Iodized salt in salt bar

[Ely]

Hi everyone
I have a question about salt bar.

Why should I use non Iodized salt for making salt bar? Most people here mentioned that and I don’t understand the reason behind that?
I checked the ingredients list on table salt and it has sodium chloride, potassium iodide, potassium Iodate.
There is no iodine molecules in salt to react with double bonds in fatty acids in soap.
Would you please someone explain the reason for not using Iodized salt?

Thanks in advance

 

[earlene]

I use whatever salt is available in the store when I add salt to my soap. Sometimes it is iodized and sometimes not. Not every store carries both. For the most part though, I try to buy non-iodized salt for adding to soap.

However, to answer your question as to why not use iodized salt. I suspect the reasoning is the combination of these two things:

From SoapCalc:

Iodine - As a general rule, the lower the number, the harder the bar and the less the conditioning qualities and vice versa. A recipe with iodine values higher than 70 will tend to produce a somewhat soft bar of soap. Definition: number of grams of iodine that will react with the double bonds in 100 grams of fats or oils.


From the Mayo Clinic:
Iodized salt in the U.S. contains 45 micrograms of iodine per gram of salt.

 

[Ely]

I use whatever salt is available in the store when I add salt to my soap. Sometimes it is iodized and sometimes not. Not every store carries both. For the most part though, I try to buy non-iodized salt for adding to soap.

However, to answer your question as to why not use iodized salt. I suspect the reasoning is the combination of these two things:

From SoapCalc:

Iodine - As a general rule, the lower the number, the harder the bar and the less the conditioning qualities and vice versa. A recipe with iodine values higher than 70 will tend to produce a somewhat soft bar of soap. Definition: number of grams of iodine that will react with the double bonds in 100 grams of fats or oils.


From the Mayo Clinic:
Iodized salt in the U.S. contains 45 micrograms of iodine per gram of salt.

Thanks a lot earlene for your reply. Did you face any problem when you use Iodized salt in large quantity for salt bar?

 

[cmzaha]

I have used Iodized salt in salt bars at 100% with no problems.

 

[Alfa_Lazcares]

I also use only iodize salt cause thats the only kind i can get, no problems. I use it at 50%.

 

[earlene]

Thanks a lot earlene for your reply. Did you face any problem when you use Iodized salt in large quantity for salt bar?

No apparent problems.

 

[KiwiMoose]

I use whatever salt is available in the store when I add salt to my soap. Sometimes it is iodized and sometimes not. Not every store carries both. For the most part though, I try to buy non-iodized salt for adding to soap.

However, to answer your question as to why not use iodized salt. I suspect the reasoning is the combination of these two things:

From SoapCalc:

Iodine - As a general rule, the lower the number, the harder the bar and the less the conditioning qualities and vice versa. A recipe with iodine values higher than 70 will tend to produce a somewhat soft bar of soap. Definition: number of grams of iodine that will react with the double bonds in 100 grams of fats or oils.


From the Mayo Clinic:
Iodized salt in the U.S. contains 45 micrograms of iodine per gram of salt.

Gosh - thanks for that Earlene. I did read up on Iodine and INS values way back when I started but it totally went over my head. Looking back in my previous recipes i can see that I average iodine of around 52% which is in the healthy range. What can contribute to higher or lower iodine in a recipe? I notice that some of my salt recipes have lower iodine, but that is surely a coincidence as the salt is not included in the soap calc calculation, so it was not taken into consideration by the online calculator.

 

[Mobjack Bay]

So much to learn about making soap... I also wondered about the iodine value. I did find a bit about it here on SMF, but also did a little research of my own. The iodine value isn’t used to measure the amount of iodine in a soap. The value is derived from a medical/food science lab test that is used to measure the type of fatty acids in an oil. The test determines how much added iodine will bond with the oil. The amount of iodine that will bond to the oil increases as the fraction of unsaturated fatty acids increases.

Oils with high iodine values are more reactive, less stable, softer, and more susceptible to oxidation and rancidification.

http://www.northcountrymercantile.com/soapmakinglibrary/iodine-values-of-various-soap-making-oils/
https://www.britannica.com/science/iodine-value
https://www.soapmakingforum.com/threads/ins-iodine.48355/

The value doesn’t tell us anything about how adding iodized salt to a soap recipe might affect the qualities of the soap. For those insights we will need to rely on the experienced soapmakers like @earlene!

 

[Mobjack Bay]

p.s. for @Ely

When dissolved in water, both potassium iodide and potassium iodate will “disassociate” into potassium and iodide or iodate , which are chemical forms of iodine. The same thing happens with sodium chloride.