How to make soap out of old and possibly rancid lard and cooking oils (need advice)

[kenny203]

I have some expired oils which have been subjected to a wide range of temperature fluctuation for the last 6 years. I don't know if the oils are rancid or not as they've never been opened, but I'm assuming that they probably HAVE gone rancid by now and would like to know how to make soap out of these oils.

About myself:

I have experience as a cold process soapmaker and need some advice on how to make soap out of rancid oils.

Thank you.

 

[Yooper]

Well, it would make it the exact same way as with good oils. The thing is the soap would go rancid or be rancid and get stinky so you really don’t want to even try. If you’re desperate, and you have the light to waste, go ahead and try it, but ensure if it doesn’t smell bad when it’s first made and doesn’t have dreaded orange spots on it to use it up quick. rancid is rancid and unfortunately, you can’t erase rancid.

 

[kenny203]

Well, it would make it the exact same way as with good oils. The thing is the soap would go rancid or be rancid and get stinky so you really don’t want to even try. If you’re desperate, and you have the light to waste, go ahead and try it, but ensure if it doesn’t smell bad when it’s first made and doesn’t have dreaded orange spots on it to use it up quick. rancid is rancid and unfortunately, you can’t erase rancid.

I've heard that it's actually quite possible to make a soap out of rancid oil using the hot process method with zero percent superfat. Is that just an urban legend ?

 

[Yooper]

Well, sure it’s possible and it’s also possible to do it cold process. The outcome is not going to be very good at at least not for very long. That’s all. If it’s for personal use and you’re going to do laundry or dishes or basic handwashing it’s probably fine if the soap does not smell too bad.