Using Vinegar to harden Goat Milk Soaps

[Keaaukb]

I’ve read through many of the threads here relating to using vinegar as a hardener, I have found the calculations for water-based recipes. I’m wondering about how to adapt this for milk-based.

I currently use 100% frozen goat milk to combine w sodium hydroxide. I can’t imagine that the milk would want to combine with the vinegar in the same way water does. I’m going to play with it a bit, but thought maybe someone could save me some time.

I do mostly HP, am wondering if some variation of adding at cook (as I currently do w sodium lactate) would work.

It’s a challenge getting sodium lactate here, and I’d love another option.

 

[cmzaha]

Your best way with gm is to use a 50/50 meaning using 50% of your liquid as gm and 50% of your liquid as vinegar. Multiply the amount of vinegar by 0.0357 for your extra lye. You can dissolve your lye in the vinegar or half the lye in your gm and half in the vinegar to be sure all your lye dissolves. This is the method I would use if using gm. Personally, I used powdered gm and just mixed it in my warm oils because I always soaped with vinegar. Hopefully, this makes sense.

 

[Keaaukb]

Many thanks! This is exactly what I needed

 

[cmzaha]

 

[Nona'sFarm]

So know this is a little off subject - when you make ricotta cheese, you add an acid to milk and the milk curdles. Why don't you end up with cheesy soap when you combine milk, vinegar, lye and oils? This curious mind wants to know.
Though anyone can answer me here, I am going to call on @ResolvableOwl to help with this mystery that science can probably explain.

 

[ResolvableOwl]

when you make ricotta cheese, you add an acid to milk and the milk curdles. Why don't you end up with cheesy soap when you combine milk, vinegar, lye and oils? This curious mind wants to know.

You're effectively not adding vinegar (free acetic acid), but sodium acetate! With so much lye, any vinegar will be neutralised and just has no chance to pull the milk into acidic pH regions.

Milk (casein protein) curdles in the acidic (when it goes sour, by itself or with added vinegar/lemon juice/yoghurt).
Even if you add the vinegar first, the milk will flocculate – but once you add lye, the caustic alkali will reverse this, and etches away all this grainy protein jelly.

That's how drain cleaner works, and also why you can salvage seized cheese sauce with baking soda. You can tell just how rude the soapmaking lye is to proteins by the slight ammonia smell of the batter – free ammonia is not normally a constituent of food, but the lye is so strong that it literally rips apart protein molecules, liberating their amine moieties as ammonia gas.

 

[Nona'sFarm]

@ResolvableOwl , thanks. So fascinating!

 

[meena.shah]

Hi I haven’t heard of vinegar in soaps can you please tell me if we make what percentage of lye to add.

 

[AliOop]

Per Carolyn's post #2 above: Multiply the amount of vinegar by 0.0357 for your extra lye.

You can also read more about it here on DeeAnna's website: Acetic acid (Vinegar) | Soapy Stuff

 

[Trinbago27]

This is super interesting! Can citric acid still be used with the vinegar?

 

[AliOop]

This is super interesting! Can citric acid still be used with the vinegar?

You can get some not great results when combining the two. The soap can be a bit rubbery, or have crystals. I switched to sodium citrate instead of citric acid and haven't had issues since.

 

[Trinbago27]

Super intriguing… will try with an 8oz batch

 

[Trinbago27]

Btw, what is the advantage, if any, yo using vinegar vs salt?

 

[AliOop]

Salt inhibits lather, and vinegar does not. I also feel like the lather from vinegar has a certain feel to it that I like, but that I can't quite put into words.

 

[Trinbago27]

Got it!

Thanks

 

[Kari Howie]

Salt inhibits lather, and vinegar does not. I also feel like the lather from vinegar has a certain feel to it that I like, but that I can't quite put into words.

Ali, do you use Na Lactate if you’re using vinegar?

 

[AliOop]

Ali, do you use Na Lactate if you’re using vinegar?

I don't tend to use sodium lactate at all, unless I'm using more water than my typical 40% lye concentration, and want the soap to firm up faster.

Since I started MB'ing my lye solution, I've also stopped using vinegar as often, for a fairly silly reason. In SoapmakingFriend, the lye adjustment for vinegar doesn't work correctly if you also select the MB lye option. Yes, I could do the extra math calculation separately, but I tend to make mistakes whenever I do things like that. So, I just quit using vinegar unless I happen to be working with a fresh lye solution, and not master-batched.