Castor oil is a thick, clear oil that helps increase the lather in soap - a rich, creamy lather. It's also a humectant (attracts moisture to your skin) oil. Just a little will do ... 5% - 8% in your recipe will work wonders. Shampoo bars often use 10% - 15% ... but more than that and you get a soft bar of soap. Castor oil has a fatty acid makeup that's completely unique - which makes what it contributes to your soap (the rich, creamy lather) unique.
Castor oil will speed up the rate at which your soap will get to trace - so I usually leave it out of recipes that require complex swirls or designs.
The Spruce
This thick and viscous liquid is extracted from the Castor Bean Plant and has a slight but distinctive smell. It behaves like a humectant, meaning it draws moisture from the air onto the skin. If you want a stable, lush lather, you can technically use Castor Oil in your recipe up to 25% (though using much more than 10% can make for a sticky soft bar). This oil is great for superfatting and is often used to contribute to the thick and large bubbles in most bars. Most soapers use this oil in the range of 2-5% traditionally.
Soap Queen
Coconut oil is one of the primary oils soapmakers use in their soap. Susan Miller Cavitch, in her book The Soapmaker's Companion, calls it "a gift." Most of the coconut oil sold and used has a melting point of 76°, but there is a hydrogenated type that melts at 92°. Either version works the same to give tremendous, bubbly lather to your soap. It also makes for a very hard, white bar of soap. The collective opinion is that using more than 30% coconut oil in your recipe will be drying to the skin. Yes, the super-cleansing nature of coconut oil can strip oils from your skin, but I have often used it at 30%-40% with great results, especially with a slightly higher (6-8%) superfat. Or, you can make 100% coconut oil soap with a 20% superfat. It's an amazing bar of soap.
The Spruce
One of the most common raw materials used in the soap and cosmetic industry, Coconut Oil comes in a range of melting points (76°F and 92°F are the most common) and has one of the lowest melting points of any solid oil. Both the 76 and 92 degree melting point oils have the same saponification value and can both be used in your soapmaking recipes. Coconut oil is a super cleansing addition that produces big, copious bubbles. It is so good at its job that it can inadvertently strip skin of moisture (leaving it dry and even irritated). A usage rate of 25% is ideal for the perfect balance of cleansing without drying. For more sensitive skin, keep the Coconut Oil a 15% or less in your bar.
Soap Queen
Grapeseed oil is a lightweight, moisturizing oil that is a good additive to soap in small quantities. It doesn't have a long shelf life, so unless you treat it with rosemary oleoresin extract, or have a very low superfat percentage, don't use it more than about 5% in your recipe. Grapeseed oil is lovely in lotions, shaving oils, bath oils, and especially massage oils as it absorbs well without a really greasy afterfeeling.
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This lightweight yellowish-green oil makes for a great salt and sugar scrub ingredient and is full of antioxidants. Somewhat oilier than Sweet Almond Oil, Grapeseed adsorbs quickly and you are left with kissably soft and smooth skin. When working with cold process recipes, you can use it up to 15% of your total oils.
Soap Queen
Lard makes a super-hard, very white bar of soap with a low, creamy, stable lather that is, believe it or not, nicely moisturizing. Before vegetable oils were commonly available, it was one of the main fats (along with beef tallow) that folks used to make soap. If you use animal oils in your soap, then combining lard with some of the other liquid oils like coconut and olive makes a wonderful, well-balanced bar of soap - and is really economical. Make sure your lard is fresh and of high quality. Poor or spoiled lard can give a lardy/bacony/greasy scent to your soap. Use it at any percentage in your recipe, but we recommend not much more than 30-40% or so. Cold process laundry soap can be made with 100% lard with a 0% superfat percentage.
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Extra virgin and virgin olive oils come from the very first gentle pressing of the olives. The refined, or Grade A oil (generally the best grade for soap), comes from the second pressing and is lightly refined/filtered. 100% olive oil makes the famous "Castille soap" and "Marseille soap" must contain at least 72% olive oil. Olive oil is generally the #1 oil in most soap makers' recipes - and for good reason. Olive oil soaps are very moisturizing, make hard, white bars of soap (though high % olive oil soaps take a longer time to cure) and are exceptionally mild. But the lather from Castille soap is low and a bit slimy. Most soap makers combine olive oil with other oils to improve the lather.
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Used essentially in soap for its incredibly creamy and mild lather, Olive Oil yields a soap bar that will last longer with tiny bubbles. Any grade (Pomace, Pure or EVOO) can be used in soapmaking, but we have found that the Pure Olive Oil tends to trace much slower than the Pomace Olive Oil, so be sure to use the Pure Olive Oil if you are soaping with a recipe that you need time to work with. It is a wonderful addition to any soap recipe and can be used up to 100%.
Soap Queen
Palm oil, along with olive and coconut, is one of the top oils used by soap makers today. Because of the qualities, it gives soap, it is often called "veggie tallow" in that it gives many of the same qualities that beef tallow does - a hard bar with a rich creamy lather. Alone, it's pretty unremarkable, but combined with other oils like olive, coconut, and castor, it makes great, hard, long-lasting soap. There are some serious concerns about palm oil farming in Malaysia - and the impact it is having on both the land and the people. We know several soap makers who have eliminated palm oil from their recipes because of this.
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Palm Oil is widely used for it's hardening properties in soap, and acts as a secondary lathering agent when used in conjunction with Coconut Oil. This is a medium-weight oil that can be used up to 30% in any given cold process recipe. The Palm Oil for sale on Bramble Berry's website is purchased from a member of the the Roundtable on Sustainable Palm Oil (RSPO), an organization that supports sustainable palm oil production.
Soap Queen
Like lard, beef tallow gives you a super-hard, white bar of soap with low, creamy, stable lather that is very moisturizing. Before vegetable oils were commonly available, it was one of the main fats that folks used to make soap - and remains one of the most common oils in soap. (Check your label for "sodium tallowate" - that's beef tallow.) If you are o.k. using animal oils in your soap, then combining beef tallow with some of the other liquid oils like coconut & olive makes a wonderful, well-balanced bar of soap. There is just something about the heavy, rich creaminess of the lather that I haven't been able to replicate in non-tallow soaps. While you can use it at any percentage in your recipe, I wouldn't recommend much more than 40% or so.
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