Antioxidants, DOS and Rancidity

[n6561echo]

I am just starting my research on this issue, but I thought I'd share some thoughts and recent findings with you.
1. While vitamin E has been a staple of the cosmetic industry, extensive research into the antioxidant contents of seeds and berries, is producing very encouraging results.
2. Most of their studies suggest that a combination two antioxidants is more effective than one.
3. Data published in the Journal of Food Composition and Analysis found that "the total a-tocopherol content may not be the best indicator of vitamin E activity in vegetable oils, and that a-tocopherol equivalents, and its' ratio to PUFA (polyunsaturated fatty acids) is more meaningful."

As an example, they found that sunflower oil contained 33mg of a-tocopherol/100grams of oil, and olive oil contained only 13mg/100g of oil. However, the a-tocopherol equivalents to PUFA ratio was 0.4 for sunflower oil, and greater than 1 for olive oil.

So, until there is more information, it appears the best way to avoid the DOS, is to limit the amount of linoleic, and linolenic.

 

[Kcryss]

So, until there is more information, it appears the best way to avoid the DOS, is to limit the amount of linoleic, and linolenic.

I agree totally. Before I made my first batch of soap I came across the information posted here: https://classicbells.com/soap/soapCalcNumbers.asp

I've used that information diligently on every single batch I make.

 

[Dawni]

So, until there is more information, it appears the best way to avoid the DOS, is to limit the amount of linoleic, and linolenic.

Yes, although some of us have experimented with more and the results aren't what we expected.

For example I have a 70% RBO soap that's not showing signs of DOS on the 7th month. Waiting to see what happens in a year.

I also have a soap with more grapeseed oil than usually recommended, no sign of DOS at about a year (I think it's this month lol)

Whereas, my Castiles got DOS fairly early on.. All my soaps have the same conditions and environment while making n curing. Baffled me, this batch.

 

[Kcryss]

I'm guessing that vitamin E content in each type of oil may be the reason for either getting or not getting DOS. Here is one article on content of some oils, sadly, RBO isn't listed here: https://www.researchgate.net/figure/Vitamin-E-content-in-vegetable-oils_tbl1_262021918