Natural Colorants in Soap

I was inspired by my quasi-successful rebatch this week and decided to try making some more cold process soap. I had planned to do an olive oil and coconut oil soap, but we were low on the olive oil so I opted for a lard and coconut oil soap instead. I decided to follow a premade recipe, since my last attempt at making my own recipe was a disaster, and found one here. I want to use both coconut oil and lard becauseĀ coconut oil is a bit of a harsh cleaner but it also makes nice bubbles, while lard is a gentler cleaner that doesn’t make much bubbles at all. Most good soaps are made with multiple oils, and often more than two. Some people make 100% coconut oil soaps and then superfat them to make up for the harsh cleaning, but I think it would be better to try to make a soap that doesn’t strip away that base layer of natural oils in the first place, rather than one that strips them off and then replaces them with coconut oil.

Anyway I’m also really interested in finding natural ways to color my soap. It’s considered tricky unless you count lab-made mica as natural. Many plants don’t stay the same color after reacting with lye, and while you can find huge lists of natural soap colorants online, it’s pretty doubtful that their authors have actually made all these soaps to verify that their methods will work. Even if you can find tutorials with photos, they’re typically photos of freshly-made soap so it’s hard to say what it will actually look like once the soap is cured. A lot of soapmakers are pretty poo-poo on using natural colorants in their soap, many because they’ve been burned in the past by a bad experience. Coffee soap, though, is a tried and tested recipe, and I happened to have everything I needed to make coffee soap, so I decided to start there.

I’m not going to write a full tutorial on how to make cold process soap, because smarter people than me have already done such a good job, and also if I explain it wrong there’s a chance someone could hurt themselves. Soapmaking isn’t dangerous as long as you’re careful with your lye and your measuring, but you do need to know what you’re doing and use a bit of caution. The first time I made soap I was following this recipe but I ended up not liking the soap, so maybe that’s not the tutorial you want to follow. This book is $3 and I think it’s quite good.

To make simple coffee soap, all you have to do is take any cold process soap recipe and replace the lye water with double-strength coffee. Brewing it double-strength should help to get a more intense color. It can be old coffee and can be brewed with old grounds or coffee that you don’t like the smell/flavor of. None of that matters because none of the smell will make it into the final result, only the color. If you want your coffee soap to smell like coffee, you probably have to use a coffee-scented fragrance oil, preferably one designed for soap. I didn’t have that and I’m not really sure I want my soap to smell like coffee anyway, so I used some plum fragrance oil as well as a lavender+citrus+rosemary essential oil that I already had.

If I had one of those big slab molds, I probably would have made two batches of soap at the same time, one with coffee and one with plain water, which allows you to make some nifty designs. Alas I have no such mold, and barely enough to mold up the 2lb of soap that a single batch of this recipe would make, so I didn’t. (Halving/doubling recipes can be problematic in soapmaking so I’d rather just not go there right now.)

Soap rebatch, and why the heck?

Not entirely wrong.

This week I rebatched the first batch of soap I ever made, which was a 100% Castile soap recipe. I haven’t done much soapmaking and this had been my most successful batch yet, but it went completely unused and unloved because:

  • The soap was a bit rough on the hands. I don’t think it was technically lye-heavy, but it wasn’t superfatted at all and it made my hands feel itchy and dry after I used it.
  • It didn’t bubble. I didn’t understand what I was signing up for by making 100% olive oil soap. Castile soap doesn’t really bubble without extra additives, it just feels slimy.
  • I had added fragrance oil when I made it, but it had burned off during saponification, so there was no fragrance in the finished bars.
  • I had poured the original soap into some silicone candy molds, which were pretty but only served to accentuate the hard edges of my hard soap. Ouch.

So I grated it back down and rebatched it, which involved melting it in the slow cooker and adding heavy cream, coconut oil, and more fragrance oil. Rebatching is a way to fix many different problems with soap, but it never really ends up looking as smooth as the original soap. In my case I don’t mind, since this soap is for me, partially as a learning exercise and partially for home use, and I certainly want a soap that feels nice on the skin over a soap that looks good.

Why even make my own soap at all? In my area, even the “locally-made artisan soap” contains palm oil, which involves supporting slash-and-burn agriculture in the tropics, and I’m just not down with that. Nearly every brightly-colored soap also contains mica, which poses its own set of health and environmental concerns. I’m sure there are some issues with my soap as well, but at least I have a path forward to eliminate those issues as I find them. My next batch will likely be an OO+coconut oil soap, but eventually I’d like to find a recipe that works with more local ingredients. Coconuts don’t really grow here and olives are a bit of a stretch, although there is at least one grove in the Gulf Islands. Switching to local ingredients would likely mean switching to a recipe that uses more animal fats, possibly rendered pig lard, which I am OK with as long as the pig was raised and slaughtered in humane conditions. Lard is also supposed to make pretty good soap.

Another alternative in the PNW, especially for household cleaning, is the soapberry bush. I’d like one of these eventually but it’s probably a bit much to try to replace all my soap needs with it.

Anyway, I unmolded the first bar last night and I thought it was pretty funny because, as a rough rebatch soap, it didn’t fill the mold completely, so rather than being stamped with the words “100% HAND MADE” it says, “100% HAND MAD”, which isn’t an entirely-inaccurate way to describe some of my DIY motivations.

PS — tested out the soap. It feels good and it’ll clean ya!