Some time ago, a wise person foresaw that, some day, I would explore how small a batch still would be able to volcano:
FWIW, I do HTHP — and it is not as scary as it sounds! The volcanoes are not uncontrolled, and are more properly called “expansions.”
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@ResolvableOwl I’ve never tried a small batch; sorry I cannot give any helpful tips there. But with your scientific approach to soaping, I’m sure you would do well with this technique!
Well, this day was yesterday. With mere 100 g oils, it wasn't very dangerous, but just fun to watch. More like a
mudpot (cute funny type of volcanism!). I melted the oils on a pot (probably a bit too warm), and after adding the still hot lye solution, it appeared to heat up, so I spontaneously decided to turn it into HP, and turned on the heating. It boiled like crazy, and I switched off the stove, but it just went on bubbling
though it barely covered the bottom of the pot. Well, after a minute or two, I scraped it into the mould, and wondered why it wouldn't give an even surface – well, it was bubbling and rising!
The fastest-moving batter I've ever witnessed. A few things to blame:
- As part of my current indigo vat trials, it had partially reduced indigo in it (no idea how this might affect trace), but it also had quite some fructose (sugar).
- But probably more important: I added 5.6% TOM of GSC (glyceryl stearate citrate). Well, it's not only a source of citrate and stearic acid, but also a strong emulsifier: It makes mixing the batter super easy (a few seconds with the spatula), but also promoted an intimate mixing of lye and oils – a good opportunity for the reaction rate to skyrocket. In normal soapmaking, there is very little emulsifiers present in the beginning – hardly enough to get a stable emulsion. It takes a few minutes (and often the convincing qualities of a stick blender) until the aqueous phase and the oils wouldn't easily separate from each other. But then the reaction picks up speed (gel phase) and eats through most of the saponification within half a day (CP) or one hour (HP). After 10 minutes, its consistency was like half through HP cooking, but without external heat.
My working hypothesis: GSC is a strong and lye-stable enough emulsifier for the lye and oils to disperse much more finely throughout each other. The point when enough conventional soap has formed to sustain the stable emulsion is much earlier, possibly within mere seconds after combining oils and lye.
So far I can't really recommend GSC for soapmaking. For one it does dissolve in hot oils, but the 5% solution became turbid again well above room temperature. I also didn't like that the oil phase foamed. And then this scary acceleration thingie.
Maybe at much lower rates it's a secret ingredient for the impatient to speed up lazy batters. But it's not realistic to use it as the sole source of citrate (a shortcut to get chelators into oils).
ETA: Pics, background, and updates in the indigo vat thread:
https://www.soapmakingforum.com/threads/indigo-vat-as-soap-colourant.84739/post-903763