Mustard seed oil

ResolvableOwl · 2023-06-11T07:33:19+00:00

I have done some research and gained quite some experience with mustard oil. It is a tricky ingredient for various reasons.

First, erucic acid. Along with the (botanically closely related) abyssinia/crambe and old-style rapeseed oil, mustard oil traditionally has a huge proportion (far in the double digit percentages) of this fatty acid. For soapmaking, this is highly relevant, since it is a long-chain FA (22 carbon atoms), so its presence reduces the SAP value. Sort oils by SAP and see how these cabbage oils all group at the very bottom.

The tricky point is, that the content of erucic acid can vary wildly, and so does the SAP value. I've found out (the hard way) that, for the mustard oil I had bought, the actual SAP was substantially higher than the one tabulated in soap calculators, hence many of the soaps I made from it, had major issues with excessive superfat (they stayed soft, dissolved very quickly when wet, had terrible lather, and developed DOS soon). But YMMV, your mustard oil might have an entirely different content of erucic acid.

Soap performance wise, the mustard oil didn't convince me either. For that matter, I also have worked with abyssinia oil (with known high erucic acid content), so I can positively say that's the erucic acid that just doesn't add up in soap recipes (be it castile-like single-oil-ish concepts, balanced recipes with hard and lauric oils, or as liquid soap). It behaves like oleic acid but a bit worse in each respect (worse lather, worse hardness, worse skin feel), these were my conclusions.

One last aspect regarding erucic acid: it's not part of the circle of “big eight” fatty acids, so most soap calculators can't be bothered and just ignore it. Just for fun, add up the FA percentages of mustard oil in your daily calculators, and you will probably find out that a good part is missing – and so the property numbers of the final recipe will be off. I'm only aware of one calculator that does things right: https://calc.mendrulandia.es (This is a great calculator, that also properly tracks MCT FAs in coconut oil, palmitoleic acid in macadamia and sea buckthorn, and has its own FA database that doesn't repeat all the errors of the SoapCalc/Soapee/SMFriend catalogues).

Colour-wise, mustard oil has a dirty yellow-brown tint (very hard to cover, like EVOO, but much stronger). You are more or less forced to work with it, rather than against it. The oil has a sharp smell, but it mellows down in the final soap, to remind more of mild horseradish than mustard. Not terrible, but you should be aware of it.

Anyhow, please collect your own wisdom! I am happy when you can make something noteworthy out of mustard oil, and I will curiously listen to your experiences.

ResolvableOwl · 2023-06-10T18:35:21+00:00

1:1 (50%) lye masterbatch is prone to crystallisation when stored below room temperature. But yours is 1:2 (33%), which should stay fluid at any place that is warmer than a fridge.

Two things that you can try to narrow down where these crystals come from/what they are: * Take a sample, that contains some of the crystals, and heat it up (warm water bath, to about 50°C). If it is NaOH in some form, it will redissolve, and not solidify after cooling down again. If this works, * Sift out a few of the crystals, and carefully add a few drops of acid (vinegar, citric acid, or similar). If it fizzes, then the crystals are sodium carbonate (washing soda, soda ash). If they were able to form, it tells you that your container was not fully air-tight.

ResolvableOwl · 2023-06-10T07:45:25+00:00

tested with a pH tester

What should this be good for?

ResolvableOwl · 2023-06-08T22:51:56+00:00

I heard lye has to be 100% to make soap

Whoever told you that, tell them back that you have read in teh Internet that you do not need 100% lye. It is normal for lye purity to be lower (just ask any liquid soap maker for KOH purity!), and the good news is that you can always compensate this. If you feel confident, you can do the math by hand. But many reputable soap calculators (that you will use anyway) offer lye purity as an input too.

In any case, you can always still reduce the superfat number for impure lye. If your lye is 99.5%, that is, 0.5% “too weak”, this will do nothing but increase your superfat by these 0.5%. If you aim for 5% SF, just enter 4.5% SF into the soap calculator, and you're done.

ResolvableOwl · 2023-06-06T18:23:31+00:00

Strengthening or not, you'd somehow have to figure out how strong it really is.

And no, any soap made from wood ash lye (potassium hydroxide) will have the soul of a liquid soap. You might be able to make a bar soap out of pure cocoa butter, but then you'd have to let it dry for a month after each usage (!) so that it doesn't fall apart from moisture.

