenser (the foaming compatible formulation), for example?

    Thank you!!

    stephanm replied 6 years, 9 months ago 2 Members · 6 Replies
  • 6 Replies
  • Bobzchemist

    September 14, 2017 at 3:54 pm
    Let me try to answer your questions.

    1) Entry-level step in terms of equipment for a small-scale manufacturer. You need something that is more an emulsifier than a homogenizer, but the terms are frequently used interchangeably. Something with strong pumping action, which tends to eliminate silverson-type mixers. Either an Admix or an Arde-Barenco/Gifford-Wood type will do well for you.



    (If it were up to me, I’d grab the Admix ASAP)

    2) Can we possibly use this as a poor man’s version for the time being? Yes, but you may get results that will be hard to duplicate/scale-up without spending a lot.

    3) All homogenizers emulsify, not all emulsifiers are capable of generating enough shear force to homogenize.
    4) A - What is the positive consequence of reducing the particle size of our product? Improves stability, uniformity.
    B - Would it have any effect on how smoothly our product goes through a foaming dispenser (the foaming compatible formulation), for example? No.
  • stephanm

    September 14, 2017 at 7:20 pm


    I figured you’d be the first to respond! You have pretty much guided us through getting this far since our start in early 2016!! =) We refer to you as “that expert chemist on that website”..

    Thank you, some follow up questions I have (building upon what you have told me).

    First, additional info on our current equipment

    We trace/mix in this 13 Gallon double boiler tank (which I understand is quite popular for start-ups): http://www.soapequipment.com/Tanks/13GallonOilTank.htm

    No doubt we’ll need to up-size next year.

    Questions 2

    1) With the size of our tank in mind, would either of your 2 recommended emulsifying mixers be *too big* for us? The “Admix” looks great for emulsifying, but seems to be quite large/long. It seems to be something you’d “bolt” onto a big boiler.

    2) Let’s say we got a piece of equipment as you specified above. For how long (in seconds, minutes, etc.) would one typically run the machine at for products like ours? I understand that this isn’t a “one answer fits all” type of question..

    3) If, until we get such equipment, we use our handy Waring Bix Stix immersion blender as a poor man’s replacement for an emulsifier/homogenizer. How would we use this? Our guess: place the machine dead center of the double boiler, make sure we have enough product so that the ‘vortex’ does NOT bottom out (thus introducing air), and use on maximum speed. The suction is so powerful that we basically can’t move the blender up-and-down - which I believe we wouldn’t want to do anyway. And how long might we want to run this machine for?

    4) The emulsification/homogenization step - just to be very clear - is meant to be done after 100% of the ingredients have been mixed in, correct? All essential oils, jojoba, aloe vera, you name it.

    Thank you!

    (As a side effect of asking very newbie-level questions, I hope this thread becomes useful to others down the road.)

  • Bobzchemist

    September 14, 2017 at 7:31 pm

    Yes, it’s bigger than you need now - but if you can build a stand for it, and get a speed controller, you will have a mixer that will grow with your operation for about 1/10 of the cost for a new one. Check with Admix directly for the costs of new mixers. Alternatively, buy the used Admix, set it aside, and continue to use the Waring mixer until it pays to buy a bigger kettle. 

    Everything else should be determined experimentally.

  • stephanm

    September 14, 2017 at 7:42 pm



    I think one question I do need an answer to (I understand why most need to be determined experimentally) is how we might configure our Big Stix in the interim.

    Like - physically, how do we place it. Straight up, sitting on the bottom, dead center in the boiler?

    The homogenizing mixers that I see all seem to have a straight vertical configuration.

  • stephanm

    September 14, 2017 at 8:48 pm


    FYI, if ever you’d like some photos of the setup, I’m happy to post those. Thank you-

  • stephanm

    September 15, 2017 at 7:15 am


    These homogenizing mixers have such a different head structure than the Big Stix blender - which makes me wonder.. does there exist a “replacement head” for the Waring immersion blender that would turn it into something closer to a homogenizing mixer? Since it’s already a pretty powerful machine and all.

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