# Did I make calculation errors with this recipe?

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#### earlene

##### Grandmother & Soaper
Did I make vinegar calculation errors with this recipe?

Backgound: For the 'annual New Year Castile project' I chose to do a few variations so I can later evaluate the differences, if any for the various variations. I have discovered I like using some vinegar in place of water in some of my recipes, so thought I'd try it in a Castile soap too. I have read about all the posts here at SMF on using vinegar in soap that I can find, and used topofmurrayhill's mathematical formulas as my guidance. I have a cold, which didn't seem too bad until this morning, but I made the soap yesterday afternoon/evening, so my mind may have been working at less than optimal conditions and I fear I may have made some calculation errors. The gelled soap in question is sweating some lye water (zap test positive on the water sweating out of the soap).

Recipe:

Soapee.com used for recipe basics, then additions/adjustments done to accommodate the vinegar calculations

0% SF (my choice)

2.821:1 Water to Lye Ratio - I wanted full water and adjusted it so I wouldn't end up having to add lots of extra water to offset additional NaOH (using topofmurrayhill's posts on vinegar as my guide for how much vinegar & additional lye to use) This resulted in a

[26.2% Lye Concentation]

1.82% SA is my goal (because with this size batch it seemed to work out better than when I tried for 2% - that is unless my calculations are off - so I wouldn't have to add a lot of extra water or wouldn't have enough water)

500 grams oil:
250g pomace OO (Ambrosia®) +
250g 'pure' OO (Daily Chef from Sam's Club)

67.4g NaOH Lye per soapee +
+4.1665g (I rounded to 4.2) - to offset the amount of vinegar used
71.6 g total NaOH

Using my masterbatched lye (50% NaOH:50% water) the total came to:
143.2g (mb lye)

124.1g Vinegar (5% acetic acid) = 500g x 0.017 x 14.6 = 124.1 (using topofmurrayhill's calculations for how to arrive at desired percentage see this thread)

10g EDTA added for batch size at (*784g x .005 x 2.564 see this post by IrishLass for how I arrived at this.) (39% solution of EDTA has 61% water, so 6.1g of this solution is actually water)

30g Lavender EO (6% - I want to see how it holds at a slightly higher rate than the suggested 5%, plus I anticipate evaporation over the 1+ year curing time)

Soaped at room temperature.

143.2 + 124.1 = 267.3 of liquid solution of lye + water + vinegar
Soapee says my lye solution should weigh 190 g + 67.4g = 257.4 g

So my solution appears to be 9.9 grams heavier than soapee suggests, but that is before considering the SA and water in the vinegar.

Deduct 8.5g of SA (Sodium Acetate) and then I have an extra liquid weight of 1.4g.

Topofmurrayhill suggests that vinegar is 95% water and that one can calculate to add in the extra water, which for 124.1 grams of vinegar means I would need an additional 6.2g water. I already had 1.4g extra weight so suspected that the additional 4.8g would not really be critical.

Then I remembered that because I added EDTA solution, I actually have an additional 6.1g water, which I added to the oils and not the lye solution.

Therefore I was glad I did not add in the additional 4.8g water and believe I should have 1.3g extra water (or thereabouts if my measurements on my scale are accurate.)

My scale measures to 0.1g accuracy, but I haven't calibrated it recently to verify its current accuracy.

My weights could be slightly off, but how are my calculations? Did I end up with the 0% SF I was going for and are my vinegar calculations on target? If not, how bad is it?

Below is a photo before & after unmolding. It shows the lye water sweating out of the soap. I CPOP'd in a pre-heated and turned off oven (turned off before putting the soap in the oven) overnight with a couple of light kitchen towels to conserve the heat inside the soap. The temperature of the batter before going into the oven was about 80F. Oven was at about 150F when I turned it off and before putting the soap into the oven. When it came out of the oven this morning it was about 90F, so obviously it gelled while in the oven for at least 8 or 10 hours.

_______
* Yes, I realize my batch size for calculating EDTA is slightly off. I used the original number from Soapee, but when I total the additional weight, the difference is negligible.

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#### earlene

##### Grandmother & Soaper
Well, in the time it took me to write that up, have breakfast, do a little tidbits here and there, say about 4 or 5 hours after unmolding, it stopped sweating bullets. I mean lye water. It is now cut and although it's pretty firm, still somewhat impressionable and feels really cold to the touch through my gloves. Probably from all that water inside the soap as it continues to cool down to room temperatures, which in my house is in the mid-60's.

I do still wonder if my calculations are on the mark or not, as if so why would the soap weep lye water after gelling?

I should have mentioned it was a silicone mold.

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#### Steve85569

Supporting Member
Looks like your water to lye ratio was right about 2.9 : 1 which makes for a lot of water in a Castile. That would explain the sweating. I would say that it'll be a long cure time but then it is Castile. Your bars may warp as they dry because of the elevated water content to start with.

Just my two cents worth.
Please don't take anything I say as criticism in any way.
Besides this gives you an excuse to make another batch using a lower water content.