canola and dos

[rszuba]

ok- i do have a couple of recipes where those bars end up with dos after time, question----how do i convert those to a non-canola recipe and still get the same great conditioning? my friends love my recipes(soaps) so i don't want there to be too much difference when i change the reicpe.

what oil is close to the same.... and is the dos and tea thing really true? maybe i'll just add tea.

thanks,
renee

 

[ChrissyB]

Whats the dos and tea thing?

You could sub the canola for olive, or sunflower is probably much more economical. But still conditioning.

 

[rszuba]

thanks,

i was reading about tea in your lye water helping to keep the dos at bay.

 

[ChrissyB]

I've never heard that.
I think you have to make a test batch with your normal recipe (with the canola) and the tea, and see how it goes.
Canola is notorious for DOS, I don't use it.
What percentage of canola are you currently using?
Other oils that are know DOS'ers are soy, corn, and probably a coupla others that I can't think of.

 

[topcat]

This is an interesting thread.....

I have only had two batches DOS on me. The only difference they had to my other soaps was they both had tallow and one also had canola....weird :?

Tanya

 

[kaseencook]

I use canola a lot, and DOS is an issue because there are a lot of unsaturated fats that easily break down via oxidation-reduction. Antioxidants are a way of reducing the oxidation of oils (and other things like cells and metals). Many food/drug manufacturers use antioxidants to help extend the shelf life of some cooking oils and supplements like primrose oil.

I have done some experiments on the use of natural antioxidant sources to stave off DOS in Canola soap. Using tea is a really good way of doing it do to the high amount of antioxidants as well as the fact that the tea completely spreads through the soap, where chunkier antioxidant sources are less easy to get every nook of soap covered (like cinnamon, cloves, ginger, nutmeg). Other good ones include oat flour, rosemary extract, vit E. Also the more fermented teas like oolong and celyon (black?) make the soap less brown than less fermented teas like green tea.

Also, the major source of radicals that start the oxidation process is from water that is broken down by UV from the sun (namely OH), so reducing the water content of the soap to a min (27% water as a % of oils works well) and keeping it out of the sun and in an airy, low humidity, place helps too.

But tea high in antioxidants (Ceylon, Green) has definitely staved off DOS in my canola soaps for 6 months and longer.

 

[ChrissyB]

I also believe that the freshness of your oils is a contributing factor.
If you use rancid oils, you are going to get rancid soap =DOS

Tanya, is it possible the the tallow you used in your soaps as already "off", or on it's way?
And Kaseen, that's very interesting. Makes perfect sense now you've explained it though!

 

[topcat]

I don't think the tallow was off or going that way Chrissy. I bought it from Coles the day before I used it in one batch and it smelled fine then? I am only going by smell though. I kept it in the fridge and used the rest in my whipped soap cupcakes with canola about a week later. Both batches DOS'd at around 4 1/2 to 5 months on.

Tanya

 

[ChrissyB]

Tanya, I have used tallow for soap cupcakes, and you're right, it doesn't have a smell.
It must have been the canola.
I haven't used it, I much prefer rice bran oil, but I know that "those in the know" don't like canola for dos reasons.

 

[donniej]

I bet that tea bagging tobacco in the oil will prevent anything from growing on the soap. using a small amount of titanium dioxide might help to prevent it as well, that is of course if you want a bright white soap...

I forget what metal they use in anti-bacterial soap but I know it's a metallic ion. Using that would surely work.

 

[kaseencook]

DOS isn't a bacterial issue though, it's the breaking of weak double bonds in unsaturated oils that turn into peroxides, the stinky yellow goop. Antioxidants are generally the only way to really stave off DOS under normal soap storage conditions.

Bacterial growth is generally not an issue with soap unless there are large patches of wet organic material on the outside of the soap, as soap is a salt of a fat and it is not a very good growth medium for bacteria and mould. Salts generally reduce the amount of water available for use by the bacterial cells (the water activity), and if there is no water most cells cannot survive unless they are adapted to extreme conditions. Perhaps under extreme conditions with bacteria that can handle low water availability, something could establish, but I think it is pretty rare. That's our theory anyway, my husband did his postgrad on the effect of water activity on the growth of e-coil for use in the meat industry (via the use of salts), I think it has some overlap with why soap does not grow large amounts bacteria.

These links have some good info about oil rancidity:

http://en.wikipedia.org/wiki/Rancidification

http://en.wikipedia.org/wiki/Lipid_peroxidation

 

[rszuba]

WoW, great info, thanks, i love the science behind some of this. sometimes i just need someone to explain it to me, rather than try and read the book.lol. hence, construction worker, hence soapmaker--- hands on learning is what i'm all about.

 

[kaseencook]

Yea, it is cool stuff! When I started soaping I had no idea that DOS would occur in soap with canola, and a got this huge surprise when my soap all turned orange and stinky! There was a lot of it that went to the land fill, several boxes..... although it would have been ok to use, it was so stinky The smell wafted out of the "soap room" and some of it was slimy.

Anyway, haven't had those issues since using natural antioxidants, I like to use oat flour mostly on the HP soap I keep for my self and testing moulds/stamps/other, it lasts many months (prob not as long a some teas, teas (oolong, ceylon, green) are the best for the longest lasting canola) and is nice and creamy - best of all the canola is cheap! $12 for 4L (about 1 gallon). Woo Hoo!

 

[xraygrl]

ROE (Rosemary Oleoresin Extract) is a good antioxidant. I know a lot of soapers use it in their base oils to stave off rancidity.

 

[rszuba]

does roe have a scent and if it does, does it effect the soap recipe- mixing with your scent or if you wanted unscented soap, per say.

 

[xraygrl]

No, there will be no scent from the ROE. You use a very small amount in the base oils. It's been quite some time, I don't remember how much atm though.

 

[rszuba]

thanks

 

[lunchlady2009]

Can you still use soap that has DOS?

I don't sell mine, I have a small batch that has it.

 

[kaseencook]

I've used soap that is DOS, nothing wrong with it, the yellow is just a form of peroxide. Sometimes the shower can enhance the odour though :shock: