Lye Masterbatch: Storage/Dosage Ideas

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ResolvableOwl

Notorious Lyear
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The idea of lye masterbatching has quite some appeal. Masterbatchers: What is everyone storing it in? How do you dose? Which tricks have proven, which don't work as intended?

I'm somewhat reluctant to just use a bucket and somehow spill the lye with a dipper/funnel into another container, just to weigh it, and discard (eww) or dump back (even more eww) the surplus lye. How does the everyday routine of lye masterbatch handling look like in practice?



A few ideas that might or might not work well and/or keep the lye from air contact (soda ash, evaporation/hygroscopicity, dirt) and/or meet my exceptional demands on laziness:
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Squeeze bottle (lab-grade, or ketchup/mustard-style, or the ones like used for mini drop swirl)

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Accordion-style foldable water tank

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Bag-in-box

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Dosing bottles (preferably the two-lid ones that are easier to refill)


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Bottle-top dispenser, Dispensette® (okay, that's slowly approaching rocket science)

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Couldn't one just use a good ol' soap dispenser bottle too?




(Am I overthinking this? Is this what overthinking feels like?)
 
The idea of lye masterbatching has quite some appeal. Masterbatchers: What is everyone storing it in? How do you dose? Which tricks have proven, which don't work as intended?

I'm somewhat reluctant to just use a bucket and somehow spill the lye with a dipper/funnel into another container, just to weigh it, and discard (eww) or dump back (even more eww) the surplus lye. How does the everyday routine of lye masterbatch handling look like in practice?

I LOVE master batching my Lye Solution...I make ready to use 33% and 35% so I don't have to worry about any math. Since I also MB my oils/butters, I have a spreadsheet with every mold and how much of each I need to fill it. Makes making soap easy-peasy.

Yes, you are overthinking it because you forgot the simplest container out there...Ye Old Food Grade 1-Gallon Jug. It should be noted that I don't make my Lye Solution in it. I have a heat-safe mixing bowl (w/handle and spout) that I only use for that purpose along with a funnel. Once the Solution cools down enough that I can pick up the bowl with bare hands, I then pour it in and then I store it in my soaping cart (rolling kitchen island) which is in the kitchen as you don't want it getting too cold (@DeeAnna can tell you why).

You want to make sure the lid is good and tight and wipe down the opening so lye doesn't build up and allow air in. I have kept my Lye Solution as long as five months without any degradation.

For MBing my oils/butters I use a 5-Gallon Food Grade Bucket (also kept in the kitchen). I have a commercial paint stirrer attachment for my drill that I use when I get ready to soap. Now I used to use a ladle and draw directly from the bucket, but my back isn't what it used to be and I would be hurting after a couple of soaps. So I use a 1-Gallon Food Grade Bucket that my husband fills for me and it sits nicely on the corner of my soap cart. I then just tare out my mixing bowl, ladle or pour in what I need and off I go.

It should be noted that I don't add any of my additives to my MBs...not that I use a lot. I honestly don't know if it would cause any problems...Sodium Lactate and Kaolin Clay...but while I don't mind the cost of a test batch gone wrong (maybe $5.00), losing a gallon of Lye Solution or 40 lbs of oils/butter is a heck of a lot more and it's no problem to just add it later.

Oh...I always wash out my buckets and jugs between batches and rinse well. Because I can't hand dry the inside of the jugs, I have several so I can let them air dry (upside down) and cap. While I don't think the same amount of tap water left from rinsing would hurt, I prefer not to chance it. And it's good manufacturing practice.
 
I mix in a dedicated (to lye usage only) HDPE container looking something like this:
1632155687165.png

I use the lid to collect evaporate (drips back into the vessel) after thorough mixing, the lid stays on until the solution is cool enough to decant into storage vessels. After cooling & before pouring, I weigh the full vessel to determine water lost through evaporate and add that much water back in. This size has a 2 quart capacity (close to 2 liters), which is enough for my usage rates. I do not trust myself lifting and pouring a gallon of milk, let alone a gallon of lye solution, since my recent hand surgery, so am glad I never started mixing a gallon of lye solution at one time. Others who still have their super-youthful strength can manage that, but I cannot. Also for safety reasons, I have always done my mixing of lye within the confines of my kitchen sink (vessels sit in the sink during the process) or plastic wash-tub if no suitable sink is available (such as when traveling).

