Calculating SF with Goat Milk

[ronrho56]

I have been making a goat milk soap, but am not clear on how to calculate the SF when using the milk? How do you take into account the fat content when using goat milk?

My basic recipe:
40 % Lard (409 grams)
40% Olive oil (409 grams)
15 % coconut oil (154 grams)
5 % castor (52 grams)
Using goat milk powder to equal 100 % of the liquid
NaOH 143 grams
Liquid 290 grams
SF at 5%

A I have not been able to wrap my head around how to calculate the SF. Any help would be appreciated.

 

[Dorymae]

Some lye calculators list milk fat if you wish to include it when figuring SF. If you are not picky with superfat, and your batch is 3 lbs - 5lbs( soap not oil) you can figure it will raise your superfat a few percent and not worry about it.

 

[ronrho56]

Thank you so much Dorymae for your quick response. One thing that I am unsure of though, is when using the milk in the calculators, do you then include the milk as one of your fats, or is calculated as the liquid?
Hope this makes sense.

 

[KristaY]

I just did this same thing last week, lol. I was using coconut milk and wanted to calculate the fat so I would know just where I was. Here's the link to my thread:

http://www.soapmakingforum.com/showthread.php?t=51437

This should help. Basically you'll need the nutrition info on the packaging to do the math. If you want an extra check on your calculations, post your fat grams per measurement listed on the product and how much you plan to use, and we can definitely double check it. Good luck!

 

[seven]

how much gm powder in grams are you using? look at the container for the fat content, then you'll be able to figure out how much milk fat is there in the formulation.

 

[ronrho56]

Seven, my total liquid was approx 10.3 oz (290 grams), and so I used approx 1 and 1/2 servings of goat milk powder per the directions on the can. The amount of fat in one serving is 7 grams, so approximately 10.5 grams of fat from the goat milk was added to the soap batter that was already at a 5 % superfat.
I just can't wrap my head around how to figure out the total superfat of the soap; is it even worth worrying about?

 

[Dorymae]

Thank you so much Dorymae for your quick response. One thing that I am unsure of though, is when using the milk in the calculators, do you then include the milk as one of your fats, or is calculated as the liquid?
Hope this makes sense.

Milk is a liquid, even if you are using powder you need to reconstitute it, whether it be in you lye liquid or it being in the soap batter it will reconstitute. Therefore you would use the reconstituted amount (liquid) for the milk fat amount. It should tell you on the package how much liquid will reconstitute one cup. You need to adjust from there.

 

[ronrho56]

Thank you so much KristaY; I will definitely look at your thread.
And thanks again Dorymae for the reply! The milk is consider as part of the liquid; I guess what I meant is. do you go ahead and add the milk fat as part of the fats in the recipe, therefore using less of the other fats? It is so confusing to me!

 

[KristaY]

Seven, my total liquid was approx 10.3 oz (290 grams), and so I used approx 1 and 1/2 servings of goat milk powder per the directions on the can. The amount of fat in one serving is 7 grams, so approximately 10.5 grams of fat from the goat milk was added to the soap batter that was already at a 5 % superfat.
I just can't wrap my head around how to figure out the total superfat of the soap; is it even worth worrying about?

If you're using soap calc you can put the 10.5 gm in "milk fat, any bovine". This will re-calculate the lye needed. You can then decide if you want to increase the lye to keep your SF at 5% or you can leave it the same. I played around with soap calc to figure out how much the SF was increased and it came out to an additional 5% with the added 47 gms coconut milk fat.

 

[Dorymae]

Thank you so much KristaY; I will definitely look at your thread.
And thanks again Dorymae for the reply! The milk is consider as part of the liquid; I guess what I meant is. do you go ahead and add the milk fat as part of the fats in the recipe, therefore using less of the other fats? It is so confusing to me!

When you add milk fat, it will add to the fats in your recipe. When using a soap calculator the program will take that into account and adjust your lye amount automatically according to the SF amount you have chosen. You can keep your oils the same, the program will adjust the amount of lye you add.

 

[ronrho56]

Thank you everyone; I will have to play with soapcalc when I have a few, and try what you have suggested.

 

[reinbeau]

I just figure it adds 2-3% to my SF. I SF at 6, so the GMOH I make ends up at about 8 or 9%, which is just fine with me.

 

[xraygrl]

Like Reinbeau I don't ever figure the fat in the milk into the lye calculations. It just gives me a little bit higher SF and I am just fine with that. :grin: