Boundary between HP and rebatch

Soapmaking Forum

Help Support Soapmaking Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

ResolvableOwl

Notorious Lyear
Joined
Jan 14, 2021
Messages
2,568
Reaction score
6,989
Location
Germany
Just another insignificant, probably slightly esoteric non(?)-issue about process nomenclature, without any practical implications.:rolleyes:

Definitions: HP = oils (triglycerides) + lye solution, saponified under constant heat supply in one step. Rebatch = solid soap reheated (possibly with water addition) until liquid(ish) and reworkable.

Idealised, the final state of either process is a more or less gloopy paste, that consists of fully saponified oils with no unreacted lye, and a similar, elevated water content, that will reduce during cure.

Now, suppose you rebatch since you have forgotten to add one oil. The soap had been solidifed lye-heavy, so you'll grate it up and liquefy it as best you can with heat and some extra water. Eventually, you add the extra oil to a hot, partially saponified aqueous soap/lye jelly – sounds like HP, heh?

On the other side of the scale, you can add a bit of shredded soap to HP batter before/during cooking (with the intention to dissolve it), or LS at the end of HP cooking to get the batter more runny – is this still HP, or is it rebatch?

How to call the process when I use half fresh oil+lye, and half grated soap?

What if I use an ingredient like mono- and diglycerides, that are, from their chemical structure, partially saponified oil molecules?

What if I stir the whole CO fraction of a recipe in form of pure, grated coconut soap (@Johnez' “sodium cocoate”) into lye, and then add the remaining hard and soft oils for a classic HP? What if I actually have found out this works decently? To some degree it circumvents some issues with the respective processes (HP: stable emulsion, quicker trace and saponification; rebatch: less uncertainty about burning and amount of water, late influence on superfat composition, better/faster heating through, lower final viscosity) at the price of some extra calculations and stash space.


Rationally, there is no boundary, but a continuum of intermediate processes between rebatching and HP. But the conventions of soapmaking language don't reflect this, and my “intuition” tends to make some distinction too. Is it the “intention” that makes the difference (“Do I want to make new soap?” vs. “Do I want to reprocess pre-made soap?”)?

What (except that I'm grossly overthinking this) do you think?
 
I wish I had the soap making chops to discuss this with some sort of experience, however I am highly interested in the intermediate phases, specifically mixing "old soap" with differing superfats or additives.

Anyways following for some good discussion!
 
HP is making soap from scratch. Rebatching is upcycling. Two different animals. Taking a lye-heavy batch of soap (regardless if it is HP or CP) because you forgot to add an oil and rebatching is still soap making.
 
Ha! I was having related thoughts with my recent fragrance test. Some of the fragrances got so hot through generating their own heat that they were solid and basically saponified within the half hour time slot I used for the test - at least, when I rinsed the residue off my gloves after poking them down, I got bubbles rather than grease. Do they still count as CP soap? The process was the cold process, but the result was not. 🤔
 
HP is making soap from scratch. Rebatching is upcycling. Two different animals. Taking a lye-heavy batch of soap (regardless if it is HP or CP) because you forgot to add an oil and rebatching is still soap making.
Yes. But what I'm “struggling” with (not really, it's a strict first-world problem) is how to call it when I forgot, say, 80% of the oils on purpose. A major part of the following treatment will be from-scratch saponification, but another major part is “upcycling” (is it still upcycling if the “scraps” were deliberately made for rebatching?).

@Tara_H Crazy. I wonder if there are non-fragrant magic additives besides EO/FO that can accelerate saponification to a point where CP becomes HP (with elevated volcanoing danger) by itself. I have crossed the border between CP(OP) and oven-borne HP more than once with a very generous oven setting. The boundary between “forcing gel everywhere” and “forcing saponification through gel phase” is blurry too.
 
hp_vs_rebatch_name.png

An attempt to depict my point. At some point, it isn't just no longer adequate to call a process “X modified/enhanced by Y”. Category conventions just don't provide a way to “smoothly” interpolate between the techniques, they always introduce some kind of artificial discontinuities (steps), that do not originate in the events that are actually happening, but only in our anthropocentric way of speaking about them in our human languages. Nature must not depend/does not care about how we call things.
 
