Duplicating a Crystal Clear Algin gel

I'm trying to replicate an older version of John master's organic shine on treatment  and here are the ingredients.

Aqua (water), Glycerin*, Aloe Barbadensis (aloe Vera Leaf Juice) Gel*, Guar Gum*, Sodium Alginate, Daucus Carota Sativa (carrot) Seed Oil*, Olea Europaea (olive) Oil*, Calendula Officinalis (calendula) Extract*, Anthemis Nobilis (chamomile) Extract*, Xanthane Gum, Methylcellulose Gum, Macrocystis Pyrifera (kelp) Extract*, Marine Phytoplankton, Fagus Sylvatica (beech) Extract*

I'm struggling with the combination of gums especially because I don't know the grades used in the benchmark product.  The benchmark is perfectly clear and extremely thick (there's a lot of bubbles so I can't get a good viscosity but it stays in place even upside down) 

So far I am just playing with the base ingredients with ratios like this:

Water qs
Glycerin 10%
guar gum 0.3-0.5% (if I go higher the clarity of the formula is impaired)
Sodium Alginate 1-3% (this might be too much, I'm also wondering if there is undisclosed Calcium present in the product that is helping the algin gel)
Methylcellulose 0.1-0.2% (HV version approximately 4500 cps. in 2% solution)

The base is pilling from the amount of thickeners and it is not achieving the high viscosity I want. There are also plenty of bubbles in the formula but I think that's just a processing issue. I'm doing everything in cold water and using an overhead mixer with paddle blade.

So my questions:
Are my percentages just super far off or am I probably facing an issue with grades?

Do I need higher shear to incorporate the algin/methylcellulose, or should I let things hydrate fully and then mix?

Comments

  • PharmaPharma Member, Pharmacist
    You've got some calcium in the extracts...
    Why not try it by adding some? Alginate as far as I know is only used as real gelling agent together with calcium salts.
  • EVchemEVchem Member
    Yeah I made a 1% CaCl2 solution and was adding that to a revision, not sure how much is needed to cause the gelling because I added ~4% (so only 0.04g CaCl2- considering there's probably not much more calcium from the extracts than that)
  • PharmaPharma Member, Pharmacist
    That's not enough...
    1% alginic acid requires up to 0.57% calcium chloride hexahydrate for full gelling and sodium alginate requires about 0.5%. Partial gelling is possible with less calcium whereas more is useless or even counterproductive.
  • EVchemEVchem Member
    Hmm I'll play with it longer, @Pharma do you think the benchmark could just be using CaCl2 without listing it on the ingredients? I'm very skeptical that they were able to get the Ca needed from extracts alone, especially given how clear the gel  is. They also list guar gum even before algin, and the tests I'm doing with the guar I have now are not reaching that level of clarity. I suspect some of that is due to my processing but it's hard to reverse engineer this product when I'm doubtful of the LOI and I don't have enough experience with these kinds of thickeners
  • PharmaPharma Member, Pharmacist
    Probably they mistake calcium alginate for sodium alginate?
    BTW guar gum and xanthan have a very strong synergism! Used at the right proportions (try something between 3:1 and 1:3), you can create anything firm, nearly brittle, free standing gels ro more sticky, smooth or soft versions.
    Guar and xanthan come in a variety of qualities, some are more opaque than others.
  • EVchemEVchem Member
    could be!

    yeah that's definitely part of the issue I'm having- there are so many grades  of these gums and I'm limited to  whatever we can stock with low minimums. I've got an organic guar  and guar hydroxypropyltrimonium Chloride and then methylcellulose, xanthan gum in two different grades, and the sodium alginate. My original thought was that the methylcellulose and xanthan gums  are not the major thickeners here, but since the guar can work synergistically with xanthan maybe I should revisit that idea
  • PharmaPharma Member, Pharmacist
    I just found out that guar also shows some synergy with methyl cellulose. Dam, I hope you're up for some mixing :smile: !
  • PharmaPharma Member, Pharmacist
    edited June 17
    Did some thinking: Aloe vera gel is composed of glucomannan and acemannan. Why is this important? Glucomannans such as guar all show synergism with xanthan gum and in fact, I quickly found a publication showing synergism between aloe vera gel and xanthan.
    You've got a bunch of synergies with xanthan in your gel. That's going to be tough.
    What I also thought about: Synergies with xanthan rely on "saccharide-saccharide stacking" which is independent of calcium. It could be that the added sodium alginate serves mainly as rheology/consistency modifier. It might impart (just another educated guess) smoothness and softness to the gel. Hence, an alginate free version of your gel is probably having a "harder" ratio and not a "slimy" one.
    A third idea I had: The 1% line is maybe just after aloe vera gel. In other words, nearly everything in the composition might be in random order. Alginate is probably the most expensive gellant and hence possibly a minor one just added for a finishing touch whereas the cheaper ones (guar and methylcellulose) act as synergists with xanthan and generate the basis of the gel.
    Did you dry the benchmark product to find out the amount of water added (well, including aloe vera gel but that problem is solvable)? This dried product is likely to be not dry and give you an idea on how much glycerol is inside. Else, flocculation of the gellants followed by filtration and drying could be attempted to better separate the ingredients.
    Also, addition of EDTA or citric acid would destroy an eventual calcium-alginate interaction: A strong drop in viscosity is likely to prove that calcium has actually been added and that there's quite a high percentage of alginate in there.
    And a last one for tonight: Alginate gels, from my kitchen experience with an attempt at molecular cuisine tell me that they need to be hydrated and become crystal clear, whereas methylcellulose, I used that cellulose derivative only for tapestry and back in the day as student, are always opaque. But higher concentrations of glycerol can turn an opaque methylcellulose gel crystal clear.

