Identifying DOS prone oils

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SoapSap

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Can I determine on SoapCalc which oils are going to be problematic in developing DOS. What values should I be watching?
 
I had never look for it in soapcalc but I know that canola, soya, even avocado is a year of shelf life so it may get DOS . Most people add Roe to the open bottles of oils which slow the oxidatation. I hope someone smarter than me will chimm in shortly :p
 
hemp is a bad one
and so is sunflower
and flax has a super short shelf life

i have not had that problem yet, but i have heard about those 3 from a number of people
 
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High Oleic Sunflower works just fine. Hemp has a short shelf life but I some hemp soap I made 2.5 years ago and it's still going strong. No DOS. The key is to use those oils in lower percentages. I wouldn't use more than 15%
 
I love HO sunflower! Walmart sells it by the gallon and it lasts me for forever. I add .1% vitamin E to it when I open and also keep it in the fridge just as a precaution, however. I just finished a bottle that I opened over a year ago and it was still fine. I use hemp in my shampoo bars at 5% to help lower the chances of DOS. So far there hasn't been any, but they don't sit around long lol. I keep my hemp in the freezer and squeeze out as much air as possible after I use it. I also add vitamin E to it. Avocado was mentioned, but I haven't noticed it causing DOS. I make a bar with 20% and haven't added any vitamin E to it and I've never had one of those bars go rancid.. Hopefully I didn't just jinx myself lol.
 
Here is a post from the Essential Soap facebook group, thanks to Liz Ardlady:


LizArdlady: Linolenics are probably the worst for DOS. Keep an eye on your IV (Iodine value) which you can find on soapcalc.
 
So, should the Linolenic numbers and iodine value be in the high or low number range?
 
Lower IV and less linolenic acid will make your soap less prone to DOS.

FYI SoapCalc calculates an overall IV for your whole recipe, and gives recommended safe ranges to keep you on the right track.
 
High Linolenic

I read somewhere that you can get in trouble with DOS if linolenic is higher than around 12%. So when I've been playing around with soap calc to create recipes I've been keeping it around 10-11%.

Some people have recipes with very high amounts of Rice bran oil which would give very high linolenic numbers and I'm wondering why they don't seem to be getting DOS with such high percentages.

June
 
I also keep my (Linoleic + Linolenic) under 16 and Iodine rating on SoapCalc within the recommended range. I think DOS may also be influenced by relative humidity in your area. Fingers crossed, I haven't experienced DOS yet.
 
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