Theory on Skin-Type Impact on Shave Soap Selection

Oily skin here representing. I find your post to be spot on. However, I will add that the formulation of the soap, even if super fatted can make a difference. Some super fat soaps are terrible for me, while others are sublime.

It took me a while to understand this as I couldn't figure out why people said that MdC was drying. Our personal skin chemistries are probably the biggest component to the YMMV equation.

Oily skin here representing. I find your post to be spot on. However, I will had that the formulation of the soap, even if super fatted can make a difference. Some super fat soaps are terrible for me, while others are sublime.

It took me a while to understand this as I couldn't figure out why people said that MdC was drying. Our personal skin chemistries are probably the biggest component to the YMMV equation.

Very True!

I think we could probably throw the local climate into the mix as well. for example, here in Philly, there's a fair amount of humidity in the summer, while the winter tends to get pretty dry.

I can see the logic in this, although SharpSpine's comment on formulation is also very true. I have dry skin and I actually use a moisturizer as a preshave, so that essential oils don't get into my skin and cause irritation. That being said, there are still some soaps that usually have very good pre-shaves that are just average for me. One that comes to mind is Mystic Water shave soap-the majority of people get wonderful post-shave with this soap but it's just OK for me. Two soaps that give me very good post-shave are B&M and Mike's, with honourable mention to Stirling.

I have to say though, I've never had post-shave irritation or massive drying with Shaver Heaven soaps, which are vegan, so I'm not quite sure if this explanation holds for me. It could be that something in the Shaver Heaven formulation that works for my skin.

Well, vegan soaps can be super-fatted just like tallow soaps can, so both types can be formulated to be moisturizing. The soap with (easily) the best post-shave I've used is Pannacrema Nuàvia, which is entirely vegan. In fact, its excess lather can be applied after the shave like a balm, and works well. So it seems to me the distinction is more between super-fatted soaps versus not, as opposed to veggie versus tallow. Maybe it's just that we're more used to super-fatted tallow soaps (B&M, CRSW, presumably MWF with its lanolin), while some (most?) of the better-known veggies aren't (MdC, Catie's, Proraso), but yeah, either type can be made to be moisturizing.

All that said, I fully admit I could be missing a particular quality of saponified tallow as far as moisturizing the skin.

This is a good thread and I think you categorized the skin types accurately. I have sensitive skin that is fairly dry and thus I like soaps with good moisturizing qualities.

There has been some discussion and/or questions about soaps that are superfatted and I want to share some of my thoughts on it. You can't tell if a soap maker is superfatting their recipe by merely reading the ingredients. Lye discounting (superfatting) is using less lye than what is required to turn 100% of the oils to soap. This is called superfatting on a lye calculator typically, and all you do is select the percentage of superfat and it tells you how much lye to use. I make bath and facial soaps via cold process and have never attempted to make a batch without superfatting, see below for details but basically safety is one reason because I don't want to risk having a lye heavy soap and because I want my soaps to be more conditioning for the skin. In regard to this thread I wanted to point out that superfatting can be used for a recipe no matter how many oils are used, thus MdC and other vegan soaps can indeed have superfatting. A soap maker can choose to add the extra oils in the beginning with all of the oils or after trace, or for hot process after cooking for a while (from what I've read on HP, I use CP so no experience with HP). Saponification for cold process continues for 1 to 2 days after pouring the soap into the mold so it's debatable if adding the superfat oils after trace has much benefit over adding them in the beginning since all of the oils are still at risk of saponification. As for hot process I can't say but I would think there is more benefit to adding them later versus cold process since the cooking process speeds up saponification. Below is some good info on the subject that I got from SoapCalc.com in case anyone is interested.

6. What is superfat or discount?
If you use all the lye necessary to exactly saponify all of the fatty acids in the oils, the soap would have no excess lye or excess oil (next to impossible without a chemistry lab). It would have a zero discount and there would be no superfat. If you discounted the lye, let's say by 5%, 5% of the soap would contain oils that have not chemically reacted with the lye. i.e. all the lye was used up in reacting with 95% of the oils. The soap would have a 5% superfat. These unspecified oils are good for conditioning the skin. A soap with no discount or superfat will clean better. However, other than conditioning the skin, there are other important reasons to discount the lye (or superfat the soap). Please see the next question.

7. Why is a minimum 5% discount recommended?
The SAP values used to calculate the amount of lye - in this calculator and in others - is an average. If you purchase oils/fats that have been assayed by a chemical lab, you will know the exact SAP value of the oils/fats. (Your wallet or purse will be a little lighter too). If you weigh these oils and the lye on very precise laboratory scales, you can confidently make a true zero discount soap.

One of my references gives the SAP value for coconut oil as 250-264. That is the Potassium Hydroxide SAP value, chemical symbol KOH. The SAP for other oils is specified similarly as a range of values. Why? There are many variables that contribute to the chemical qualities of a carrier oil. Here are a few to give you the general idea:

Species of the botanical used to make the oil.
Geographical location of the source botanical. i.e. variable climate.
Varying types of processes used to create the oil.
Seasonal differences in when the botanical was harvested.
Maturity of the botanical when it was harvested.
The minimum 5% discount/superfat is recommended to allow for these variances so you do not end up with soap that contains unused lye.

