The “M” Challemge

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Notorious Lyear
Jan 14, 2021
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Self-imposed challenge: Make soap only with ingredients whose names start with a specific letter.

Self-imposed loopholes: Ingredients that are necessary for technically legit soap (lye, antioxidants, chelators) are allowed to start with other letters. And: It is permitted to choose the language for the names of the ingredients.

My choice: M (language: German)


  • Oils: macadamia nut oil, corn oil (de: „Maiskeimöl“), mango butter, murumuru – 25% each (plus ROE)
  • Liquid: almond milk (de: „Mandelmilch“) – full water replacement
  • Additive: lactic acid (de: „Milchsäure“) – 2%TOW sodium lactate, in the hope it would help with HP batter fluidity 🙄
  • Additive/fragrance: mastic resin – 1.5%TOW, added to half of the batch
  • Process: HP microbatching
First step was to obtain some almond milk:
100 g almonds + 1.3 L water (soymilk machine to an avail)

I dissolved the NaOH in the almond milk first, and only then the lactic+citric acid, to avoid weird curdling of the almond milk. It turned out that the almond components didn't bother to flocculate in strong alkaline either. 🤷‍♀️
Anyway, the lye still hot and the oils molten (put aside a small amount for post-cook superfat), it was time to combine them into a batter. Or, to be precise: two (but that was mainly due to my unfortunate choice of beakers to stew the batter in.)
Later on, split containers would be needed for the mastic/no mastic phase anyway, and so the batter was split in the first hour of cooking as well. I just wanted to follow the cult of HP microbatching as preached by @Bubble Agent and @Johnez!

To much surprise, it turned out that, though PP plastic (formally heat-safe up to 121°C), boiling water was hot enough to undo the deep drawing memory of the material, so the cups warped and shrunk!
Fortunately not enough deformation to pose a problem, but weird anyway. Should I do this more often, I'll invest into some stainless steel gear for sure.

Back to HP cooking: Once the “potato mash” phase has slowly turned into the “vaseline phase” (proper gel, saponification mostly finished), I combined the two batters (still lye-heavy at this time), and split them evenly across two (new) cups. Into one I added the saved PCSF, in the other the mastic, that I had previously dissolved/molten into some PCSF as well.
(More on mastic in a follow-up comment)

It didn't take long until the mass has turned in something similar to gel phase again. Some plop and glop later, I had it squeezed into a squarish column mould.

The other day, it was time to escalate the “M” silliness to the shape of the bars. Apart from some chipping from the HP soap (what's colloquially referred to as “rustic look”), cutting was straightforward. I cut out a broad triangle at the top, and two at the bottom, so that the bars got this self-explanatory shape. Not that I could confuse them with anything else – the macadamia oil once again has lent them some “bodily” colour.

From washing the tools after cutting, this soap does have quite some explosive lather! I can't wait to give them the rest they need now, and in a few weeks test if this has anything to do with the mastic, or it's “just” the laurics (from murumuru) + macadamia + mango butter, that is the new secret weapon in abundant, fluffy, thick and creamy suds.

More on mastic resin

Mastic is the resin of Pistacia lentiscus harvested on the Greek island of Chios.
As such, it contains free acids. I didn't want to add it early in the process to prevent early solidification/soap on a stick (cf. pine tar soap). Sources attribute oil solubility to it, so I shifted its application to the post-cook superfat (PCSF).
To make things more thorough, I found a SAP source for mastic, saying it has a K-SAP of 82-92: so I cut down 0.4 g of the oils for 1 g of mastic added.

There are few mentionings of mastic in soap: neither gave helpful usage rate numbers. So I guessed that 1.5%TOW would be a good starting point.

My mastic is in tear shape (see the drops in the incense brazier in the photo above), and I'm too lazy to grind it up. So I heated oils branched off from the batch oils, and threw in the tears. First not much happened, but around 100°C they started to soften, and rather quickly dissolve/melt into the oils 😀. At the same time, the melt started to give off dense, aromatic fumes! Gave me a wistful memory flash-back of the tiny, poorly lit Greek churches, where the light of the candles would make the gold mosaic glow, and you can hardly breathe in the fog banks of incense.

Anyway, immediately after adding that mastic mix to the soap batter, that odour disappeared. The soaps hardly smell different from each other. Yet, the mastic tears themselves don't smell either, so I should really judge this only after some serious amount of cure.
That's some good looking soap. I was going to compliment you on having HP soap fluid enough to mold well, but I see you didn't. You cut them beautifully though. I cannot cut soap evenly. Even with a cutter sometimes. I muck it up every time I try to slice with a knife. Can't wait to hear how it performs after the cure.
The wire cutter really helped to get the “faces” even. For the triangles, I've used a knife, and was surprised how well it worked.

ETA: HP pour-ability highly depends on moisture content. I had started with about 24% lye (or 45%TOW water), but it invariably lost quite some moisture during cooking, that I refused to replenish (“water” starts with “W” in German too 😉). Life probably would have been easier with a wetter post-cook gel. But the moral of the story is apparently that I didn't do it to make life easy.
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That is such a cool challenge! I am going to read the post again after I type this - I do enjoy reading your posts, always new things to learn for me.

Soap looks great too in my opinion :)

Edit: Are you going to do other letters too? Haha
I'm seriously impressed and in love the shape of your M soaps (I have a penchant for typefaces and fonts). Look at how beautiful they are! Chunky yet elegant with their rounded corners at the top.

Anyway 😁 thank you for documenting this! As a CP soaper I often wondered how HP is done, and I hadn't heard of mastic before so this was a good read.

Can I ask what does TOW stand for?
Thank you! Hehehe

Aren't you the elemi lady?
I am? I do use the essential oil quite often, and the carrier oil of the same fruit/tree (pili) in some formulations, but I have not yet touched the resin that I have. Guess I have to now, huh?
Yes! ;)
To be fair, I only read about elemi resin a few days ago, that it's not only the stuff where the EO is distilled from, but valuable by itself. No idea if anything of it keeps up in soap – it's forgivable to start with better-known resins.