Hello, soapers, I'm new. I bought some duck lard but it has salt and mysterious 'spices' in it. Is it ok to use like that. Does it change the saponification value? What does salt do in the soap? Thanks for the feedback!
Not knowing what the spices are, I don't want to guess about whether they could affect the soap.
You could clean the duck fat like the way one would clean bacon grease, which usually has lots of seasonings in it. I have even cleaned chicken grease (schmaltz) and used it in soap. The only things I couldn't get out of it were turmeric and paprika that I had used to season the skin, and which colored the fat even after washing. Since both of those are used as colorants in soap, I didn't worry about it. However, I didn't find that schmaltz made good soap when used over ~10%. If duck fat is similar, you may want to keep the percentage low.
Thanks for your replies! I'm quite new at soapmaking but I've made a couple batches and I like using animal products and I also like experimenting myself but it sounds like it's pretty unanimous that it's not the best fat to use. Concerning the German cuisine, I've never really tried. Do you eat those while playing with Teetotums? Sounds like a medieval party. :O