These last two pressings to create an olive oil for making all natural soap, requires a solvent extraction process to extract the remaining oils from the residue or leftover parts of the first pressings. Pomace grade olive oil also uses the pits of the olives and is usually the best grade for soap making.
Each pressing of the olive does create an oil with a slightly different saponifiable value due to their fatty acid structure. For instance, the unsaponifiable percentage in pomace olive oil can create a faster tracing soap. Pomace grade may also create a slightly darker soap bar. So if you do decide to use the higher grades of olive oils, the trace time may be longer.
More benefits of olive oil in cold process soap making is in its gentleness on skin. For skin care, olive oil is a great moisturizer, providing a full moisturizing layer without clogging pores.
Yet, one of the non benefits of olive oil in cold process soap making is that it can create a bar with a limited lather, just as in 100% olive oil Castile soap. Yet, the olive oil-only bars are a mild and gentle cleanser. Also, the linoleic acid in the olive oil which creates a natural humectant. You can place olive oil directly on your skin, but this is a 'shiny' finish type of oil, meaning that it will not readily absorb and you will have a shininess to your skin. But it would certainly be perfect for a bath.
More good news with using olive oil for making all natural soap is the antioxidants, which can help to neutralize damaging free radicals that can lead to skin cancer and premature aging of the skin.
By itself, Olive Oil can be used as a shaving lubricant or to add after a shave. This oil is great for chapped lips and skin and can be used when making your own lip balm
(recipe and directions here).
Your hair can benefit from olive oil too. Benefits of olive oil in cold process soap making, is that these bars are reported to be the best type of shampoo bars. Consider using olive oil as a pre-shampoo moisturizer. Instead of buying one of those expensive hot oil hair treatments, knead a few tablespoons of olive oil onto warm wet hair, wrap up in a shower cap or towel for 30 minutes, then shampoo as usual.
There is also an extract from the plant - olive leaf extract, more here...
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