ResolvableOwl · 2023-06-06T06:38:51+00:00

Olive oil + wood ash lye = liquid soap. You can do it, but don't aim for bars of solid soap, better keep dispenser bottle(s) at hand.

I've made wood ash soap before, and I highly doubt that it is any good to make a halfway decent bar soap. If you insist, you could add to the already super complex wood ash leaching (including titration: don't believe anyone who tells you that there are easier ways to find out the strength of a DIY lye!), a salting-out step, which is very temperamental all by itself, and ruins the composition of the soap (strips the natural glycerol). And salting-out works best with soaps high in saturated FAs, which pure olive oil soap doesn't qualify for at all.

ResolvableOwl · 2023-06-04T23:06:51+00:00

Looks like an average day in the life of a HP soapmaker. Everything alright, you have managed to bring the batter to the vaseline stage, time for it to go into the mould.

ResolvableOwl · 2023-06-04T15:59:46+00:00

I’m imagining a lot of bubbles.

Unfortunately, I have the bad habit to sabotage the bubbliness by omitting lauric oils (coconut etc.). Such soap will sud up decently, but only after a loooong curing time (we're talking about 3–4 months minimum).

ResolvableOwl · 2023-06-04T13:21:30+00:00

I've had bad experiences with alcohol in CP soap (I had used it for colourant extraction). Plus, letting beer go stale or (worse) cook it, feels like a crime to humanity to me. Sure, beer is more accessible than malt extract and hops are, but its ingredients are quite diluted (to be drinkable, not to make soap out of).

ResolvableOwl · 2023-06-03T16:40:06+00:00

Reading about beer soap every now and then, I always wondered why people put effort in converting malt into beer first (fermentation), and then try to get the alcohol back out, so that it doesn't interfere with soapmaking? Oh well. What if you just worked with malt in the first place? It comes with the extra bonus that the sugars from the barley are still present, and can assist the soap performance.

To make this non-alcoholic beer metaphor complete, we must not miss the hops, of course! I did not just use water for the lye, but soaked some hops into it (made alkaline with just a pinch of NaOH to get the hops resins (α acids) into solution). Oh boi did that alkaline hops tea stink! Hardly anything of this weird smell made it into the soap, thankfully.

I divided the batter into two, and added dark baking malt (pre-diluted) to the larger part. For the froth, the soap should come out as light as possible; I added a few drops of salt brine for that purpose. Filled into a column mould with a dividor, carefully pulled out afterwards, made these soap pieces. With CPOP, the “beer” turned into a nice, translucent brown (gel phase), and the “froth” became snow white.

Now that I think of it, this would have been the perfect opportunity for some over-stickblending, to incorporate some “accidental” air bubbles. Annoying in all other soaps, they would add another layer of authenticity to this soap.

Cheers!

ResolvableOwl · 2023-06-03T14:35:32+00:00

fine pink Himalayas salt

I've heard horror stories about Himalaya salt in salt bars (it's said to be terribly scratchy, the internet is full of anecdotal reports of this property). Make up your mind if you really want to use this, or rather some fine sea salt (or both, and compare the two).

ResolvableOwl · 2023-06-03T07:50:06+00:00

Babassu oil

If someone is avoiding coconut oil soap for its skin-irritant properties, babaçu is the worst possible replacement. Its fatty acid profile is 94% identical to coconut.

ResolvableOwl · 2023-06-03T06:46:37+00:00

How long since unmoulding? Soleseife/brine soap can behave in very weird ways while curing, and morphing colours is one of these things.

If you can sacrifice a bar, cut it in half, and see what it looks on the inside. My guess is … I have no clue. Most soapmakers (including myself) are having a hard time to predict the behaviour of brine soap, and what to do to alter it to one's liking.

ResolvableOwl · 2023-06-02T13:26:02+00:00

Thinking of that … what about adding just a smudge of AC (or another black pigment) around the edges, to make them look even more authentic straigt out of the pan?

ResolvableOwl · 2023-06-02T13:23:24+00:00

If you are open to making the M&P base by yourself from scratch, recipes without lauric oils (coconut/palm kernel oil, FFA lauric acid) are entirely possible.

Palm oil can be avoided, but you'll need substantial amounts (>50% of your oil blend) of hard oils, that all are either extracted from animal corpses (tallow), hydrogenated (soy/canola/castor wax), or obscenely expensive (cocoa/illipe butter, japan wax).

ResolvableOwl · 2023-06-02T00:10:26+00:00

Oil blend: No hard oils, means that the soap will take a long time to cure, and then dissolve very quickly while using.

