Rosemary CO2 turning soap yellow.

[Louise Taylor]

Hello. I made a recipe that I have made a number of times but added 1 gram of Rosemary CO2 to 1 litre of oils. All looked perfectly as normal until the lye went in. This soap is normally cream turning whiter as it cures. This time the lye went in and the batter became yellow. It’s quite a nice mustard yellow. I can only think that it must be a reaction with the Rosemary extract.
Has anyone else had this happen?

 

[DeeAnna]

I'm assuming you are adding rosemary CO2 extract to function as an antioxidant in the fat?

The dosage I recommend for rosemary oleoresin extract (ROE) -- not necessarily the same as rosemary CO2 extract -- is 0.5 g per 1000 g of fat. That is half of what you used, assuming ROE and rosemary CO2 extract are comparable. Do not overdose with antioxidants -- you can actually accelerate oxidation if you do.

Rosemary CO2 extract is different than ROE, however. I've never used the CO2 extract nor have I studied its chemical composition, so I can't say how it should be used. Have you gotten the manufacturer technical data for rosemary CO2 extract and learned whether it's recommended as an antioxidant and what the suggested dosage is?

When I use fats treated with ROE, the soap batter can blush orange, but the batter returns to a normal color afterwards and the soap is not discolored.

 

[Louise Taylor]

Thanks for your reply DeeAnna.
Yes, I am using it as an antioxidant and it is sold as an antioxidant. Thank you for the dosage recommendation - this was my first time using it and I had seen that Kevin Dunn recommended 1 gram. If I can use less than I will go ahead.

I do have the technical documentation. There is a lot of detail in the certificate of analysis and safety data sheet. The information leaflet tells me that there are 12 - 16% antioxidative reference compounds. I am going to have a good look through all the documents and on the website to see if the dosage is recommended anywhere.

 

[DeeAnna]

"...I had seen that Kevin Dunn recommended 1 gram ..."

Yes, that is true, but Dunn also specified he used ROE. He didn't say he used the CO2 extract of rosemary. I would not assume the two are equivalent, based on what I know of other herbal CO2 extracts and how they compare to conventional extracts.

Dunn used ROE at the upper end of the dosage range I've found reported in the literature. Typical numbers range from 0.2 to 1.0 g ROE per 1000 g fat (0.02% to 0.1% ppo). His students ran tests for weeks, not years, so it's hard to say if the dosage Dunn used would work well over a longer time or not.

What I can say is I've been using ROE for, oh, about 5 years now at a dosage of 0.5 g ROE per 1000 g fat. I add it to home-rendered lard and tallow and I add it to all of the liquid oils I use. So far so good.

 

[Louise Taylor]

You are right. I should have checked that. The supplier recommends 0.02 to 0.05% so I have overdone it.

I will have to see what happens with this one over time. Hopefully it will not be too yellow tomorrow :

Thanks for your help.

 

[AliOop]

What I can say is I've been using ROE for, oh, about 5 years now at a dosage of 0.5 g ROE per 1000 g fat. I add it to home-rendered lard and tallow and I add it to all of the liquid oils I use. So far so good.

@DeeAnna i never thought of adding ROE to my home-rendered lard and tallow, so thanks for mentioning that!

Does using the ROE change how you store the rendered fats, i.e., refrigerated v room temp? Although I’ve heard that well-rendered lard can be stored at room temp, I’m not confident that my rendering is clean enough, so I prefer to refrigerate.

ETA: do you have a favorite supplier for ROE, and does this product go by any proprietary names? I’m happy to research a bit but want to use the correct search terms. Thanks!

 

[DeeAnna]

I think (didn't look to be sure) I'm currently using ROE from Lotioncrafter, but I've also bought it from Majestic Mountain Sage and other reputable suppliers. I don't think there is any single company that is the go-to source. You can read more about ROE and its various names in my Soapy Stuff article on ROE. Soapy Stuff: Soapy Stuff

I prefer to refrigerate home rendered lard and tallow if I have room, because I'm not 100% confident of my rendering skills either. I don't render often enough to figure out the best method.

 

[AliOop]

@DeeAnna thank you, that article and the additional info you shared are very helpful!