Worried about the texture of curing soaps

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SoapEh

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I'm hoping that some of the more long-time soapers can offer their opinions and/or experience here -- right now I'm definitely feeling the effects of being a noob :)

I'm somewhat of an experimenter. I've made a bunch of my own recipes (formulas? Blends?) on SoapCalc and tried a couple small batches of soap with each of them. It has been very interesting watching what happens to different types of oils as they cure, and finding out what textures I prefer.

Generally speaking, when I'm trying to formulate something or 'tweak' a recipe that didn't quite come out right I look for:
1) a hard bar -- I loooove a hard bar
2) a somewhat waxy texture -- I've learned that I love the way palm oil feels, especially with silk in the mixture
3) something that's easy on the skin; not highly cleansing (I stay under 15 if possible)
4) a quality I don't quite know how to quantify. I think of it as... flexibility. Opposite to crumbly, cracking, dry (which I've created by using too much clay). Palm-based recipes have this quality; they're hard without being brittle.

I make a recipe/plan, make soap, and watch what happens to it. Then I go from there. I have a few spots in the house where I'm keeping bars, to see if any of them cure differently -- we have a guest room that's above our garage and it's cold, with a ceiling fan on 24/7; that's where most of the soap is. I have little stashes in other bedrooms, the guest bathroom, the ensuite bath, and so far they all seem to be the same.

On to the TL;DR -->

A few batches of soap are... behaving a little strangely as they cure. Most of my soaps are hardish, then hard, and that's that. These ones are harder towards the outsides of the bars (which makes me hopeful that they'll harden up, eventually), but almost... springy and somewhat spongy in the middle. If you wanted to, you could push a dent in or even tear a bar in half (I did this as an experiment -- the soap was a weird texture in the middle).

They're not wet, not oozing, or sticky. They're stored on plastic, 1/2" apart, turned pretty often (every few days). The humidity in the house isn't unusually high or extremely low; our thermostat is set to regulate the humidity carefully since it's a new house and we need it to stay fairly dry for the first few years. The temperature is fairly cool -- most people who come over complain and put on a sweater but we're comfortable :)

Other soaps curing in the same place, made around the same time seem fine, which is what's stumping me. The ones that are behaving strangely are 40-55% olive oil, depending on the recipe, but also have harder oils/butters to round them out. I know high OO soaps have a long cure time, but I didn't think this necessarily qualified as *high* OO. Maybe it does!

Do olive oil/high olive oil content soaps go through a weird, spongy stage during the first couple of months of curing? I would love to hear that in a few months these are going to be gorgeously smooth, hard-enough soaps (I don't need rocks, I just need to feel secure enough to wrap them for presents and not worry they'll get DOS).

I'd wonder if my lye was weak, but other batches made with the same lye bottle are fine. One more piece of information -- all these soaps have some kind of additive. Most have oatmeal, some have kaolin clay, most if not all have mica, some have TD. I'm just not a plain-and-simple girl; I like patterns, swirls, and colours, and I like to play with texture, so... I'm all over the additives. I know that complicates things. Soap is so endlessly fascinating in its complexity :)
 
What size batches did you make?

I ask because small size batches require really accurate measuring of ingredients (particularly water) or the get soft or hard in parts. Softness weeks after being made sounds like too much water.

Did you use the water to mix colours? If you did was that water part of the recipe? Did you do overall colour or did you colour part of the soap? If it is the coloured parts of the soap that is soft then there might be too much water in those parts. You should account for all the water used in a recipe and it has to be proportionately equal in each part even if some parts aren't coloured.

Hardness or crusty hardness on the outside could mean over heating while saponifying, curing or CPOPing.

It's not the olive oil.
 
Interesting! When you say spongey/soft, my mind drifts to too much castor oil or sugar.

The low humidity might be contributing to the hard "crust" while the interior hasn't quite caught up.
 
I know exactly what you are talking about- I have had several bars that cure from the outside-in and can be split in half (with a sponge-y inside) after a 6 week cure.
These were my first soaps, before I was confident in increasing my lye to water amounts. So, I agree with PenelopeJane- could it be using too much or a high amount of water?
Also, these were also soaps that I probably stick-blended longer than I should have. I definitely poured them at thick trace. I thought that maybe the sponge texture might be little air bubbles or something? Like a froth? I have never made whipped soap or anything like that, but I wonder if SB too much could create a slightly different texture.
All of these soaps have cured for 8+ months now and are solid as a rock and are nice soaps. So, maybe just give them extra cure time and not worry about it.:)
 
SoapEh said:
A few batches of soap are... behaving a little strangely as they cure. Most of my soaps are hardish, then hard, and that's that. These ones are harder towards the outsides of the bars (which makes me hopeful that they'll harden up, eventually), but almost... springy and somewhat spongy in the middle. If you wanted to, you could push a dent in or even tear a bar in half (I did this as an experiment -- the soap was a weird texture in the middle).

