I am familiar with what causes glycerin rivers but this is the first time I got glycerin rivers with this recipe and I have used this recipe several times with no problem. It is just that the glycerin follows the stroke of the chopsticks I used to try and drag down the blue color. The nightmare soap is the exact same recipe minus the FO and sodium lactate.
The temperature of the cold blooded didn't get any higher than 125°F and only for an hour. Then I shut off the heating pads and unwrapped it. Within a half hour it had cooled down to 118°F. It has me stumped.
From DeeAnna:
How can we make glycerine rivers?
So now that we have an idea of what glycerine rivers are and how they happen, what can we do to make them happen at will?
First of all glycerine rivers are NOT glycerine (or glycerin if that’s your spelling of choice). They are not “solidified glycerine” or “glycerine that develops in soap that goes through gel phase”. Glycerine – or glycerol – is an end product of the saponification reaction whether or not the soap goes through gel phase. Coldprocess soap with visible glycerine rivers is no richer in glycerine than a soap without rivers.
What the precise etymology of the term glycerine rivers is I don’t know, but the typical unpigmented river veins do look transparent like transparent ’glycerine soap’ – so maybe that’s how the term got coined. Today it’s an established and widely used term despite being a bit of a misnomer.
In this article DeAnna Weed explains what glycerine rivers actually are. They are the first fatty acid soap(s) to solidify when soap in gel phase gradually cools down over an extended period of time. Pigments and fine particles will migrate away from the solidifying soap and will congregate in the soap that’s still gelling. What we see as pigmented areas in a cut bar with glycerine rivers is the last soap to solidify in that bar. In practice those first soaps to solidify tend to be soap of stearic acid and soap of palmitic acid while soap of e.g. oleic acid tends to stay in gel phase longer. It’s a separation of soaps of different fatty acid content.
A diehard myth is that glycerine rivers are caused by titanium dioxide. They’re not. Titanium dioxide is a pigment with fine particle size and excellent opacity. It will congregate in gelling soap, move away from solidifying soap and make the crackled or veined appearance of the soap extra visible, but it doesn’t cause that structure.
The first prerequisite for making rivers happen is that the soap goes through full gel phase. In full gel phase soap molecules and pigments are mobile and can migrate to make the river patterns visible.
The second prerequisite is that the soap stays in gel phase for an extended period of time. In this article Kevin Dunn found that glycerine rivers become more pronounced the longer the soap stays in gel phase. In her article DeeAnna Weed maintains that slow cooling, i.e. slow, gradual transition from gel to solid is crucial for crackling to occur.
So we need to get the soap to gel and we need to get it to stay in gel phase for an extended period of time and to cool down slowly.
This is where water comes in handy. A high water content does not cause glycerine rivers directly, but as Kevin Dunn clearly shows in Scientific Soapmaking a high water content causes the soap to enter gel phase at a lower temp than a low water soap. Further more saponification is slower in a high water soap than in a low water soap, a high water soap stays in gel phase longer, and it moves out of gel phase more slowly than a low water soap.
