[evchem2]

I would say the only possible concern is maybe micro count, sometimes the food spec is higher since the products  generally have shorter shelf life

[evchem2]

I don’t know what specific grades of xg and HEC you’re using but they could be contributing to pilling (esp in combination with the starch and silica), can I ask why you’re using all 4?  

[evchem2]

I agree with what’s already been said- I  also think you could drop the coconut oil to  just claims level (0.01%), it’s not functional for your formula and will just make it harder to have clarity, require higher usage level of PEG-40… based on that benchmark I’d say your 1% line is right after the VP/VA

[evchem2]

We had a storage tank inline from our filtration/purification system- I’m not sure how storing in the production tank would work. You would probably want to validate you are able to totally disinfect the tank, maybe let some water sit in the tank for your worst-case timeline and test? I can see it being very demanding if you go that route so the second tank may end up being less costly in terms of time/ liability.

[evchem2]

I’d opt for liquid germall for preservation, but use level might be closer to 0.5%. Which form of vitamin E are you using? If it’s tocopheryl acetate it’s pointless and you should switch to tocopherol or eliminate entirely

[evchem2]

EGMS is also used for pearlizing, you may be able to get opacity from the fatty alcohols you have currently but not pearl.

[evchem2]

i couldn’t find anything comparing different acids but some suppliers have charts like you’re describing for their individual preservatives

[evchem2]

HDPE is high density polyethylene, it is polyethylene but has different properties than lower density

https://sciencing.com/differences-hdpe-plastic-polyethylene-plastic-6807965.html
https://omicoplastics.com/blog/ldpe-hdpe-similarities-and-differences/

[evchem2]

Is it very thick? Sea moss could be improperly labeled carrageenan which would not act as an emulsifier but maybe it could stabilize the system enough if the oil content is low. But agree with the others, they could just have left out the emulsifier altogether from the LOI

[evchem2]

@Anca_Formulator i see thanks for clarifying. I’ve never used the paddle culture, but isn’t it the same issue? The paddle’s been exposed to air for the past 3 months?  Even if the kit is not expired once you’ve exposed it I think the most reliable results are probably the ones after the ~120 hours/whatever the paddle supplier recommends.

[evchem2]

You’ve had the jug open for 3 months? I’m not surprised something would show up after continual opening and reuse

[evchem2]

What kind of zinc- particle size, coated vs uncoated? 
When you say it didn’t work, in what way- emulsion failed, desired effect not present at all or not present enough?

[evchem2]

You don’t have a lot of surfactant, so even though salt can help thicken it may not be enough to build viscosity like you’re hoping for. Did you make a salt curve for your formula? You also already have acrylates and HEC thickening, so why add salt on top?

I second Abdullah that Glycol stearate should have a better pearlescent look. You can also try heating your base and cooling slowly, this should help the glycol stearate form some larger crystals that create the effect you’re hoping for. If you don’t want to heat the whole base, you can buy a premade pearl blend for cold-process use, or try to create your own premix.

https://knowledge.ulprospector.com/5647/pcc-adding-pearlescence-in-cosmetics/

[evchem2]

@Farah - I’d say yes to overhead mixer before homogenizer. Being able to get different blades will allow you work on a variety of product types, the homogenizer can help with stability but I think  you can still achieve a lot without it. I do think you’re right about the stir bar solution mixing too, especially if you’re using xanthan and guar together. The tea sieve should work decently well

[evchem2]

@Farah yes the drill with its various blades would mimic what overhead stirrers do. For homogenizers they are really more rotor stator types (at least from my experience), the benchtop version is usually something like a silverson or a rotosolver.  Your immersion blender may replicate some of the high shear, but will also likely bring in air if you can’t control the speed.

[evchem2]

@Farah okay so I’d definitely recommend upping the oil used to disperse the gums, or (my preference) you can use any glycol (ex glycerin/ propanediol/ butylene glycol) to slurry. The glycols are all miscible in water, they’re humectants, and they can help the preservation of your product (lower water activity).  

I’d say with that equipment you are going to incorporate air very easily which is a problem for serums but even worse for any emulsions you may want to try in the future. If you have even a drill you could buy different blades that would provide different advantages and should reduce air incorporation (a prop style blade), or ones that provide shear would help mitigate clumping issues (Cowles type blade). 

The guar, xanthan, and acacia should all hydrate in room temperature water just as much as they would if heated. If you do incorporate too much air, you could use the heat to thin out your solution and stir carefully to help get some air out. Hope this helps- good luck!

[evchem2]

@Farah if you’re going to do the slurry,  a ratio of ~3:1 dispersant: gums  should be a good starting point- when you say it wasn’t easier to hydrate you mean you saw clumping? 

Maybe I’m missing something but why are you heating this formula? I believe all your gums are cold water soluble (aside from the flax mucilage)

[evchem2]

not as sole preservative if that’s what you’re asking (in combo with Euxyl PE9010  INCI: Phenxyethanol /Ethylhexylglycerin), but I did use it in a cream and it had a bonus side effect of reducing the soaping I was seeing. 

[evchem2]

Can’t really help on the filters, maybe look at some commercial reef safe benchmarks for inspiration? 
Are you looking for an exact replacement for Ganex or just another oil-soluble film former? Ganex is now sold under Antaron trade name, there’s Unimer U-15 from Givaudan, and Coast Southwest calls their Endicare® SC-530 an alternative to Ganex though it’s water soluble.

[evchem2]

Well I guess mpg is monopropylene glycol? That’s what I’d go with, I don’t think it will affect much

[evchem2]

Cab-o-sil is available from Amazon.. though I’m still a little warying of ordering chemicals off there. You can also use Aerosil 200  from Evonik , but I’d recommend wearing a respirator-like mask if you deal with large quantities

[evchem2]

These are all pretty different ingredients- what’s the purpose of adding any of these? Are you just trying to pad your LOI? 

[evchem2]

you could try PolySugaMulse D9, not sure how it would work at such a high use level. you should be wary of statements like ‘all natural’ though as your emulsifiers have been chemically processed.

[evchem2]

Prop mixers in general easily incorporate air, if you want to try switching to a different blade style you made find a cowles or jiffy blade works better for your system. Other tips and tricks include: moving mixer slightly off center from your batch, and periodically stopping mixing to let some larger air bubbles rise to the top (I’ve heard it called ‘burping’ the batch- when you restart do it at a lower speed if you do see some air come up).  When you do the final pour how high do you heat? Are you noticing these bubbles even when the stick solidifies?

[evchem2]

Not sure what you have access to but you could try other natural polymers like carrageenan or guar. Try cutting xanthan in half, I doubt you will totally eliminate flaking but that could help reduce it