Normal! I have a batch I made on November 24 when my cousin finally told me she wanted something for Christmas but she had trouble with scent.

The edges are hard, but as you push in at the center of the bar, it's a tad soft. Water doesn't evaporate evenly, and those outside areas have more surface area exposed to the air.

Things tend to even out over time, but it can take 8 weeks. I've never noticed soap being soft any longer than that, but a recipe with excessive water could be, I guess.

humidity carefully since it's a new house and we need it to stay fairly dry for the first few years. The temperature is fairly cool -- most people who come over complain and put on a sweater but we're comfortable :)

Again, normal, and a pretty good analog for our place (except that guests are always cold; we're comfortable. The current temp in my office is 65 and I'm fine).

Other soaps curing in the same place, made around the same time seem fine, which is what's stumping me. The ones that are behaving strangely are 40-55% olive oil, depending on the recipe, but also have harder oils/butters to round them out. I know high OO soaps have a long cure time, but I didn't think this necessarily qualified as *high* OO. Maybe it does!

And there's the last piece of the puzzle. Higher OO soaps take longer to cure. While I wouldn't call 40 to 55 percent "high," it's certainly higher than the average amount of OO I use--0 to 20%. Although I do occasionally make a castile.

Half OO is certainly going to take longer than a high-tallow soap, for example.

It'll harden, and get very hard, as long as the other half isn't something like castor, sunflower, safflower, soy, or canola. Those oils will tend to stay softer and stickier. If it's a mix of lard, tallow, palm, and coconut, even if with a little accent of castor, it'll end up hard enough to use in a slingshot.

during the first couple of months of curing? I would love to hear that in a few months these are going to be gorgeously smooth, hard-enough soaps (I don't need rocks, I just need to feel secure enough to wrap them for presents and not worry they'll get DOS).

In a few months, those are going to be rocks (assuming the recipe allows that, as I noted above). The Castile I made in June (and that I won't let off the drying rack until December 2018 ) is already rocks.

Most have oatmeal, some have kaolin clay, most if not all have mica, some have TD. I'm just not a plain-and-simple girl; I like patterns, swirls, and colours, and I like to play with texture, so... I'm all over the additives. I know that complicates things. Soap is so endlessly fascinating in its complexity :)

That's usually no biggie. That overheating oatmeal soap I was complaining about is already getting quite hard (it's mostly tallow). Other soaps with additives have been indetectably different from their plain counterparts in terms of hardness.

As long as it's not a large percentage, or a naturally extremely soft additive, you should be fine.
 
That soap will probably harden up in time. I made a batch with used fryer oil that was "vegetable oil" containing soy and canola, I assumed equal parts. I used 80% of the vegetable oil and 20% soy wax at zero superfat, then added 5% of the original weight in lard as superfat.

The bars were soft for quite a while, but have now become quite hard and waxy. Will be using another one in the shower soon once I use up some tester bars, I expect it to last longer than the first one.

In spite of being a bit soft initially, all that highly unsaturated oil makes a very nice soap, I've gotten some compliments on it. Very conditioning, and it doesn't have even a faint whiff of doughnuts....
 
Normal! I have a batch I made on November 24 when my cousin finally told me she wanted something for Christmas but she had trouble with scent.

The edges are hard, but as you push in at the center of the bar, it's a tad soft. Water doesn't evaporate evenly, and those outside areas have more surface area exposed to the air.

Things tend to even out over time, but it can take 8 weeks.

This is not normal. There is something wrong with the recipe or method both of you and Soap EH are using. I make heaps of 100% OO and it is ready to cut in 24 hours and hard all the way through in 48 hours. I also always use high percentages of OO.

When they talk about OO soap taking a long time to cure it doesn't mean it takes a long time to get hard. It gets hard almost straight away but if you use it in the shower before it has had a long cure it will get soft quickly.

