Here are the amounts of everything i use. I'm not sure if the % is based off the total weight of the ingredients or the total weight of the oils. I'm still trying to figure a lot of this out.
Shea Butter-10oz
Coconut oil-10oz
Glycerin-4oz
Jojoba oil-4oz
Castor oil-2oz
Distilled water-13oz
Sodium hydroxide-3oz
Potassium hydroxide-1oz
As I've said, this recipe produces a great shave that I really like, but I'd like the lather to last a little longer on my skin. Is there anything I should add, or reduce, to get that outcome?
Welcome to the forum!
So you want your lather to last a while longer and not evaporate. Actually the lather doesn't evaporate, it collapses. No structure to support all the tiny bubbles of lather foam.
Let's dissect this somewhat...
1. For a good shave soap you want the fatty acids percentages to be at LEAST 50% Stearic Acid as displayed on the calculator. That is using a combination of fats such as stearic acid, tallow, cocoa butter, etc.. Your recipe as listed shows a 17% percent stearic acid percentage of all oils.
2. Way too much shea butter. It's a great oil but cut it back to about no more than 10% of the oil weight in total.
3. Too much glycerin. Should be added post-cook too. Use no more than 10% of total oils weight, which in your case is 2.6 oz. not 4 oz. Too much glycerin in a soap will reduce it's lathering ability.
4. I don't know what your superfat percentage is, but for good shave soap it should be in the 7-8% range.
5. Basically shave soap is a type of "cream soap". I would recommend a minimum of 60% potassium hydroxide. KOH makes it easier to quickly create lots of thick creamy lather.
6. Basically you've made a type of bar soap here, not a shave soap. ALL SHAVE SOAP will have some measure of stearic acid in the formula. Check out all the popular ones being sold online such as CELLA, RAZOROCK, TAYLOR OF OLD BOND STREET, etc. Stearic acid is usually the first or second ingredient listed. It is what really gives the shave soap dense, creamy body. Also the majority of classic men's soaps use tallow. It really improves the shave experience considerably.
Now there are some, shall we say, "unscrupulous" vendors that take melt & pour soap bases and scent them up and re-label as "shave soap" M&P uses a lot of glycerin in it, it has to in order to be melt & pour. But it's lather sustaining ability is nil. Use no more than 10% of glycerin to oil weight and add it in the post-cook stage.
7. Cut back on the coconut oil too, around 8-9% of total oils used is a good percentage.
8. Your water to lye concentration is around 23% which is good.
Remember that you are making a shave soap, not a cleansing bar of soap. Totally different soap profile compared to regular bar soap.
Use the Soapmaker Friend Calculator to compare on the bar charts how the various oils used affect the end product's properties.
I noticed all of your amounts are basically rounded off amounts to the nearest ounce. Do you have a decent scale that is capable of measuring in grams? Even better if measuring to the 1/10th of a gram.
I don't where those lye amounts came from but they're quite inaccurate when it comes to making a quality shave soap. The calculator shows the the KOH should be 1.34 oz. and the NaOH should be 2.58 oz. However, again I highly recommend you use a minimum of 60% KOH and 40% NaOH. My own formulas I use an 80/20 ratio of KOH to NaOH.
Try using sorbitol to enhance the lathering ability of the soap. Around 3% of oil weight for sorbitol is a good start. It is a naturally occurring sugar alcohol found in many fruits and vegetables. Add it in with the the lye water at the start.
Here is my recommendation for a good start at shave soap:
50% Stearic Acid
20% Beef Tallow
7% Shea Butter
7% Cocoa Butter
8% Coconut Oil
8% Castor Oil
65/35 KOH to NaOH ratio
I hope these suggestions help you. Please take them in the spirit given. Carrie Siebert's book have been my guide through my shave soap formulation process. I don't make hard puck soaps, instead I make a cream shave soap similar to CELLA or RAZOROCK.
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