Hobbyist: great info and thank you for posting that insight into soap making.
herbert7890: Thanks for your thoughts and insights regarding why some soaps are great for some of us but not for others.

I have been intrigued lately why some soaps work for my skin (combination with rosacea) and others that should work instead irritate my skin.  First I looked at the ingredients, but then I bought a couple of soaps that should have been perfect and instead I got irritation.  That led me in the direction that Herbert wrote up so nicely.  

Great thread and I will be following it as more folks weigh in with their knowledge and experience.

This is a good thread and I think you categorized the skin types accurately. I have sensitive skin that is fairly dry and thus I like soaps with good moisturizing qualities.

There has been some discussion and/or questions about soaps that are superfatted and I want to share some of my thoughts on it. You can't tell if a soap maker is superfatting their recipe by merely reading the ingredients. Lye discounting (superfatting) is using less lye than what is required to turn 100% of the oils to soap. This is called superfatting on a lye calculator typically, and all you do is select the percentage of superfat and it tells you how much lye to use. I make bath and facial soaps via cold process and have never attempted to make a batch without superfatting, see below for details but basically safety is one reason because I don't want to risk having a lye heavy soap and because I want my soaps to be more conditioning for the skin. In regard to this thread I wanted to point out that superfatting can be used for a recipe no matter how many oils are used, thus MdC and other vegan soaps can indeed have superfatting. A soap maker can choose to add the extra oils in the beginning with all of the oils or after trace, or for hot process after cooking for a while (from what I've read on HP, I use CP so no experience with HP). Saponification for cold process continues for 1 to 2 days after pouring the soap into the mold so it's debatable if adding the superfat oils after trace has much benefit over adding them in the beginning since all of the oils are still at risk of saponification. As for hot process I can't say but I would think there is more benefit to adding them later versus cold process since the cooking process speeds up saponification. Below is some good info on the subject that I got from SoapCalc.com in case anyone is interested.

6. What is superfat or discount?
If you use all the lye necessary to exactly saponify all of the fatty acids in the oils, the soap would have no excess lye or excess oil (next to impossible without a chemistry lab). It would have a zero discount and there would be no superfat. If you discounted the lye, let's say by 5%, 5% of the soap would contain oils that have not chemically reacted with the lye. i.e. all the lye was used up in reacting with 95% of the oils. The soap would have a 5% superfat. These unspecified oils are good for conditioning the skin. A soap with no discount or superfat will clean better. However, other than conditioning the skin, there are other important reasons to discount the lye (or superfat the soap). Please see the next question.

7. Why is a minimum 5% discount recommended?
The SAP values used to calculate the amount of lye - in this calculator and in others - is an average. If you purchase oils/fats that have been assayed by a chemical lab, you will know the exact SAP value of the oils/fats. (Your wallet or purse will be a little lighter too). If you weigh these oils and the lye on very precise laboratory scales, you can confidently make a true zero discount soap.

One of my references gives the SAP value for coconut oil as 250-264. That is the Potassium Hydroxide SAP value, chemical symbol KOH. The SAP for other oils is specified similarly as a range of values. Why? There are many variables that contribute to the chemical qualities of a carrier oil. Here are a few to give you the general idea:

Species of the botanical used to make the oil.
Geographical location of the source botanical. i.e. variable climate.
Varying types of processes used to create the oil.
Seasonal differences in when the botanical was harvested.
Maturity of the botanical when it was harvested.
The minimum 5% discount/superfat is recommended to allow for these variances so you do not end up with soap that contains unused lye.

Very Nice post!!! In my post I refer to "Fatted Soaps" to soaps that have additional moisturizers in them besides the mere ingredients that can make a simple soap. I dont really refeer to the technical definition of Super Fatting (as Im no soap maker). For example, in my definition used, MDC, LPL or Caties bubbles are not fatted soaps, since the only contain ingredients to make the soap (potassium hydroxide, coconul oil, stearic acid, etc). In the same manner, Soap Commander is considered a fatted vegan soap since in addition to the normal ingredients required to make up the soap, it also contains Shea Butter, which is a moisturizer).

Hobbyist: great info and thank you for posting that insight into soap making.
herbert7890: Thanks for your thoughts and insights regarding why some soaps are great for some of us but not for others.

I have been intrigued lately why some soaps work for my skin (combination with rosacea) and others that should work instead irritate my skin.  First I looked at the ingredients, but then I bought a couple of soaps that should have been perfect and instead I got irritation.  That led me in the direction that Herbert wrote up so nicely.  

Great thread and I will be following it as more folks weigh in with their knowledge and experience.

Glad it was of help to you!!!! Thanks!

herbert7890, great thread!
onethinline, I agree, a non-tallow can be every bit as conditioning as a tallow. Tallow seems useful/practical though, due to the combination of its different fatty acids.
Here is a link to a chart of various oils and their properties.