What stage in cold process do you add it ?According to Kevin Dunn, proteins do not break down completely to amino acids when mixed with NaOH. Some less drastic changes do occur since we know silk fiber eventually dissolves in lye solution. Ditto for the proteins in dairy. The bottom line is that proteins seem to mostly survive the soap making process with some minor changes.
The benefits of adding proteins for the soap itself? The usual thought about silk protein is that it may increase the bubbliness of the lather. Some claim it also gives the lather a silky feel. Blind testing with goat milk soap has had variable results. Some testers see no difference between goat milk soap and the same soap made without milk. When testers do claim a difference, that could be due as much from the added sugars and/or fat from the milk, since milk is more than just protein. IMO, the use of protein in soap only makes a small difference in the skin feel and lather.
The benefits of adding proteins for the skin? If collagen actually helps the skin, which is something I'm not qualified to answer, it's better used in a leave-on product, not in a wash-off product like soap. I know hydrolyzed proteins are used in conditioners, however, so ...
Try it and have fun. Nothing horrible will happen ... but I think it's fair to say there won't be any amazing benefits either.
What stage in cold process do you add it ?
Sounds good . Thank youNot sure - never done this and don't know anyone else who has used collagen. If it is in solid form, it will need to be rehydrated in water first. Adding stuff at trace isn't all that useful, so my guess is either use the rehydrated collagen to make the lye solution or mix it into the fats before adding the lye solution.
However you do it, be sure to include the water used with the collagen as part of the total water requirement.
Be careful resurrecting threads that are 6 years old. The Efficacious Gentleman and I happen to be around yet, but all the others are inactive. You're more likely to get more useful responses if you start a new thread to ask your question and include a link to the old thread to give people a point of reference.