Ode to Castor oil

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ResolvableOwl

Notorious Lyear
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Let's have a place where we can share our excitement over the miraculous properties of Ricinus alias castor oil!
  • From which other oil can you say that a few % make all of a difference? Its “lather boost” ability is legendary. Oddly enough, pure castor soaps don't perform well.
  • It makes a solid second place in Soapee's “Social Statistics” (66% of all recipes). In Modern Soapmaking's recipe survey, whopping 83% of recipes include it.
  • Castor is reported to help with scent retention when mixed with EOs/FOs ahead of time.
  • It readily gives perfectly clear liquid soap, that is also most resistant to superfat separation.
  • Castor oil comes from the ricinus plant (to be more precise, from its bean-shaped seeds – sorry @Zing), that happens to hold ricin, one of the most deadly poisons known at all. By the way, the German word for the castor plant is „Wunderbaum“ (literally: wonder tree; originally a biblical reference, I think this name is just as appropriate in a secular context). More weird naming fun: Ixodes ricinus is a tick that is a widespread bloodsucker in Europe. When engorged, it looks like a castor bean; experts are at odds if the tick was named after the bean, or the other way round.
  • Some physical peculiarities: Castor is the only oil that is fully miscible with alcohol (pure ethanol). When adding water, it precipitates as a milky goo. It is both the most viscous liquid oil (at room temperature), and the one with the highest density. All due to the presence of (chemically bound) ricinoleic acid, which is peculiar to castor oil, and unique in its hydroxyl group attached to the carbon chain. Polyglycerol polyricinoleate is a potent W/O emulsifier that has gained quite some attraction in chocolate production in the last years.
  • Many valuable oils originate from strictly tropical plants (palms, cocoa and karité trees…), but castor is happy with Mediterranean climate as well, and with proper precautions, can be cultivated in temperate latitudes too.
An autobiographical note: castor oil is to blame for pulling me into soapmaking! I saw bottles of it at a local Asian store (sold as massage oil), and some instinct inside me decided that now was the moment to become serious about soapmaking. Bought that bottle, went home, and started research on fatty acid profiles. Ever since, I only formulated very few batches without it, and the results were unambiguous. A wonder tree!
 
Thank you! Major castor oil fan here and good to know all those fun facts! Early in my soapmaking I heard about castor oil. I could not find it at my grocery store so I went to the drugstore and still couldn't find it. I asked the pharmacist who said look in the Hispanic section or laxative section. Wth?! I found several teeny tiny bottles in the Hispanic section and bought all of them. It was a game changer for me and has been in every recipe ever since.
 
I love using a tiny bit of castor oil in my face wash, too, along with PS80, some other skin-loving oils, and a few drops of lavender EO to improve the smell. I'd use a higher percentage of castor except that for me, it promotes hair growth in a very dramatic way. In other words, it is great on the scalp, not so much on the chin or upper lip. Not everyone reacts to castor that way, but I sure do!
 
SHUT THE FRONT DOOR!! WHAT??!! Castor oil grows hair?? I hardly have hair anymore (I call it "low maintenance" and I blame both my parents' genes and my children). All this time I could have been pouring it on my head??!!
Like I said, it doesn't have that affect on everyone. But you can read plenty of mommy blogs that tout it as:
~ an eyelash growth serum (kinda works for me, but I end up with one REALLY long lash so it looks quite odd),
~ eyebrow growth serum (no affect for me), and
~ scalp hair regrowth serum (works mildly well for me in that regard).

You can also add EOs that are known or believed to enhance hair growth - I believe your beloved Rosemary is one of them. ;) But results not guaranteed, YMMV, (insert all the usual legal disclaimers here).

EDIT: PS, I believe the correct application is rubbing/massaging, not pouring 😂
 
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Thanks @ResolvableOwl for the post. I too like castor oil, but at no more than 5%. I find I don't like the feel of soap at more than 5%. I add a little honey as well to most of my soaps, and that helps with bubbles as well. And it's just fun to tell people that there is honey in their soap.

How much honey do you add per pound of oils?
 
The great thing about Nature is that it is there for everyone, regardless if one invests into a scientific background, or just loves bubbly lather. The nature of castor oil in particular, but much more general, everything that happens around us.

Nature doesn't care if we understand it, and with the overwhelming gaps in the scientific narrative of the world in mind, that claim would be presumptuous anyway. We understand tiny aspects of it, but that's like a baker who understands how to make a decent dough, but still is lightyears away from the wheat plant how to grow the grains in the first place.
 
Reading that sentence again, it seems it is less a chemical, but a linguistic issue 🙄

Castor oil molecules hold loads of ricinoleic acid. This particular fatty acid is hardly found anywhere else in the plant kingdom.

Ordinary fatty acids have a carboxylic acid “head” (-COOH, -COO⁻, or -COO-R), that makes their alkali salts (soap) water-soluble.