These problems can definitely be fixed. You just have to tweek your recipe or your method. If you give us your recipes and method we will be able to help both you and Soapeh.
 
Mine's very easy. 100% OO. 3% super fat. Circa 30% lye concentration. No color or fragrance. 1 tsp honey. Keep cool to suppress gel.

Four days to decant without losing bits at the corners. Cut on the fifth day, usually. Cure eighteen months before use. Except that I've been told that my timing is actually very normal, and most of my soap isn't fully hardened at the center until at least the 2 week mark--except high CO or high tallow soaps, or heavily CPOP-ed.
 
Mine's very easy. 100% OO. 3% super fat. Circa 30% lye concentration. No color or fragrance. 1 tsp honey. Keep cool to suppress gel.

Four days to decant without losing bits at the corners. Cut on the fifth day, usually. Cure eighteen months before use. Except that I've been told that my timing is actually very normal, and most of my soap isn't fully hardened at the center until at least the 2 week mark--except high CO or high tallow soaps, or heavily CPOP-ed.

If it were me I would up the Lye concentration, use pure OO not pomace (if you are using it). I use honey in other soaps (not my castile) I mix at about 105*F and I always CPOP (very low temp turned off before the soap goes in just to encourage gel and hold the natural temp of the soap as it saponifies).

Are you suppressing gel because of the honey? That small amount of honey shouldn't effect the soap.

You will be able to cut at 24hrs and it will be hard.
 
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I'm sure that would help, but I'm not generally in a rush. Particularly with a Castile that will spend eighteen months curing no matter what I do.
 
Wow... thank you all SO, SO much for the responses! So many things to think about. It all just re-confirms that this 'hobby' has a lot of science behind it, and there's loads to learn.

So... I went back and looked through my notebook. The two batches that I'm pretty sure are not going to recover from this weird spongy thing they've got going on were both made in early October so they're about 9-10 weeks old. They're both from the same mixture, which was one I tried out early on -- weirdly, it did work beautifully with another batch but more on that in a second. Here's the mix:
55% Olive oil
20% Coconut oil (76*)
15% Shea butter
10% PKO
6% super fat
And... I may have found part of the issue. I hadn't yet learned about soaping at a 2:1 water:lye ratio. I was using water % of oil weight (I know, I know) and my lye concentration was 2.37:1, or 29.6%. Now I soap at 2:1, ~33%, which is much different.

I looked through the notes and whacked my forehead. One of the batches is a 2lb (oil weight) batch, and has eight separate colours -- I was feeling ambitious and wanted to make a fun, colourful, swirly soap. BUT... I have noted that, like a dolt, I mixed *each* little cup of colourant with a little oil, adding a total additional ~0.75-1oz of olive oil to the batch. Now I would take that from the batch, but then I didn't know it mattered.

The batch I have that used this mixture that did work out was a larger batch -- for some reason I felt possessed to double the batch size, probably so I could play with a new mold that holds just over 4lb of soap. Because I a) added clay, oatmeal *and* cocoa (all dry, water/oil-absorbing things) to that larger batch, b) used quite a bit of TD, c) didn't add extra oil, and d) soaped hotter, that batch gelled. The little batches didn't. The bigger one WAS somewhat funky-textured, but has hardened and smoothed out to something I'd call acceptable. It's nothing I'd write home about, but it's decent soap with an even texture.

So the two small batches are higher water, probably have slightly too much oil (especially considering the initial 6% superfat), but they ARE improving over time so I'm not giving up yet. A while ago I basically tossed them in a corner with some over-clayed soap that I don't yet know if I can rebatch into something useable and told them 'you have six months to become decent soap, or hit the garbage can'. I'll visit and turn them periodically.

Other soaps that were/are *slightly* soft (to my very hard-bar loving touch) that were made a few weeks ago seem to be sorting themselves out. Those ones are much more balanced recipes, with more hard oils and a better overall recipe profile. They were also made using a 2:1 ratio, so they have far less water to lose, and I know now to premix micas/colours with oils from the batch or be *very* sparing with oils I add in.

You guys are all awesome. In the end I think threads like this are rather like going to a therapist - half the time we ask a question, and then solve our own problem (or part of it) but couldn't have done it without the more experienced help looking on :D
 
And... I may have found part of the issue. I hadn't yet learned about soaping at a 2:1 water:lye ratio. I was using water % of oil weight (I know, I know) and my lye concentration was 2.37:1, or 29.6%. Now I soap at 2:1, ~33%, which is much different.