For long-term storage, I use the same containers that I purchased lye from at some point (I keep and re-use these only for MB lye storage):
1632155800589.png


What I like about these containers is they are sturdy HDPE, already labeled for Lye and have very dependable child-proof caps, which do not allow any leakage even if I knock one over on its side. Then, for double safety, I keep the filled MB lye bottles in another larger plastic bucket just in case one of them ever springs a leak, which none ever has after repeated use over time. AND then that bucket is stored in a shower stall in a spare bathroom. If I had small children or someone in the home with Alzheimer's, another storage solution would be a locked cabinet, but there are only 2 capable adults living here, so this is a safe storage area in my home.
 
I use the lid to collect evaporate (drips back into the vessel) after thorough mixing, the lid stays on until the solution is cool enough to decant into storage vessels. After cooling & before pouring, I weigh the full vessel to determine water lost through evaporate and add that much water back in.

The things you learn. I will definitely be doing that with my next batch of lye. Thank you.


This size has a 2 quart capacity (close to 2 liters), which is enough for my usage rates. I do not trust myself lifting and pouring a gallon of milk, let alone a gallon of lye solution, since my recent hand surgery, so am glad I never started mixing a gallon of lye solution at one time.

I was just looking at stainless steel pitchers, but this is so MUCH better than using an open mixing bowl as I have been doing. No kids in the house, but I do have cats and they don't always mind. I can't life a whole gallon jug either anymore...age, along with having broken my wrist twice. It's why I only mix about 2/3s of a gallon and fill two jugs.
 
If you are talking about a dispenser that you would use for water or ice tea, I totally agree, I have yet to find one that last for more than a year.
https://www.amazon.com/Rubbermaid-0...ocphy=9052957&hvtargid=pla-311811030391&psc=1
these work well for me... I don't master batch that often anymore because I've slowed down production not having many shows, but I would keep a 50/50 solution in these for months at a time....probably at least a year overall.

what happened with yours after a year?
 
I use a (bought for the purpose) plastic petrol can to do the mixing in - it's reassuringly solid and red and contains the fumes well, although when the pressure seems to be getting high I do unscrew the lid a little bit to relieve it.
Once it's all dissolved and cooled I transfer it to 1l squeeze bottles without a spout - after some trial and error I prefer those for accurately measuring since I can slow down to a drop at a time.
 
lye_masterbatch.jpg

Okay, I've decided to jump in (on a pilot scale, for a start). I'll see how well it works (especially the dosage precision and the cap tightness). I dissolved the lye in a stainless steel pot, in a cold water bath to calm down the process. Of course a crust did build up at the bottom, but I just heated it up gently on the stove to get everything dissolved rather quickly.

What surprised me was how minuscle the evaporation losses were: I've started with 0.7 g more water than NaOH, expecting it to boil off during the most vigorous part of the dissolution/fuming, but no, I still ended up with 0.2 g excess water. So what. Judging from the appreciable soda ash clouds floating in the lye, it's about time to finish up that batch of NaOH anyway, it has seen better days in purity. Good time to not worry about percentage fractions of unplanned superfat bonus.
 
Really dumb question about masterbatching. I did a 33% masterbatch. When I use it, how do I calculate how much solution to use - just take the water amount from the recipe on the soap calculator of your choice? Or add the water and the lye grams?
 
You would take the water amount and lye amount from your recipe and add them together. Then you would take out that amount from your master batch, assuming your recipe is also set to 33%. It’s good to give the master batch jug a little shake prior, before opening it.
 
