Teach Soap

I saw this on the other soap forum, quote

"One of the easiest ways to have your soap go prematurely rancid is to overheat the oils, killing off the antioxidants that preserve the shelf life of the oils. It’s best to melt these delicate oils over a double boiler so you don’t overheat them."

Is this true? Now I have to do a little research about the heat sensitivity level of each oil...

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Shieh Design Studio
https://www.facebook.com/ShiehDesignStudio
http://soapandrestless.blogspot.com

That's one possible solution. Another is if your oils are getting close to an expiration date, or going rancid.

_________________
Irena
Closed minds are like faulty parachutes; they refuse to open.

_________________
Shieh Design Studio
https://www.facebook.com/ShiehDesignStudio
http://soapandrestless.blogspot.com

Blame the soap gremlins.

_________________
Irena
Closed minds are like faulty parachutes; they refuse to open.

_________________
Shieh Design Studio
https://www.facebook.com/ShiehDesignStudio
http://soapandrestless.blogspot.com

Never had that happen, what does it look like or does it smell??

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Four Seasons Fine Handcrafted Soaps
& Specialties, Inc.
Laugh, Love, Live!

_________________
Irena
Closed minds are like faulty parachutes; they refuse to open.

I'm still mystified by DOS too. I have made hundreds of batches and been soaping more than 3 years and still have not experienced DOS. I also have made some batches with "old" oils as an experiment to see what would happen. So far, it's all just the same soap. Go figure!

I occasionally see DOS when I have soap that has been sitting around for long periods of time (>6 or 8 months) and when I used too much "soft" oils in the recipe like canola oil. I didn't see any the first year I was making soap because I was giving it away, or selling as fast as I made it so I never had a chance to see the "older" soaps lying around. I eliminated the use of canola oil and haven't seen it in a while.

I don't think it's due to temperature because I get my oils & butters pretty hot (over 230 F) to melt the chuck of beeswax I put in. In other batches that don't have beeswax I only heat them to about 120. I just have a hard time believing it's due to temperature of the initial oil melting. Besides, it takes shea butter a temp of 185 F (or close to that) to temper. Sorry....just not buying the temperature argument. (Gosh....I love idioms)

I have bars from every batch I have ever made and I use canola and soy regularly. I don't buy the temp idea either.

_________________
Four Seasons Fine Handcrafted Soaps
& Specialties, Inc.
Laugh, Love, Live!

I'm gonna hijack this thread and ask about beeswax! I've used beeswax before but it was such a nuisance. Kept wanting to resolidify. If you get the oils that hot and then cool them down, doesn't the beeswax start to resolidfy? Just curious.

I can see how the change in the properties of the oils could cause the DOS, since both age, and heat can degrade and change the properties. And I just did a bit of research to find out at what temperatures the oils degrade at.

Most oils need a very very high temperature before they break down.
Beeswax melting point is 147 °F, which doesn't degrade it. However, the flash point would 400 °F.

Most other oils actually degrade at even higher temperatures than beeswax.
In cooking they call that point the "Smoking point" which is when the properties of the oils are changing. Which makes sense, cause if it's giving off fumes, then obviously something is leaving the oil.

I found this list of oils sorted by what temperature they start to degrade at.

So we can see canola oil degrades at a very low temperature compared to most or all oils. lol
I remember soapbuddy mentioning that she always got DOS with canola, but I think soapbuddy also uses beeswax in her recipes because if helps keep the ash down. (Am I right?)
So, that said, I can definitely see how that was a possibility, since the degrading point of canola, and the melting point of beeswax are so close together. 147 °F and 225°F. It's still a big gap, but heck, it's not hard to get it up there.

List sorted by temperatures at which the oils begin to degrade or smoke.

200's
225 F: Canola Oil, Unrefined
: Flaxseed Oil, Unrefined
: Safflower Oil, Unrefined
: Sunflower Oil, Unrefined
300's
320 F: Corn Oil, Unrefined
: High-Oleic Sunflower Oil,
Unrefined
: Olive Oil, Unrefined
: Peanut Oil, Unrefined
: Safflower Oil, Semi-Refined
: Soy Oil, Unrefined
: Walnut Oil, Unrefined

325 F: Shortening, Emulsified
Vegetable†

330 F: Hemp Seed Oil¥¥

350 F: Butter (Good Eats)
: Canola Oil, Semi-Refined
: Coconut Oil†
: Sesame Oil, Unrefined
: Soy Oil, Semi-Refined
356-370 F: Vegetable Shortening
361-401 F: Lard
375 F: Olive Oil (Good Eats)
389 F: Macadamia Nut Oil††
400's
400 F: Canola Oil, Refined
: Walnut Oil, Semi-Refined
406 F: Olive Oil, Extra Virgin*
410 F: Corn Oil (Good Eats)
: Sesame Oil**
420 F: Cottonseed Oil†
: Grapeseed Oil¥
: Olive Oil, Virgin**
430 F: Almond Oil***
: Hazelnut Oil***
435 F: Canola Oil (Good Eats)
438 F: Olive Oil*
: Rapeseed Oil***
440 F: Peanut Oil†
: Sunflower Oil†
450 F: Corn Oil, Refined
: High-Oleic Sunflower Oil,
Refined
: Peanut Oil, Refined
(Good Eats)
: Safflower Oil, Ref.
(Good Eats)
: Sesame Oil, Semi-Refined
: Soy Oil, Refined
: Sunflower Oil, Semi-Refined
460 F: Olive Pomace Oil**
468 F: Olive Oil, Extra Light*
485 F: Grapeseed Oil**
495 F: Soy Bean Oil†
500's
510 F: Safflower Oil†
520 F: Avocado Oil, Refined


Here's the list in Alpha


Almond Oil*** 430 F

Avocado Oil: Refined 520 F

Butter (Good Eats) 350 F

Canola Oil: Unrefined 225 F
Semi-Refined 350 F
Refined 400 F
(Good Eats) 435 F

Coconut Oil† 350 F

Corn Oil: Unrefined 320 F
(Good Eats) 410 F
Refined 450 F

Cottonseed Oil† 420 F

Flaxseed Oil, Unrefined 225 F

Hazelnut Oil*** 430 F

Hemp Seed Oil¥¥ 330 F

Grapeseed Oil¥ 420 F
Grapeseed Oil** 485 F

Lard 361-401 F

Macadamia Nut Oil†† 389 F

Olive Oil: Unrefined 320 F
(Good Eats) 375 F
Extra Virgin* 406 F
Virgin** 420 F
Olive Oil* 438 F
Pomace Oil** 460 F
Extra Light* 468 F

Peanut Oil: Unrefined 320 F
Peanut Oil† 440 F
Peanut Oil, Refined
(Good Eats) 450 F

Rapeseed Oil*** 438 F

Safflower Oil: Unrefined 225 F
Semi-Refined 320 F
Refined (Good Eats) 450 F

Safflower Oil† 510 F

Sesame Oil : Unrefined 350 F
Sesame Oil**: 410 F
Semi-Refined 450 F

Shortening, Emulsified
Vegetable† 325 F
Shortening, Vegetable 356-370 F

Soy Oil: Unrefined 320 F
Semi-Refined 350 F
Refined 450 F
Soy Oil† 495 F

Sunflower Oil†: 440 F
Unrefined 225 F
Semi-Refined 450 F

Walnut Oil, Unrefined 320 F
Semi-Refined 400 F
High-Oleic Sunflower Oil,
Unrefined 320 F
Refined 450 F

Great list kat393! Can I add this list to the newbie guide in this forum?

_________________
Irena
Closed minds are like faulty parachutes; they refuse to open.