That would be just fine, actually; early on, I was using water as oil weight at 38%! Then add a bit more water for water-dispersable colorants.

It does take a bit longer to cure, but cure it does.

noted that, like a dolt, I mixed *each* little cup of colourant with a little oil, adding a total additional ~0.75-1oz of olive oil to the batch. Now I would take that from the batch, but then I didn't know it mattered.

OK, that one might not cure so well. :) Even 6 oz of extra oil in 2 pounds is a super fat of nearly 19%.

However, all is still not lost. You could re-batch that 2 pounds, add in the requisite lye to saponify 6 oz of olive oil, and re-cure. It'll take a while, but it'll end up usable at home, at least!


corner with some over-clayed soap that I don't yet know if I can rebatch into something useable and told them 'you have six months to become decent soap, or hit the garbage can'. I'll visit and turn them periodically.

One rebatch that I did, I added way too much water to. It was actually wet. Very wet.

It took more than six months to become decent soap, but it did.

And for Castile, six months is just the starting point. So very high olive recipes might require a full year...

Really, there's an incredibly wide range of acceptable and arguments of lye concentration are...well, not all that significant in terms of normal ranges. I don't hesitate to increase water if I need to slow down the recipe, or I want it to gel thoroughly. Nor do I hesitate to water discount a lot if I want a faster moving recipe, want to suppress out gel phase, or am going to use a lot of water-soluble colorants and know I'll end up with water there.

I do wish DeeAnne would weigh in here as she's done a lot of testing and measuring with curing times of various water levels.
 
Ack, I wasn't clear (surprise) -- I only added a TOTAL extra ~1oz, not 6oz extra oils. That *would* be a lot of extra oil, holy cow!

That swirly, oily batch is so bizarre; it may fix itself yet. I have no hope at all for its funky little curing partner, which just seems to be getting... spongy-er as time passes... but the swirly ones, some of the bars seem moderately okay. Who knows, we'll see - maybe, like the person who posted about their super-aged salt bars being fantastic after a long, long cure, I'll post in a year or three and say 'hey! check out the previously weird soap that's now the best thing I've ever made!'

Hope springs eternal.
 
I would rebatch the too much oil batch sooner rather than later. Soap with too much oil gets more difficult to grate and melt down the older it gets. I know this from personal experience. If you are wanting to save it, that is. I might would even make confetti soap to donate to a shelter or something with some new soap batter with a lower superfat to balance it out. Maybe a 1-2% superfat, depending on how much extra oil you think you added.
 
This is not normal. There is something wrong with the recipe or method both of you and Soap EH are using. I make heaps of 100% OO and it is ready to cut in 24 hours and hard all the way through in 48 hours. I also always use high percentages of OO.

When they talk about OO soap taking a long time to cure it doesn't mean it takes a long time to get hard. It gets hard almost straight away but if you use it in the shower before it has had a long cure it will get soft quickly.

These problems can definitely be fixed. You just have to tweek your recipe or your method. If you give us your recipes and method we will be able to help both you and Soapeh.
Soap that has overheated but not quite seperated (alligator teeth) or eruption into a volcano can leave a very soft spot in the middle of soap that can takes months to harden up. I have had it happen and the soap is fine after 4-6 months of curing. Using high water/low lye concentration is many times the culprit
 
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Soap that has overheated but not quite seperated (alligator teeth) or eruption into a volcano can leave a very soft spot in the middle of soap that can takes months to harden up. I have had it happen and the soap is fine after 4-6 months of curing. Using high water/low lye concentration is many times the culprit

Ok, thanks, I haven't experienced that yet.

I have lots of early soaps that I used too much water in all or part of the mix (to mix colours etc) and they got hard eventually but when you start using them the parts with too much water get soft quickly. Even 2 years old. So the soap usage is effected.

Also, I hate partially gelled soaps. That centre part cures at a different rate and leaves a dip in the soap. When you use it it dissolves at a different rate so you get part of the soap softer than the rest. So to me it's not just "cosmetic" as it also effects the soap usage.

For my recipes accurate measurements, equal portions of water (or oil) in all parts, a sensible water ratio and properly gelled soap makes a hard bar that lasts longer.

But I'm not one of those artistic people who slap a bit of oil in with a bit of lye and chuck in a bit of colour and lo and behold the most superb soap is produced. :)
I have to work at it.
 
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