You would take the water amount and lye amount from your recipe and add them together. Then you would take out that amount from your master batch, assuming your recipe is also set to 33%. It’s good to give the master batch jug a little shake prior, before opening it.

Thank you! I did that, and my soap came out quite mushy. I hated them anyway, so I rebatched them, no extra water (no need - it was easy because they were so soft that I didn't need to chop them up - it was like rebatching soap dough) and they are OK now so definitely there was too much water that the rebatching removed. Who knows? Maybe a fluke of that particular recipe.

Anyway- thanks!
 
Or add the water and the lye grams?
Yes.

I did that, and my soap came out quite mushy.

Are you sure you did it right? I MasterBatch both my Oils/Butters and Lye Solution and my Lye Solution is 33% Ready-to-use. I have a worksheet on my wall that lists every mold I own and on it I have: Total Batch Weight, Oils, Lye***, FO. So it looks like this (all in ounces):


Mfg Mold TBW Oils Lye FO
BB 4" Silicone Square 20.37 13.75 5.76 0.86

*** - This the total of Water (3.86) & Lye - NaOH (1.90) from my Recipe from SoapCalc for that size mold.

All I do when I go to make soap, is give my Oils a good stir (I MB 40lbs at a time), tare my container, weigh out my Oils and toss in the microwave. While the Oils are melting, I get out my jug of Lye Solution, give it a good shake, and since it is Ready-to-Use, I don't have to do anything but tare my container and weigh out the amount.
 
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Yes.



Are you sure you did it right? I MasterBatch both my Oils/Butters and Lye Solution and my Lye Solution is 33% Ready-to-use. I have a worksheet on my wall that lists every mold I own and on it I have: Total Batch Weight, Oils, Lye***, FO. So it looks like this (all in ounces):


Mfg Mold TBW Oils Lye FO
BB 4" Silicone Square 20.37 13.75 5.76 0.86

*** - This the total of Water (3.86) & Lye - NaOH (1.90) from my Recipe from SoapCalc for that size mold.

All I do when I go to make soap, is give my Oils a good stir (I MB 40lbs at a time), tare my container, weigh out my Oils and toss in the microwave. While the Oils are melting, I get out my jug of Lye Solution, give it a good shake, and since it is Ready-to-Use, I don't have to do anything but tare my container and weigh out the amount.
I think so, but 🤷‍♀️.

This was my recipe. I added 146 grams of lye water. Maybe it was the recipe itself....??

(I MB 40lbs at a time),
👀!!!
 

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Thank you! I did that, and my soap came out quite mushy. I hated them anyway, so I rebatched them, no extra water (no need - it was easy because they were so soft that I didn't need to chop them up - it was like rebatching soap dough) and they are OK now so definitely there was too much water that the rebatching removed. Who knows? Maybe a fluke of that particular recipe.

Anyway- thanks!
Interesting, they probably just needed more time, but if you didn't like them anyway, then I am glad rebatching worked. I noticed that while my soaps are usually firm the next day (I use a 40% lye to water concentration) the soaps I made yesterday are still soft to the touch today, except the one with an accelerating fragrance. Then I remember that I had added extra water to make it a 34% lye concentration and did not force gel, plus the humidity is very high where I am, so all that combined I think will cause them to stay soft for a few days.
Another factor could be the fragrance, if you used a decelerating one.
 
You would take the water amount and lye amount from your recipe and add them together. Then you would take out that amount from your master batch, assuming your recipe is also set to 33%. It’s good to give the master batch jug a little shake prior, before opening it.

This is nagging at me. I added only the amount of water to the oils, not the lye and the water. I think I ended up with something that had less lye than it should have. What do you think?
 
@DianaMoon if you mean that you saw how much water your recipe needed, and you took that exact amount from your master batch, then yes, you used less lye than the recipe called for and that would explain the soaps being soft the next day.
To calculate how much less lye you added, you could play with the recipe in a soap calculator, adusting the superfat % amount, to see at what percentage you get the same total weight of lye and water. Not sure if I am explaining this right…
 
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