How to call the process when I use half fresh oil+lye, and half grated soap?
I called it Old and New Soap when I first started doing that. As far as what process, it doesn't matter if it is HP or CP or a combination, which is very well may be. I've done it both ways. Confetti Soap is the more common term for what I called Old & New Soap. But I think it is legitimate to call it re-batch as well, if or when the intent is to make up for something lacking in the grated soap. I've done that, too. By using a nicer formula with the new soap to counteract the less than desirable effects of the old soap.

Rationally, there is no boundary, but a continuum of intermediate processes between rebatching and HP. But the conventions of soapmaking language don't reflect this, and my “intuition” tends to make some distinction too. Is it the “intention” that makes the difference (“Do I want to make new soap?” vs. “Do I want to reprocess pre-made soap?”)?

What (except that I'm grossly overthinking this) do you think?
I think you are overthinking this.

HP is HP, CP is CP. The two processes can be combined in a given soap, as in my example of Old & New soap, aka Confetti Soap. Why, they can even be combined in LS, but that is a whole other subject.

I wonder if there are non-fragrant magic additives besides EO/FO that can accelerate saponification to a point where CP becomes HP (with elevated volcanoing danger) by itself.
Alcohol, honey... in excess any heat producer is likely to speed up a batter that had to be created with more heat (high melt point oils, or just using a lye solution not cooled enough). I'd say that this can be done accidentally or on purpose, of course. So maybe you would discount that input since the additive that can create more heat is added to an already higher heat and you said 'by itself'.
 
But what I'm “struggling” with (not really, it's a strict first-world problem) is how to call it when I forgot, say, 80% of the oils on purpose. A major part of the following treatment will be from-scratch saponification, but another major part is “upcycling” (is it still upcycling if the “scraps” were deliberately made for rebatching?).

Why on earth would you deliberately forget to add an oil? That just makes no sense. You don't need an excuse to rebatch, there are lots of people who deliberately make soap to be reused; I've done it myself. Made a bunch of colored soap and shredded/cubed them for Confetti Soap...no different than making imbeds. And if you want to make Whipped Soap, you have to rebatch (as far as I know). But a lot of folks who rebatch do so because something has gone wrong with their soap...maybe the colorants did work out or the FO/EO completely faded away.

Except for wanting to try and make Whipped Soap, I don't Rebatch. If there is something wrong with my soap on a recipe level, I'll just toss the soap because the labor costs alone far outweigh the cost of the ingredients. If the issue with the soap is colorants or scent...it is far cheaper for me to donate the soap to my local homeless shelter or food bank, than it is to incur additional labor and ingredient costs. But it's a personal preference and I'm not going to put down anyone who rebatches.
 
Some of the fragrances got so hot through generating their own heat that they were solid and basically saponified within the half hour time slot I used for the test - at least, when I rinsed the residue off my gloves after poking them down, I got bubbles rather than grease. Do they still count as CP soap? The process was the cold process, but the result was not.

Cold Process doesn't mean that you soap stays 'cold' while it saponifies. The CP method uses the natural exothermic heat reaction created by combining fatty acids and lye solution during the saponification process to create soap. The HP method simply accelerates the saponification process by applying an external heat source...like a crock pot.
 
Not sure it helps, but I personally use the following "rules" to determine what kind of process a soap is made with:

CP -> soap is molded before gel phase (or no gel phase at all)
HP -> soap is molded after gel phase
Rebatch -> melting of already saponified soap (I consider confetti soap to be embeds in CP - although I can see why some would call it rebatch).
Anything inbetween I would call a hybrid soap (e.g. HP/rebatch hybrid)

I don't think there's a universally agreed upon terminology, this is just how I find it easy to distinguish soap techniques.
 
Just came out of the shower with a literal “shower thought”: Mixed HP and rebatch soap is molecular confetti soap. New and old soap mixed together – but unlike embeds and shreds (that are visible to the naked eye), the blending takes place in solution, on a molecular level, and the different constituents aren't even distinguishable with a microscope.

Admittedly, that's more a “marketing gag” name than anything else.
 

Latest posts

Back
Top