Will this soap be too soft?

[Natchanon]

Hi, I have a couple of questions.

1. So, I ordered some soap bars from a soap maker, and the soap turned out to be drying and I itched all over my torso after using it. Is it because the their recipe is too cleansing? Pretty sure 25 is too high. The SF is rice bran.
I have to wash my body really well to avoid the itch. I'm starting a soap for men business so I don't want that inconvenience and irritation for my customers.

2. I'm tweaking the recipe to reduce cleansing to 15. Now I'm worried it will be to soft and disintegrate if left in the moist environment of a bathroom. Will these hardness and iodine values be enough to make an averagely hard bars. I could kick the hardness up to 40 and cleansing to 16, though I don't think 1 point matters much.

 

[DeeAnna]

Mushy soap happens when any soap sits in a puddle of water between uses. Soap must be allowed to drain and dry as much as possible. In a humid climate, this is especially important.

I believe you are thinking a physically hard bar will be a long-lasting bar. Hardness is only part of the story. Ice is hard but melts fast. Rock is hard and doesn't melt. Which lasts longer?

Your soap should be sufficiently hard like ice or rock, that is true. But it also should be less water soluble -- like rock.

The "longevity" number is a measure of insolubility. Most people who want a longer lasting bar try to get this number at least 30 if not higher. Soapcalc does not calculate this number (some calcs don't), but you can calculate it yourself -- add the stearic acid and the palmitic acid percentages. For your recipe, the longevity number is 17 + 7 = 24.

Your second recipe is using "water as % of oils" as the way to calculate the water content. Start using lye concentration (or water:lye ratio) to get better consistency and control as you design recipes. Most people do well with a lye concentration of about 33%. You can tweak this up (less water in the recipe) or down (more water) as you learn what works best for you.

Your itchy skin could come from the large amount of coconut oil in the first recipe. It could also come from the soap having excess lye remaining in the bar. It's hard to know which one was the problem.

In the first case, reducing the "cleansing" fats (coconut, palm kernel, babassu, etc.) is the solution, as you are doing.

In the second case, the solution is always calculating the recipe to ensure it is safe (as you are doing), weighing the fats and NaOH accurately, and allowing the soap to cure long enough.

If you are making soap with a cold process method, adding the superfat at trace is not useful. The lye is still very active at that point and will react with your "superfat fat" as well as the other fats. So there is no benefit to this -- just add all the fats in the beginning.

If you are using a hot process method, adding the superfat later is theoretically a reasonable thing to do, but there's a practical problem -- the most common reason why soap is lye heavy is the soap maker forgets to add a fat. This is very likely when the soap maker tries to add fat after the soap is cooked.

 

[TheGecko]

Hi, I have a couple of questions.

1. So, I ordered some soap bars from a soap maker, and the soap turned out to be drying and I itched all over my torso after using it. Is it because the their recipe is too cleansing? Pretty sure 25 is too high. The SF is rice bran.
I have to wash my body really well to avoid the itch. I'm starting a soap for men business so I don't want that inconvenience and irritation for my customers.

2. I'm tweaking the recipe to reduce cleansing to 15. Now I'm worried it will be to soft and disintegrate if left in the moist environment of a bathroom. Will these hardness and iodine values be enough to make an averagely hard bars. I could kick the hardness up to 40 and cleansing to 16, though I don't think 1 point matters much.

A 5% SuperFat for 37% Coconut Oil is too low. The "itch" you are experiencing is because all the natural oils have been stripped from your skin. Since men tend to tolerate high amounts of CO as compared to women, I would try a batch where I dropped the CO to 30%, increase the Olive Olive Oil. I'd also decrease the Castor Oil, but that is just me.

As for making the soap last longer...the Grand Canyon in the United States is a good example of what water will do to rock...over time. Regardless of how 'hard' your soap is, if it sits in a puddle of water all the time it's going to absorb that water and become soft. Just the simple act of putting your soap on a rack and letting it dry between uses will increase the longevity of your soap. My BIL showers every day with my soap and a bar lasts him just over a month.

 

[Zing]

Your tweaked recipe is very close to my basic recipe. I love castor oil but use it at 4-6% -- high amounts can cause softness. I can tolerate a lot of coconut oil -- but that 37% is too much even for me! I use between 20-29% -- most members here use far less.
I have several soap saving pads in my house, and have also given them to people who get a lot of my soap. I too once thought longevity and hardness were synonymous but learned the difference from smarter people here.
Have fun tweaking and keep us posted.

 

[Natchanon]

Mushy soap happens when any soap sits in a puddle of water between uses. Soap must be allowed to drain and dry as much as possible. In a humid climate, this is especially important.

I believe you are thinking a physically hard bar will be a long-lasting bar. Hardness is only part of the story. Ice is hard but melts fast. Rock is hard and doesn't melt. Which lasts longer?

Your soap should be sufficiently hard like ice or rock, that is true. But it also should be less water soluble -- like rock.

The "longevity" number is a measure of insolubility. Most people who want a longer lasting bar try to get this number at least 30 if not higher. Soapcalc does not calculate this number (some calcs don't), but you can calculate it yourself -- add the stearic acid and the palmitic acid percentages. For your recipe, the longevity number is 17 + 7 = 24.

Your second recipe is using "water as % of oils" as the way to calculate the water content. Start using lye concentration (or water:lye ratio) to get better consistency and control as you design recipes. Most people do well with a lye concentration of about 33%. You can tweak this up (less water in the recipe) or down (more water) as you learn what works best for you.

Your itchy skin could come from the large amount of coconut oil in the first recipe. It could also come from the soap having excess lye remaining in the bar. It's hard to know which one was the problem.

In the first case, reducing the "cleansing" fats (coconut, palm kernel, babassu, etc.) is the solution, as you are doing.

In the second case, the solution is always calculating the recipe to ensure it is safe (as you are doing), weighing the fats and NaOH accurately, and allowing the soap to cure long enough.

If you are making soap with a cold process method, adding the superfat at trace is not useful. The lye is still very active at that point and will react with your "superfat fat" as well as the other fats. So there is no benefit to this -- just add all the fats in the beginning.

If you are using a hot process method, adding the superfat later is theoretically a reasonable thing to do, but there's a practical problem -- the most common reason why soap is lye heavy is the soap maker forgets to add a fat. This is very likely when the soap maker tries to add fat after the soap is cooked.

Thank you, DeeAnna. I gave the soap maker some specifications like "moisturizing and not too harsh". I thought she knew what she was doing. I ordered the soap around mid Feb. It arrived mid March, then I waited until yesterday to try it, so pretty sure it's not lyre. They were rock solid when they arrived, so I'm sure they had had enough time to cure.

 

[Zany_in_CO]

I'm starting a soap for men business

Instead of trying to design a soap when you know little about soapmaking, I'd suggest you do a Tried & True recipe like

Basic Trinity of Oils starter formula

I don't think you will be disappointed. It's good for all skin types. Allow a full 4-6 weeks cure.

 

[Natchanon]

Instead of trying to design a soap when you know little about soapmaking, I'd suggest you do a Tried & True recipe like

Basic Trinity of Oils starter formula

I don't think you will be disappointed. It's good for all skin types. Allow a full 4-6 weeks cure.

That's great. I've been looking for these. Thanks!

 

[DeeAnna]

I don't think you should rule out excess lye without a definite test to confirm. If the soap is made with enough excess lye, it will remain permanently lye heavy.