Soda Ash Experiment

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JustBeachy

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We were having a discussion, on a thread, about the different processes and how they effect the creation or lack of, soda ash. I volunteered to run a limited experiment, testing the difference in CPOP soaps, covered and uncovered vs refrigerated no gel, covered and uncovered. Here's the start of the experiment.

The basis for this experiment is being done using a Castille recipe, since that's the one I've done in the past that produced the most SA. I made a 6 lb batch, so all the batter would be from the same batch.

SA Test Batch 1.jpg

Then I poured into two split molds, having one side covered and leaving the other side open. Notice the extra mold? That's my super scientific brain, thinking of having a 5th test of regular blanket insulation. Well, ok not really. That's my extraordinary hatred of math that caused my batch size calculation to come out wrong. :razz: Still, might as well use it in the test.

SA Test Molded.jpg

One batch went in the oven, CPOP. One batch went into the freezer. The, mathematical anomaly test, went into the closet, wrapped in a beach towel.
 
This is the test at the 3 hour mark. My normal CPOP is a little different than most that I see on the net. I bake at 170 for around a hour, until I see a full gel. Then I pull the mold out of the oven, uncover it and allow to cool. That's the process I did on the CPOP test mold. The Freezer mold was left in the freezer for three hours, then pulled and unwrapped. These are the results so far. I notice what looks to be heavy ash on the CPOP uncovered side. Slight edge of ash on the CPOP covered. I notice no ash yet on either side of the freezer test and no ash on the "blanket" test.

SA test 3 hour mark.jpg

I'll check it again later this evening.
 
Ok, here's the soaps unmolded at 7 hours. One of the things I like about the molds I use, is I can get soaps out of the mold quickly. When I'm making my regular soaps, with Beeswax and SL, I can usually drop them out of the bottom in around 5 hours. Still too soft to cut, but it frees up my molds for another batch.

Anyways, CPOP results first. Not sure how much you will see from the pics. As first noticed, the uncovered CPOP had lots of ash. It stuck out like a sore thumb once the soap cooled and hardened. The texture on the sides is smooth on both tests, but the covered CPOP is smooth. The Soda Ash has left the uncovered CPOP rough feeling. Here's the pic.

CPOP 7 hours.jpg

The Freezer test is next. Neither of these loafs show any sign of SA. Both exhibit smooth finish on the top and the sides. It is obviously a lot softer and less cured than the CPOP. As evidenced from the craters of me poking it on the top to check it. 8)

Freezer 7 hours.jpg

Next is the Blanket test. The typical pour it in the mold and insulate it. It doesn't show up in the picture very well, but there is a light coat of SA on the top. You can feel the slight sandpaper feel when you run your finger over it. While it is fairly hard, you see the edges a little dinged up from me "banging"it out of the overflow mold.

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I would suspect that ash will show up on the freezer soaps as they continue to cure. The process has been slowed so that there is still lots of active lye in there. I CPOP mine with ISO alcohol on the top to prevent ash and it works the best imho. Keep reporting, this is an interesting experiment.
 
Next I tried some cuts to see how the bars cured, what the gel did to the inside, etc.

The CPOP at 7 hours and cut. No noticeable gel lines on either of the tests, covered or uncovered. I did notice more when i was cutting the uncovered, a rough feel on the sides as well. No drag marks from the cut on either soap though. Again, something I like about CPOP. Definitely stresses the need to cover the mold with saran wrap though. No Zap at test on outside of soap. Very light zap on the interior of the second and third cuts.

Left is uncovered, right is covered. Both CPOP

CPOP cut at 7 hours.jpg

Freezer Test was obviously way too soft to be cutting normally, but heck, this was a experiment. Defined drag marks from the cut on this soap, as expected from cutting too early. But again, besides the finger jabs, this test had a smooth finish on top and sides. There were obviously no gel marks on the soap, since I avoided the gel. And no signs of Ash on either of the tests. Good looking soap overall. Zap test was not too bad on the exterior of the loaf, but heavy zap on the interior of the cut piece. I stopped cutting this one after the initial cut.

