Macadamia nuts contain a lot of vitamin E, but the oil does not as compared to other oils. It contains up to 122 ppm or 450 mg per kilogram of oil. It is cold pressed and the only Vitamin E found in it comes from the shells that might be pressed with it, but the refining of the oil eliminates most of it! Despite the low levels of Vitamin E, macadamia nut oil has high oxidative stability with a shelf life of up to 1 year. (I have seen it written that the oil can have up to 450 ppm, but recent studies show that although the nuts have a high level of Vitamin E, it doesn't translate to the oil.)
We find some nice phytosterols in this oil at 1613 mg per kilogram of oil, which is a nice amount. It is mostly made up from B-sitosterol (1506 mg per kilogram of oil) with some campesterol and stigmasterol making up the rest. These phytosterols behave like cortisone to reduce itchiness, redness, and irritated skin.
Macadamia nut oil contains catechins, which behave as free radical scavengers and anti-oxidants, and may act as anti-bacterial agents.
And it contains squalene - about 185 mg per kilogram of the oil - which can benefit chapped and cracked skin, help with cell regeneration, and may have some anti-bacterial properties.
Macadamia nut oil has a shelf life of about one year, and is a light to medium weight oil with a non-greasy feeling.
FORMULATING WITH MACADAMIA NUT OIL
You can use macadamia nut oil in any hair or body care product you like as a lightweight oil with a non-greasy feeling. It's a great substitute for some more expensive oils as well as a lovely addition to a moisturizing and softening lotion. Because it contains the palmitoleic acid found in sea buckthorn oil, try using it where you might use that oil in a facial serum or softening lotion. It's an inexpensive way of getting maximum palmitoleic acid in your products!
Because it resembles olive oil so well with similar levels of squalene and oleic acid, try it in a body or hair care product in place of olive oil.
And if you want a really moisturizing body butter with a little less greasiness, macadamia nut oil makes a great primary oil (along with a little IPM)!
When formulating with macadamia nut oil, I suggest adding Vitamin E to the mix, not so much for the anti-oxidant properties but for the softening properties. Most of the oils we use have high levels of Vitamin E, which offers softening and moisturizing properties, but macadamia nut oil is deficient in this area. So by adding it, we'll be replicating the lovely effects we get from those other oils while keeping the awesome qualities of macadamia nut oil.