TD and Breakage

[artemis]

Anyone else have trouble with TD causing the soap to break as you cut? I am using Nurture's water soluble TD. I use it at or below the recommended "dose": 1t ppo. This seems to only happen when I use TD to whiten the main portion of batter. When I'm only using to lighten other colors I don't really have a problem. More details below.

The facts:
40% Lard
30% Olive
20% Coconut
10% Avocado

A little salt, a little sugar

Green oxide, atomic orange mica, TD

Cucumber Melon FO (Nurture)

16 oz silicone loaf mold, soap cutting blade (straight)


Process: I measure the water, added the sugar and salt, then the NaOH. Decided to put my TD in the lye water (just a half tap this time for my 16oz batch). I melted, blended my oils. I added the FO to the oils-- no A, no D. In fact, I think it slowed trace a little. Separated a little for the colors. Just a simple drop swirl. No troubles. It was a little runny when I put it in the warm oven, but nothing I haven't seen before.

Trouble: It was too soft at bedtime, so I left it until first thing this morning. With each cut, the loaf is left nice and smooth, but the resulting bar breaks at the bottom. I turned the loaf & cut upside down, breaking the top of that bar. So, each bar has a pretty side and a broken side.

 

[shunt2011]

Your recipe is very close to mine, How long do you wait to cut it? I use quite a bit of TD and haven't experienced this. Or maybe too long? It may be the blade causing it too/sticking. I've had a couple that were a bit heavy on the TD stick to my silicone mold and break kind of like your photo if unmolding too soon.

 

[artemis]

I check it and cut when it seems ready? I often soap in the evening, which means I sometimes can't get to it until I get up in the morning. Today, it was hard enough to remove. One little corner did stick to the mold. The rest came out cleanly. I wet the blade a little so that it would slide right through. Which it did, but when I pulled it away, that edge just came away with the blade. But, only at the end of the cutting "stroke".
ETA: they seem nice and hard to me. No indentation when I press. They we're not gummy on the blade.

 

[shunt2011]

I use wire cutter but when I used a blade I would have that happen a lot. I soap later in the day myself and cut the next day. Are your soaps gelled or not gelled? Maybe someone else will have an idea. Probably related to the TD. I too use water soluble but from Nature's Garden.

Beautiful swirls/colors by the way.

 

[Martha]

I cut my soap with a knife that has a thin blade. I kind of slide the soap off the blade instead of pulling it away. The soap wants to stick to the knife, so maybe if you are pulling it off that’s enough to break it.

 

[DeeAnna]

In my experience, titanium dioxide makes my soap more brittle. It's especially obvious when I use TD in the main portion of the batter and if the soap itself is on the brittle side even without TD. My recipes are usually 50% or more lard and more like 10% coconut oil. Soap from these recipes are usually not brittle even when I put TD in the main soap. But TD has caused problems when I make recipes higher in coconut or if I use a moderate amount of tallow, either one of which makes the base soap more brittle than my norm.

A knife has a wedge shape that levers the soap apart because it creates sideways pressure. A knife will often cause this kind of breakage in brittle soap as the blade gets near the bottom of the cut. A bench scraper (dough cutter) is flat, so it doesn't create as much sideways pressure. If you use a knife to cut your soap and get this kind of cracking, try a bench scraper or other thin, flat cutter. Or a wire cutter. And I'd also cut sooner.

 

[artemis]

In my experience, titanium dioxide makes my soap more brittle.

I hoped I wasn't the only one!

A knife has a wedge shape that levers the soap apart because it creates sideways pressure.

I am using one of the soap cutting blades, which does have a wedge at the edge, but is straight the rest of the way. I did wonder if a wire cutter would be better. Since soaping is only a hobby, that purchase is on the back burner for now.

 

[earlene]

When you remove the cut soap slice from the blade do you pull it away from the blade forcefully? I have found that if I rotate the soap in a sort of circular motion sliding it off the blade that it comes away without tearing off part of the soap as you have in your photo. I also heat the blade with very hot water, dry the water before slicing, thus the blade is hot, but not wet. And I clean the blade between slices. That's when the soap seems fragile enough to crumble when slicing with a blade rather than a wire cutter.

Even with a flat pastry scraper that I use, which has no wedge the way a butcher's knife does, without the twisting motion to get the soap off the blade, I can get a rough bit like you have. Sometimes it's the ingredients, and sometimes it's the timing of the cut.

 

[jcandleattic]

Your recipe is very close to mine, How long do you wait to cut it? I use quite a bit of TD and haven't experienced this. Or maybe too long? It may be the blade causing it too/sticking. I've had a couple that were a bit heavy on the TD stick to my silicone mold and break kind of like your photo if unmolding too soon.

This is what happens to me. I use a premade TD base I assume is in a glycerin base (I'd have to look again to be sure) but if I unmold even just an hour or so earlier than it's ready it will break off like that. I just assumed it was due to not gelling or something not the TD but that's something I'll take into consideration next time it happens, because now that I think about it, it only happens bad like that when I use TD in the main base as a white based soap.

 

[Meena]

Anyone else have trouble with TD causing the soap to break as you cut? I am using Nurture's water soluble TD. I use it at or below the recommended "dose": 1t ppo. This seems to only happen when I use TD to whiten the main portion of batter. When I'm only using to lighten other colors I don't really have a problem. More details below.

So, each bar has a pretty side and a broken side.
View attachment 35935View attachment 35936View attachment 35937

Looks like what happened to my soleseife, and the same texture on the inside of the soap at the broken spot. I was told that my problem looked like the batter overheated in the mold, and that I also may have cut a bit late. FWIW

 

[penelopejane]

Looks like what happened to my soleseife, and the same texture on the inside of the soap at the broken spot. I was told that my problem looked like the batter overheated in the mold, and that I also may have cut a bit late. FWIW

I think that was me and the reason is because I don't think the texture of the soap where it is broken (last two photos in artemis's OP) is normal.
The only time I have had soap of that texture was with 100% OO soap (no TD used) when I was trying to come up with a way to force gel without using an oven. I put the soap in an esky (cooler) and it overheated and caused that hard texture and white parts. Maybe it is normal for lard soap but as I don't use it I don't know.