Freezer cut at 7 hours.jpg

Finally the Blanket Wrapped test. I'm glad my math was off and I tested this one as well. The top of the Blanket soap definetly has a fine layer of SA. Not as gritty feeling as the uncovered CPOP, but it's there. On a colored soap, I'm sure it would have been very noticeable. The mold was not covered with Saran wrap, (wish my math would have been worse, I'd could have run double on this one too), and I would assume that's what caused it. Just my assumption based on experience of covering soaps and then Blanket insulating. them. Look at the partial gel ring in the center though. To me that was a one of the reasons I started CPOP'ing the majority of my soaps. But I have to say, the Freezer Test produced the same aesthetic results.

I cut the entire small loaf of the blanket test. 5 bars. The partial ring was all the way through and all of the soap still had a pretty good Zap.

Blanket cut at 7 hours.jpg
 
I would suspect that ash will show up on the freezer soaps as they continue to cure. The process has been slowed so that there is still lots of active lye in there. I CPOP mine with ISO alcohol on the top to prevent ash and it works the best imho. Keep reporting, this is an interesting experiment.

I tend to agree with you. Seeing how hard it was zapping, it was obviously still in full saponification. I think we'll see some ash by tomorrow, and it wouldn't surprise me to find the Blanket test soap with the Ash worsening.

I never do the alcohol spritz. Just CPOP covered and I can't remember the last time I had a SA problem.
 
It might be worth taking one of the non-gelled bars and wrapping it in Saran wrap until it is completely saponified, to compare it to a non-gelled one that is left out and exposed to air. I find if I cover my mold with Saran and leave the wrap on until saponification is complete (no zap for sure and sometimes I add a day on to that), there is no ash formation. I often unmold before it's done saponifying, but then I will wrap the loaf or the slab in Saran until there is no zap.

It's the exposure of lye to the air that causes ash in ungelled soaps so if you prevent air from hitting it, there should be little to no ash formation. However, I don't know why certain FO's seem to cause more ash.
 
Interesting experiment! Soda ash remains a mystery to me. In my early years of soapmaking, I got ash all the time, really thick, too. Now, I get it occasionally, but never as thick as before. What changed? Not my recipe, that's the same. I did start to CPOP, and to spritz the top of the log with alcohol. I know the alcohol helps, but even when I forget, I still don't get much ash. So I'm not sure, just happy not to see a thick coat of fur on top of my soap any more!

Here's a blog post that looks interesting. I bookmarked it to read later, I've just skimmed it so far. It starts off about using water discount as a design tool, but further down the page, she talks about water discount and ash. Interesting stuff. In case you'd like to take a look.........
http://auntieclaras.com/2014/08/intentional-crop-circles-water-discount-as-a-design-tool/.
 
Have you really? Even with gelling and all? For the oven, wax paper might work better- I have no idea what the melting point of Saran wrap is but I have found the lack of contact with air makes a huge difference. WHen I use wax paper, I use the little dribbles of soap on the rim to kind of seal it down. I have some bars now I was lazy with and didn't cover-totally ashy- and another set made a day later that I took that time to keep covered and not a smidgen of ash. Both were ungelled.

I suppose many people would not want to do this but if I'm making a loaf, I will set wax paper down in contact with the soap. This wouldn't work for fancy peaked tops obviously, but then I gell and take the wax paper off. My swirls still look okay and even micas in oil still come out fine but not perfectly flat, but I never have ash. I hate ash though so totally worth it for me.
 
It might be worth taking one of the non-gelled bars and wrapping it in Saran wrap until it is completely saponified, to compare it to a non-gelled one that is left out and exposed to air. I find if I cover my mold with Saran and leave the wrap on until saponification is complete (no zap for sure and sometimes I add a day on to that), there is no ash formation. I often unmold before it's done saponifying, but then I will wrap the loaf or the slab in Saran until there is no zap.

It's the exposure of lye to the air that causes ash in ungelled soaps so if you prevent air from hitting it, there should be little to no ash formation. However, I don't know why certain FO's seem to cause more ash.

Yeah did that right after the premature first cut. Same with the Blanket Test.:wink:

Here's a blog post that looks interesting. I bookmarked it to read later, I've just skimmed it so far. It starts off about using water discount as a design tool, but further down the page, she talks about water discount and ash. Interesting stuff. In case you'd like to take a look.........
http://auntieclaras.com/2014/08/intentional-crop-circles-water-discount-as-a-design-tool/.

