At last my organic chem classes are useful
Hi,
I am new to the forum and I am not sure what WSSB is. If it is an oil supplier, could you give me the expanded name as I would like to find a cheaper source for coconut oils.
As far as the question as to why your palm oil is liquid versus a solid has to do with its fatty acid profile. I have bought Indonesian palm oil that was a semi-solid as was mentioned by spots71 in the thread. I have also used a hydrogenated palm oil shortening which was solid at room temp.
Palm oil is not a pure chemical, it is a mixture of different tri (and di and mono)glycerides which are composed of fatty acids.with palmitic and oleic acids being the largest amounts by percentage. Palmitic acid has a melting point of approx 64 deg C (147 deg F). Oleic acid has a MP of 14 deg C (57 deg F). The melting point of the palm oil you received is determined by the proportions of the fatty acids that make up the mixture, the length of the FA carbon chains and whether they are saturated or not. Unsaturated fatty acids have lower MP than saturated FA.
Palmitic acid is a saturated fat while oleic acid is a mono-unsaturated fat. So I can speculate that the palm oil you received has a higher percentage of oleic acid, enough to lower the MP to below room temp.
When veggie oils are made, it's not just some guy in a Sinchan t-shirt smoking a cig, running a cold-press. A series of complex steps refines the oil into the product you get. A very precise process called fractionation separates out fatty acids according to carbon chain lengths and the manufacturer can control the purity and types of fatty acids that go into the mix according what the product is being used for. There is a demand for unsaturated cooking oil these days and I can also speculate that your palm oil was highly refined according to that profile. My Indonesian palm oil was not as refined as it probably contained more palmitic acid.
Wait.....wait......waaaiiiiittt! Come back....we're finally getting to the good part! There will be no livin' with ya once you get going here, ya big soap nerd! Um...I mean Soap Wizard!
This then begs a question...if palm oil (and by extension other oils) is a mix of triglycerides made up of a mix of fatty acids, how does that mix affect my soap?
Well, saturated fatty acids make a harder bar while unsaturated FA's tend to make a softer bar. Easy, right? That's partly why lard, which is composed of a mix of more highly saturated fatty acids makes a hard bar while olive oil makes a softer bar.
Because each oil is a mix of fatty acids, it gets complicated trying to determine the effects a particular oil has on a soap product.
Fer instance, we know that coconut oil has good cleansing and lather properties...and looking at it's fatty acid profile on soapcalc shows that it has a large amount of lauric acid, which is a short chain saturated FA. The shorter the chain the more the polar carboxyl end of the FA dominates increasing the solubility of the soap in water, producing a fast foaming, large bubbly lather.
The longer the nonpolar carbon chain is the more it dominates and tends to get absorbed into the skin (cell membranes are lipid bilayers...remember that from high school?) so they are less soluble in water but they also don't strip the oil from your skin as quickly. Lard is a mix of oleic, palmitic and stearic acids which are 18 and 16 carbon chain FAs so they are less soluble in water, producing a small-bubbled stable lather. However, oleic acid is unsaturated which increases lard's relative solubility so it does still produce lather. Pure stearic acid is used to make crayons and would probably produce a very hard soap bar with almost no lather.
See how cool this is? By varying the oils you use according to their FA carbon chain length and saturation, you make soaps that are silky, or bubbly or strong or conditioning or hard or soft and be able to do it consistently. This provides a person with great soap bases upon which to explore the art and magic of soap crafting.
I realize this was a rather long explanation but I am learning to enjoy the technical aspects of soapmaking as much as I enjoy getting the color swirls to come out right. If I can get a handle now on mixing up foo-foo (EO/FO), I'll be set.