The rest of the molecule is a hydrocarbon “tail”, that hates water, but binds to dirt, grease etc., and is the reason for soap to be useful for washing. This tail is called saturated in its most boring form (straight carbon chain), and unsaturated if it contains one or a few double bonds between carbon atoms. But that's about it for the most common FAs, that make up >95% of most oils in soapmaking, cooking, oil paint/varnish…

Enter castor oil. Ricinoleic acid is special, since it has something unique attached to its tail: a hydroxyl group (-OH, like alcohols), another attack point for polar environments to do weird stuff. Everything else being like ordinary oleic acid, it is an observation that this OH group makes it behave so differently from “boring” FAs in many ways.

It is a rare blessing that the castor plant had “decided” to invest so heavily into ricinoleic acid. It could be as well just have a few % of it, as so often with interesting and unusual FAs. But no, the wonder tree indulges us with nearly pure ricinoleic triglyceride!
 
I just started experimenting with Sorbitol which "supposedly" has a better lathering characteristics versus natural sugars. It is naturally occurring in some plants but it is a sugar alcohol rather than a glucose or fructose, etc.

To me it made more sense to dissolve the Sorbitol in the liquid rather than the oils.
 
Let's have a place where we can share our excitement over the miraculous properties of Ricinus alias castor oil!
  • From which other oil can you say that a few % make all of a difference? Its “lather boost” ability is legendary. Oddly enough, pure castor soaps don't perform well.
  • It makes a solid second place in Soapee's “Social Statistics” (66% of all recipes). In Modern Soapmaking's recipe survey, whopping 83% of recipes include it.
  • Castor is reported to help with scent retention when mixed with EOs/FOs ahead of time.
  • It readily gives perfectly clear liquid soap, that is also most resistant to superfat separation.
  • Castor oil comes from the ricinus plant (to be more precise, from its bean-shaped seeds – sorry @Zing), that happens to hold ricin, one of the most deadly poisons known at all. By the way, the German word for the castor plant is „Wunderbaum“ (literally: wonder tree; originally a biblical reference, I think this name is just as appropriate in a secular context). More weird naming fun: Ixodes ricinus is a tick that is a widespread bloodsucker in Europe. When engorged, it looks like a castor bean; experts are at odds if the tick was named after the bean, or the other way round.
  • Some physical peculiarities: Castor is the only oil that is fully miscible with alcohol (pure ethanol). When adding water, it precipitates as a milky goo. It is both the most viscous liquid oil (at room temperature), and the one with the highest density. All due to the presence of (chemically bound) ricinoleic acid, which is peculiar to castor oil, and unique in its hydroxyl group attached to the carbon chain. Polyglycerol polyricinoleate is a potent W/O emulsifier that has gained quite some attraction in chocolate production in the last years.
  • Many valuable oils originate from strictly tropical plants (palms, cocoa and karité trees…), but castor is happy with Mediterranean climate as well, and with proper precautions, can be cultivated in temperate latitudes too.
An autobiographical note: castor oil is to blame for pulling me into soapmaking! I saw bottles of it at a local Asian store (sold as massage oil), and some instinct inside me decided that now was the moment to become serious about soapmaking. Bought that bottle, went home, and started research on fatty acid profiles. Ever since, I only formulated very few batches without it, and the results were unambiguous. A wonder tree!
I LOVE castor oil as well! I’m going to say this and probably get beat up but...... I use 10% n all my soaps. There, I said it. There is another really cool thing about castor oil besides soap, scalp treatments, (yes, it makes your scalp so clean that your hair is so bouncy and clean!) Edgar Caycee had a protocol for liver treatment packs made with castor oil. Castor oil is a wonder oil!
 
I love using a tiny bit of castor oil in my face wash, too, along with PS80, some other skin-loving oils, and a few drops of lavender EO to improve the smell. I'd use a higher percentage of castor except that for me, it promotes hair growth in a very dramatic way. In other words, it is great on the scalp, not so much on the chin or upper lip. Not everyone reacts to castor that way, but I sure do!
Wow, really? I've been planning an oil for my dry & irritable scalp, maybe w/ some CBD for migraines. Now I'm extra glad I've got castor on hand! I do love it for soap, too. My mother is Team Moar Bubbles but still wants it to be super gentle & mild. 🤦🏻‍♀️
 
I love castor. Lovelovelovelove it. (lovelovelovelove..love)
I have it in all my soaps at 5 or 6%.

I can`t recall what the website was called, I bookmarked it many years ago, but one day it was just vanished.
I think it was America based, it had a ton of great recipes for lipbalms, creams and soaps etc. I only saved one recipe unfortunately, it was with castor. Brace yourselves it is a complex one: 95% castor and 5% beeswax.

It was an un-petroleum jelly (a nun petroleum jelly? 🙃)

I added mica and made lipgloss out of it. I still have some left over (to test how it fares. It is 4 years old now, but still doesn`t smell funny.)
I may have a problem, keeping things around to just smell when they turn...🙄
 
SHUT THE FRONT DOOR!! WHAT??!! Castor oil grows hair?? I hardly have hair anymore (I call it "low maintenance" and I blame both my parents' genes and my children). All this time I could have been pouring it on my head??!!

Well, some people claim that. But a pharmacist explained to me that it just makes the hair shaft thicker due to the humectant qualities of castor oil, but that there no proven science behind it. It would be difficult to study due to the many variances involved with hair growth such as it’s growth and shedding stages….which can change on a dime due to stress, hormones and diet, so any results would still be inconclusive.
 
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