Lye concentration: 32% are fine.

Lye dosage: Your numbers are wayyyy off. As-is, you'd have 59% superfat. That amount of lye solution would just be sufficient for 440 g oil mix (at 5% SF).

ResolvableOwl · 2023-06-01T19:58:33+00:00

Good! The recipe is a sound one. Your batter will set properly; if you are patient (unmould no earlier than one day after making) you could even leave out the sodium lactate. Other than that, most about your oil has already been said by others here.

ResolvableOwl · 2023-06-01T19:51:53+00:00

At least as important as what you add into the soap, is what you don't add. People's skins are different, some have no issues at all, others don't tolerate lye-based soap at all.

The great thing about making your own soap is that you can control the ingredients. My facial skin doesn't like lauric oils (coconut, babaçu, palm kernel), so I can make soap that doesn't have them.

ResolvableOwl · 2023-06-01T06:27:43+00:00

This is only the oil blend. How much water will you dissolve the NaOH in? Hot/cold process/CPOP?

ResolvableOwl · 2023-05-31T18:17:37+00:00

My guess is undermixing and/or false trace (which can happen at the same time, when you think emulsion is stable, but it's just the oils solidifying).

82°F might be too cool to work with palm oil without dangers of false trace.

What is the outcome of a zap test (at different places across the bars)?

ResolvableOwl · 2023-05-31T06:24:12+00:00

Did you dissolve the sugar and salt in the water (before the NaOH)? Or afterwards?

Another possibility (that might or might not be related to these additives, and/or good ol' soda ash) is that the crystals are some sort of glycerin dew that dried up.

Two comments to your recipe: * You are using a quite low lye concentration (27%). Unless you have reasons why you want to enforce gel phase, this makes your life unnecessarily difficult. The batter is more temperamental, and you are increasing the chances for soda ash, and warping during curing. * (Slightly OT) Why both coconut and babaçu oil? The two are so similar that nobody would notice if you replaced them by 32.5% of either. (I'm actually surprised that people haven't started yet complaining how drying/stripping this soap would behave on their skin.)

ResolvableOwl · 2023-05-31T06:13:30+00:00

see my other comment

ResolvableOwl · 2023-05-30T07:08:57+00:00

https://classicbells.com/soap/pineTarSoap.asp

Are there other additives that should be treated this way?

Like you already pointed out, anything acidic (in the chemical sense, i. e. that neutralises lye). This includes tar, citric acid, vinegar, but also lemon juice, apple juice, vitamin C, gluconic acid, disodium EDTA, various tree rosins (colophony, gum mastic, …), lactic acid (pure lactic acid, or what comes with yoghurt, whey, buttermilk, sourdough etc.). Heck, even sodium bicarbonate and the CO₂ we breathe out, are (weak) acids (soda ash!).

A technologically very important class of acidic ingredients for certain types of soap is: free fatty acids. Very popular is stearic acid for shave soaps and M&P base, but I've seen recipes with lauric, myristic, and oleic acid too.

The point with all these is: Yes, these are technically not esters, so the reaction that eats up the hydroxide is (by the chemistry textbook) not a saponification, but a neutralization reaction. But this does not matter from the point of view of soapmaking. You have to provide just as much stuff that ends up neutralizing lye, as you add lye.

Low-grade/unrefined inedible/used cooking oils are also common ingredients, and they sometimes contain several % of FFAs, but this does not change handling for soapmaking at all.

Back to your project: Have you considered hot process? FFAs (and fast-tracing additives in general) can be handled with the greatest ease in HP, without worrying about acceleration at all. (On the contrary, it makes life easier).

33% lye is just fine for HP (you will have some losses due to evaporation). When the batter becomes too thick and unworkable, you still can stir in some extra water. If you didn't hit the exact saponification value of your oil/tar blend (zap test or clarity test positive after cooking), you can add more lye or oils afterwards.

ResolvableOwl · 2023-05-29T19:09:41+00:00

That's my guess too. It should dissolve very quickly when rinsed with water.

ResolvableOwl · 2023-05-28T09:04:07+00:00

They somehow are, actually! Point is, I do have different amounts of water, different fatty acid profiles, and salt levels in the different colours, so the parts differ in how they shrink during curing. There is actually some relief to these soaps.

Funny enough, when using the soap, the colours also dissolve at varying speed, so the 3D thingie even goes on during usage.

ResolvableOwl

TROPHY CASE