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SoapSap

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I just started using EDTA in my soap batter. I add 5 g dissolved in a little warm distilled water to a 40 oz. oil weight. I use a silicone loaf mold. I have made 4 batches in this manner, all with formulas I have been using successfully for a long time. I am getting some brittleness in the finished soap log. Could this be from the addition of EDTA? That is the only variable that I believe to be different. And I know I am not waiting too long to cut the loaf because the interior is sometimes a little too soft and drags on the blade. I stop and wait a day or two longer.
 

DeeAnna

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I have not seen brittleness in my soap with EDTA vs soap made without. But I have seen differences in hardness of my soap by using different batches of fat -- the fatty acid content of fats can vary.

Also some fats higher in palmitic and stearic acid (palm, tallow, etc) can make soap that varies in hardness depending on what portion of fat you use out of a container. Fat molecules higher in palmitic and stearic tend to crystallize out and settle. That's why the advice to always stir palm oil before taking some out for soaping. But I've seen the same kind of separation in tallow and even rice bran oil.

The proof of the pudding would be for you to make the same soap with the same fats and without EDTA and see what happens.
 

MySoapyHeart

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I only started using EDTA in my soaps in the very beginning of this year, as I wanted to add this in my soaps because many people I give my soaps too have hard water.

I have never encountered any brittleness in my soaps, and not after I started adding the EDTA either.
The only time I experienced brittle soap (this was before I started using EDTA) I did so because I accidentally added a bit to much Titanium Dioxide to a batch, and got a brittle and chalky feeling to the soap. Luckily it was a small batch. But other than that icident the EDTA does not cause any troubbles for me in my recipes. And I use a bit more than you.

PS. I don`t use palm oil in any of my recipes.
 

cmzaha

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I would not think using 0.44% would make a brittle soap, or that it would help much with chelating. But of course I have been known to be wrong and I go the Citric Acid route versus EDTA. I use Citric at 2% oil weight
 

DeeAnna

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From what I've seen, you don't need as much EDTA as you do citrate for chelating. About 0.5% by weight of dry EDTA powder works pretty well. That's generally what I use.
 

cmzaha

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^^^ Thanks DeeAnna, I was wondering about that. I just brought in some EDTA for my lotions so I will give it a try. What would you consider the max percentage of EDTA in soap?
 

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I already made like 4 logs with Irishlass solution and my soap is not brittle, rather the opposite, it'd cut so easy and smooth. Will see what is the difference between Edta and SC in a few weeks
 

IrishLass

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As with the others, I've never experienced brittleness in my soaps with the EDTA. I use it at .5% as per the total weight of my batch (as opposed to ppo).

As an aside to Carolyn- as with DeeAnna, I can attest that .5% tetrasodium EDTA works quite nicely. It might sound like a small amount, but it really works at cutting the soap scum down, and also helps my soap to lather better in our hard water. Having said that, though, I feel I need say (in case anyone should get the wrong idea that they'll never see one iota of scum ever again if they use EDTA), that although the amount I use makes a very discernible difference with my water situation in my home, it doesn't 100% totally eradicate every vestige of soap scum. I still do get some scum, but it's not as much as it used to be, and it's very easy to clean up.


IrishLass :)
 

DeeAnna

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Carolyn -- After some trial and error, I now use tetrasodium EDTA powder at 0.5% of my batch weight for almost all of my recipes. That's the same as Irish Lass. (Batch weight = fats + lye + water) Like IL said, EDTA doesn't stop soap scum, but it really reduces it.

For my last batch of laundry soap, I used 1% of EDTA powder based on batch weight. For a previous batch of laundry soap, I used 3% but I honestly can't say that much EDTA helps any more than 0.5% to 1%.

When I've put EDTA in the water and then added lye, the mixture turns white and thickens. The more EDTA, the thicker and more pudding-y it gets, so the 3% dosage was ... interesting. I'm sure EDTA does the same thing when I add it to my fats and then add the lye solution to that, but the mess is less obvious. :think: So I usually add it to the fats and SB it together.

I recommend making a solution of up to 39% EDTA powder in distilled water and adding the solution to the oils rather than using the powder directly. It's more convenient and you reduce the overall exposure to the powder in the air by making a master batch solution.

I subtract the water in the EDTA solution from the total water for the batch. There's enough water in the EDTA solution that the times I didn't do that, it affected the working time, tendency to gel, stearic spots, etc.

^^^ Thanks DeeAnna, I was wondering about that. I just brought in some EDTA for my lotions so I will give it a try. What would you consider the max percentage of EDTA in soap?
 
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DeeAnna

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Dahlia -- When I add EDTA to the water, I do what you do -- add the EDTA first and then the lye. Don't be surprised if the mixture turns white and possibly thickens -- just keep on soaping!
 

Dahila

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yes it turns like a milk first and a bit thicker but then become clear, kind of clear, I always add sugar to the water before lye but after edta, and the sugar gets a bit burned so the color is a bit tan;)) thank you Deeanna , so i just keep doing what i do :))
 

cmzaha

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As with the others, I've never experienced brittleness in my soaps with the EDTA. I use it at .5% as per the total weight of my batch (as opposed to ppo).

As an aside to Carolyn- as with DeeAnna, I can attest that .5% tetrasodium EDTA works quite nicely. It might sound like a small amount, but it really works at cutting the soap scum down, and also helps my soap to lather better in our hard water. Having said that, though, I feel I need say (in case anyone should get the wrong idea that they'll never see one iota of scum ever again if they use EDTA), that although the amount I use makes a very discernible difference with my water situation in my home, it doesn't 100% totally eradicate every vestige of soap scum. I still do get some scum, but it's not as much as it used to be, and it's very easy to clean up.


IrishLass :)
Carolyn -- After some trial and error, I now use tetrasodium EDTA powder at 0.5% of my batch weight for almost all of my recipes. That's the same as Irish Lass. (Batch weight = fats + lye + water) Like IL said, EDTA doesn't stop soap scum, but it really reduces it.

For my last batch of laundry soap, I used 1% of EDTA powder based on batch weight. For a previous batch of laundry soap, I used 3% but I honestly can't say that much EDTA helps any more than 0.5% to 1%.

When I've put EDTA in the water and then added lye, the mixture turns white and thickens. The more EDTA, the thicker and more pudding-y it gets, so the 3% dosage was ... interesting. I'm sure EDTA does the same thing when I add it to my fats and then add the lye solution to that, but the mess is less obvious. :think: So I usually add it to the fats and SB it together.

I recommend making a solution of up to 39% EDTA powder in distilled water and adding the solution to the oils rather than using the powder directly. It's more convenient and you reduce the overall exposure to the powder in the air by making a master batch solution.

I subtract the water in the EDTA solution from the total water for the batch. There's enough water in the EDTA solution that the times I didn't do that, it affected the working time, tendency to gel, stearic spots, etc.
Thankyou both. I am going to use EDTA in my next batch of soap. Sodium Citrate also does not get rid of all soap scum but sure helps
 

DeeAnna

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I haven't used citrate in my soap to compare it to EDTA -- too many things to try, not enough time! I'm curious to hear your perspective of how the two compare.
 

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