  • EVchemEVchem Member
    Wow really appreciate your thoughts here! 

    The alginate might be at a lower percentage but the benchmark has this slick feel that made me guess it was a major contributor. I agree with your guess on the 1% line, I'm worried I will have to deviate  from that to get a similar product since I have limited options. 

    We used to have a scale that could handle loss on drying,  I should try with what we have here and see if I can get any usable results.  Dumb question but how exactly would I force flocculation? With a centrifuge?

    Good thought on the chelators as well- at least that will be an easy test.

    The alginate and methylcellulose I'm using are actually from a shop for gastronomy since they have the smallest MOQs.
  • PharmaPharma Member, Pharmacist
    You could add isopropanol or acetone to it. Xanthan gum will however tolerate 40-50% of these solvents. Depending on the degree of methylation, methylcellulose can even be fully soluble in pure iPrOH or acetone. Guar, alginate, and aloe should however precipitate at a certain amount of solvent. My failed attempt at making alginate jelly shots was due to precipitation already at 20-30% ethanol and I was aiming at 80 proof Cointreau shots.
    You could also heat up the gel to ~50°C: If memory serves me right, only xanthan gum will remain >90% gellified, the others should lose most of their viscosity.
    It might be easier to first dry it and than add acetone. Except for the methyl cellulose where you might not know the degree of methylation, all other gellants should precipitate as hopefully rather "dry" flocks and not gluey ones such as they likely would if done in the native product. Pass through a coffee filter you weighed before, wash with pure acetone, dry (not in the oven, because *BUMMM!*) and reweigh. That's the total amount of gellants (including aloe gel but minus more or less MC). No need to bother with what passes the filter because: Everything - stuff on filter = glycerol plus dry weight of extracts and some MC (extracts = likely negligible).
    Hope that helps!
  • EVchemEVchem Member
    I did a very rough test with the EDTA (i was very heavy handed, but that still shouldn't affect the other gums I think) and I saw a complete loss of viscosity-so that makes it likely that  the sodium alginate is the major gellant here right? 

    I'll still try the method you proposed and let you know if it works for me!  


  • PharmaPharma Member, Pharmacist
    Did you check pH? Too low a pH could also reduce viscosity of several gellants in there. Else, it'll mean that most is likely calcium alginate.
  • EVchemEVchem Member
    pH  last I checked was 6.7  I think the alginate and the guar are balancing    each other out. So you don't think its possible  they were using sodium alginate and  some kind of calcium solution to thicken? Would the sodium be exchanged for calcium?
  • PharmaPharma Member, Pharmacist
    Just that we don't misunderstand each other: You measured pH after the addition of EDTA when viscosity was fully gone?
    The job of EDTA is to "catch" calcium ions which otherwise would gel alginate. Hence, if adding EDTA (without changing pH too much) results in loss of viscosity then it means that they most likely added sodium alginate and calcium salts (directly adding calcium alginate is not as practical because it is already gelled). Can't be 100% sure but lets say 99.9%.
  • EVchemEVchem Member
    So I retested today and I didn't see total viscosity loss until I had added a significant amount of EDTA (almost 2%), however this raised the pH from 6.8 to 8.3. 

    I'm still drying my other sample out in the oven so can't test for non-water content yet. 

    On another interesting note, I also tried a sample with this ingredient:
     (ESP A+ Powder is an all-natural dry blend of Seaweed extract (Algin) and Aloe (200X Inner Leaf Aloe Vera powder) and Tricalcium citrate.  
    When I prepped it according to the supplier's instructions, I was able to obtain a very thick clear gel albeit with yellow tinge.  However when I added small amounts (0.1% each) guar, xanthan, and methylcellulose I noticed a drop in viscosity, even though the pH didn't change  much (from 4.6 to 4.8). I'm surprised at this, wondering if the gel will set back up over time or not, I'll make an  update if I notice any change!



  • EVchemEVchem Member
    Still updating in case anyone ever has this problem in the future.  So after  4 days drying my sample out in a 50C oven I lost  54.3% wt.  I filtered what I could yesterday and left out to air dry overnight but didn't lose much weight. If I'm understanding right,  I lost 55% wt so I'm looking at 45% glycerin + gellants? That seems high so I'm going to continue to filter and let air dry
  • PerryPerry Administrator, Professional Chemist
    Thanks for the update.
  • PharmaPharma Member, Pharmacist
    Dry at 80-90°C. Glycerol is hygroscopic and won't let go of water that easily.
    Correct, you seem to have 45% glycerol plus gellants.
    Why filter now?
  • EVchemEVchem Member
    @Pharma thanks! I guess I was worried that not everything was filtering out since the remaining % is so high but  sounds like it may not be dried out enough. We don't even have vacuum filtration here and the ovens are set, 50 is the highest I can go  and don't think heating on a hot plate will dry it out. I guess I could take the sample home to my own oven haha.
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