That was an interesting read, thanks.

I have gotten serious ash with my cold process/oven process bars that were uncovered! I should try the plastic wrap!

I always cover mine with saran wrap, and it would appear, so far anyways, there is credence to it preventing the SA.

Have you really? Even with gelling and all? For the oven, wax paper might work better- I have no idea what the melting point of Saran wrap is but I have found the lack of contact with air makes a huge difference.

Saran wrap is fine in the oven. Some people use it while baking up to 325 degrees. I like your idea of dribbling dots of soap batter to help seal the edge.
 
Ok a quick update at the 24 hour mark. Sorry no pictures at the moment, having to run out and check on some jobs. I'll post some this afternoon.

The CPOP, The uncovered portion, is hardened and top is layered with ash. The covered portion is hardened, with no ash present.

The Freezer Test. Contrary to my belief that it would eventually create some ash, neither batch has any noticeable SA. The small section I wrapped after the premature cut, looks exactly like the other portions. Cut some of the loafs and no zap on any of the tops and/or interiors. Hardened out completely and was able to cut.

The Blanket Test. This batch still had the slight SA on the tops. What is interesting, is something that Craig pointed out on a different thread. On the cut bars that had a partial gel ring, you can see a distinctive circle from the partial gel. Outside of the circle, the ungelled part, you can see a layer of SA that stays within the lines of the gelled/ungelled area's, better than I ever was with crayons in kindergarten. :)

I'll shoot some pics when I get home later. Should be a short day, I'm fighting off a cold.
 
Here's the pics at around 30 hours from pour.

The CPOP uncovered is on the left. It shows signs of heavy SA on the tops, the side even had a slight feel to it. The CPOP covered, on the right, shows no signs of SA and is smooth on top and sides. The covered CPOP soap is smooth and has already hardened quite nicely, considering this is a 100% OO soap.

CPOP Tops.jpg CPOP sides.jpg

The Freeze Test was actually the most enlightening outcome for me. The tops on both look good, with no signs of SA. The sides looks smooth. Even the cut piece that I covered, while the soap continued to saponify, looks good. No signs of ash. I was expecting this one to ash over as the process continued. I have to assume it's not going to, since there is no Zap left at all on tops or interior. It did produce a smooth soap, like I've heard as a reason people refrigerate their soap. Well except for the obivious finger pokes and premature cutting. :D Uncovered is on the right, covered is on the left.

Freezer Tops.jpgFreezer Sides.jpg

Finally the Blanket Test. As noted earlier, there is a slight feel of SA on the tops of this soap. Since it was more of an accidental test, the idea that it was uncovered, (no saran wrap), makes me lean towards that as a reason it ashed. Not as bad, as the uncovered CPOP, but then again, it was wrapped in a beach towel, so that kept some air out.
Blanket Tops.jpgBlanket sides.jpg

I'm not sure if you can see it, but the feel was definite. As Craig pointed out in a different thread, the area on the side shot of this one that hit a partial gel, has soda ash on the outside, (ungelled) area, but not inside the gel circle.

Which throws a wrench into my results. I was able to produce ash by gelling uncovered. Non gelled soap didn't ash, covered or uncovered. Yet on the blanket test, the un gelled area ashed, and the gelled stayed clear. I would have said it was due to the ungelled portion continuing to process, yet the Freezer soaps didn't have that problem. Could it be a "temperature middle ground"? Hot covered at 170F (CPOP) was fine, Cold both covered and uncovered at below 32F, (Freezer), was fine. Blanket at an unknown exact temperature, was fine where it gelled, but on the "just warm" edges it produced some ash.

Leaning towards a reverse Goldi Locks theory, where too hot and too cold end up being just right. And the warm middle ground being the odd man out. Just a crude experiment though, no real proof, before all you professors start jumping on my science. hahaha
 
At the 48 hour mark there were no noticeable changes from the 30 hour mark. Not sure if it provided any definitive answers besides covering soaps with saran wrap is a good idea for CPOP and Insulated batches. And I'd say there is some merit in the Freezer technique.

End of my test.
 

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