Home Cosmetic Science Talk Formulating Homogenization vs stirring

  • Homogenization vs stirring

    Posted by VitalikButerin on March 2, 2019 at 11:48 am

    hi 

    Many formulations instruct to Homogenize -
    1) what’s the difference? 
    2) Is it always needed to do one over the other? 
    3) formulas don’t state at what speed to homogenize, how will I know if I’m over doing it? 

    VitalikButerin replied 5 years, 7 months ago 3 Members · 5 Replies
  • 5 Replies
  • SkinNP

    Member
    March 6, 2019 at 3:16 am

    Not sure what you are making, but I’ll give what I have learned so far and let others chime in to correct the record if they see fit. Stirring doesn’t mean you have produced a homogeneous mixture, but if you have homogenized then you likely did so by stirring (maybe agitation is possible in other contexts as well). So, when they say homogenize, I think they’re saying disperse ingredients evenly (presumably by stirring). No skin off my back if someone wants to differ with me on this.

    Mixing equipment is really important. Bad equipment will frustrate you, and make your results hard to duplicate. Make sure the shaft is true, the range of speeds appropriate, and the propeller shape and size appropriate for what you are aiming to achieve. I try to get the propeller to about 2/3 the depth of the material. The mixing vessel should be at least 3 times the diameter of the propeller, have straight sides, flat bottom, and not react with your ingredients. Mix at a speed that doesn’t introduce a lot of air into the material, or cause foaming. In my experience, you need at least 20 minutes at a speed sufficient to produce a nice vortex (but not much faster).

    For what it’s worth. Good luck.

  • VitalikButerin

    Member
    March 6, 2019 at 10:46 am

    SkinNP said:

    Not sure what you are making, but I’ll give what I have learned so far and let others chime in to correct the record if they see fit. Stirring doesn’t mean you have produced a homogeneous mixture, but if you have homogenized then you likely did so by stirring (maybe agitation is possible in other contexts as well). So, when they say homogenize, I think they’re saying disperse ingredients evenly (presumably by stirring). No skin off my back if someone wants to differ with me on this.

    Mixing equipment is really important. Bad equipment will frustrate you, and make your results hard to duplicate. Make sure the shaft is true, the range of speeds appropriate, and the propeller shape and size appropriate for what you are aiming to achieve. I try to get the propeller to about 2/3 the depth of the material. The mixing vessel should be at least 3 times the diameter of the propeller, have straight sides, flat bottom, and not react with your ingredients. Mix at a speed that doesn’t introduce a lot of air into the material, or cause foaming. In my experience, you need at least 20 minutes at a speed sufficient to produce a nice vortex (but not much faster).

    For what it’s worth. Good luck.

    Thanks, i sought of gathered homogenize is where it breaks down soluble particles into the liquid mixture - stirring alone doesnt do this properly.

    You need a strong blade and mechanism that traps in particles to break them quicker. 

  • Dirtnap1

    Member
    March 7, 2019 at 6:16 pm

    You are correct. Mixing will not break down and homogonize as a high speed/sheer mixer/blades do.

    Mixing will keep product in suspension and help with hot spots etc.

    Homogonizing will form the emulsion (if making emulsion) and blends the ingredients together. 

    Really depends on your formula(s) weather or not you need to homogonize or simply mix. 

  • VitalikButerin

    Member
    March 7, 2019 at 8:04 pm

    Dirtnap1 said:

    You are correct. Mixing will not break down and homogonize as a high speed/sheer mixer/blades do.

    Mixing will keep product in suspension and help with hot spots etc.

    Homogonizing will form the emulsion (if making emulsion) and blends the ingredients together. 

    Really depends on your formula(s) weather or not you need to homogonize or simply mix. 

    Thanks, just a quick question…

    For example, i have a formula that says: 

    - first use homogeniser until disperse or for one hour..
    - continue stirring 
    - use propeller blade 
    - use paddle blade 

    my question is, why the specification on different blade? what do they do differently? 

  • VitalikButerin

    Member
    March 7, 2019 at 8:06 pm

    SkinNP said:

    Not sure what you are making, but I’ll give what I have learned so far and let others chime in to correct the record if they see fit. Stirring doesn’t mean you have produced a homogeneous mixture, but if you have homogenized then you likely did so by stirring (maybe agitation is possible in other contexts as well). So, when they say homogenize, I think they’re saying disperse ingredients evenly (presumably by stirring). No skin off my back if someone wants to differ with me on this.

    Mixing equipment is really important. Bad equipment will frustrate you, and make your results hard to duplicate. Make sure the shaft is true, the range of speeds appropriate, and the propeller shape and size appropriate for what you are aiming to achieve. I try to get the propeller to about 2/3 the depth of the material. The mixing vessel should be at least 3 times the diameter of the propeller, have straight sides, flat bottom, and not react with your ingredients. Mix at a speed that doesn’t introduce a lot of air into the material, or cause foaming. In my experience, you need at least 20 minutes at a speed sufficient to produce a nice vortex (but not much faster).

    For what it’s worth. Good luck.

    How can you tell if your mixing is going wrong? 

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