Questions about Liquid Soap

[rperr2011]

Hi all! Some questions about liquid soap. I'm coming from a cold process solid soap background.

1.) Previous threads on this forum suggest dual/hybrid lye does not really have an effect on the final thickness of liquid soap. However, in this YouTube video, the soapmaker uses dual/hybrid lye at NaOH/KOH ratio of 30/70 and has what I consider to be a good final consistency (honey-like). Do you think the consistency of her product is due to a) her formula b) the use of dual/hybrid lye c) the water dilution amount she uses or d) some combination of these?

Cold Process Liquid Soap YouTube Video


2.) What is the ideal lye concentration to use in liquid soap? I saw on this post (Please help me with cpls) that Water @ 2 X KOH (lye concentration 33%) is better for cold process liquid soap while Water @ 3 X KOH (25% lye concentration) is better for hot process liquid soap. I am interested in cold process liquid soap (no added heat during saponification). Does this mean a 33% lye concentration is better for my purposes?

Thanks again for your time.

 

[AliOop]

Hi and welcome! Here are my thoughts:

1. Dual lye: This can thicken your LS, but you are right, the final viscosity is a result of several factors, most importantly, your complete recipe (including dual lye, salt or no salt, etc.) and your dilution rate.

2. Lye concentration: just like CP bar soap, the "ideal" lye concentration depends on your goals. For instance, less water helps the batter trace faster, but more water means faster/easier paste dilution. I tend to use 3:1 for CPLS, in part because of 3 and 4, below.

3. Glycerin isn't required, but I use it for every batch. It helps the batter reach the paste stage more quickly.

4. I do subtract the glycerine from the total water amount. I actually dissolve my KOH 1:1 with water, because that requires no supplemental heat (like it would if you were dissolving the KOH straight into the glycerin). Then glycerin makes up all my remaining liquid. I stick-blend it right into my oils before pouring in the lye solution, but you could also add the glycerin to your dissolved KOH solution. Either way works.

 

[rperr2011]

Hi and welcome! Here are my thoughts:

1. Dual lye: This can thicken your LS, but you are right, the final viscosity is a result of several factors, most importantly, your complete recipe (including dual lye, salt or no salt, etc.) and your dilution rate.

2. Lye concentration: just like CP bar soap, the "ideal" lye concentration depends on your goals. For instance, less water helps the batter trace faster, but more water means faster/easier paste dilution. I tend to use 3:1 for CPLS, in part because of 3 and 4, below.

3. Glycerin isn't required, but I use it for every batch. It helps the batter reach the paste stage more quickly.

4. I do subtract the glycerine from the total water amount. I actually dissolve my KOH 1:1 with water, because that requires no supplemental heat (like it would if you were dissolving the KOH straight into the glycerin). Then glycerin makes up all my remaining liquid. I stick-blend it right into my oils before pouring in the lye solution, but you could also add the glycerin to your dissolved KOH solution. Either way works.

Thanks for the response. So, to clarify your point in #4, if you were using dual lye, and wanted a liquid:lye ratio of 3:1, and the recipe called for 98.15 g total of KOH and NaOH, you would combine 98.15 g KOH+NaOH with 98.15 g water (1:1). Then add 98.15 x 2 = 196.3 of glycerin to your oils for a final "liquid:lye" ratio of 3:1?

 

[AliOop]

Thanks for the response. So, to clarify your point in #4, if you were using dual lye, and wanted a liquid:lye ratio of 3:1, and the recipe called for 98.15 g total of KOH and NaOH, you would combine 98.15 g KOH+NaOH with 98.15 g water (1:1). Then add 98.15 x 2 = 196.3 of glycerin to your oils for a final "liquid:lye" ratio of 3:1?

Yes, exactly

 

[Zany_in_CO]

Do you think the consistency of her product is due to a) her formula b) the use of dual/hybrid lye c) the water dilution amount she uses or d) some combination of these?

70% Olive Oil
15% Hemp Seed Oil
10% Mango Butter
5% Castor Oil
Lye solution was a NAOH/KOH ratio of 30/70 with a
superfat of 2%

a) her formula - Yes -- 10% mango butter and 2% SF contribute to thicker soap
b) the use of dual/hybrid lye - Yes
c) the water dilution amount she uses - Yes
d) some combination of these - all of the above are known to contribute to the thickness of LS. BUT. They also contribute to the lack of clarity. (OCD about clarity here. LOL)

For crystal clear soap, you can use the same recipe at 0% SF; use only KOH; and determine the optimum dilution rate by the FAs used (2% butter is better) and when the (fully saponified) paste completely dissolves in hot water 'all of a sudden' when the paste reaches 159°F-160°. The right amount of water occurs if a skin forms on the surface. Add just enough more water so the skin no longer forms. You're there.

FOR COLD PROCESS LS: Bring the batch to hard trace and stop there. Cover for 1-2 weeks until it is fully saponified using the clarity test or phenolphthalein drops to be sure. NOTE: Not necessary with dual-lye LS. Also, preservative is not necessary for fully saponified soap paste any more than it is necessary for fully saponifed hard bars.

 

[Zany_in_CO]

Thank you for sharing that video. I found it to be VERY Interesting, but tedious. Had she pre-determined the correct amount of water needed to dilute the batch ahead of time, it should shorten the process considerably.

What is the ideal lye concentration to use in liquid soap?

There are about as many different ways to make LS as there are LSers! LOL
Seriously? It all depends on the method and It varies according to the oils/fats/butters used.

DILUTION RATES (FOR NON-DUAL LYE LS) (COLD PROCESS OR HOT PROCESS)

 

[rperr2011]

70% Olive Oil
15% Hemp Seed Oil
10% Mango Butter
5% Castor Oil
Lye solution was a NAOH/KOH ratio of 30/70 with a
superfat of 2%

a) her formula - Yes -- 10% mango butter and 2% SF contribute to thicker soap
b) the use of dual/hybrid lye - Yes
c) the water dilution amount she uses - Yes
d) some combination of these - all of the above are known to contribute to the thickness of LS. BUT. They also contribute to the lack of clarity. (OCD about clarity here. LOL)

For crystal clear soap, you can use the same recipe at 0% SF; use only KOH; and determine the optimum dilution rate by the FAs used (2% butter is better) and when the (fully saponified) paste completely dissolves in hot water 'all of a sudden' when the paste reaches 159°F-160°. The right amount of water occurs if a skin forms on the surface. Add just enough more water so the skin no longer forms. You're there.

FOR COLD PROCESS LS: Bring the batch to hard trace and stop there. Cover for 1-2 weeks until it is fully saponified using the clarity test or phenolphthalein drops to be sure. NOTE: Not necessary with dual-lye LS. Also, preservative is not necessary for fully saponified soap paste any more than it is necessary for fully saponifed hard bars.

Thank you for this very informative post.

Why do you say that clarity test or phenolphthalein drops are not necessary with dual lye LS?

Can you clarify what you mean by finding the optimum dilution rate by the FAs used? Do you mean estimate the final dilution rate by estimating using the rule in your post, copied below:

100% Olive oil LS requires 15-20% soap to 85-80% dilution water.
100% Coconut oil LS requires 40% soap to 60%% dilution water.
50/50 combo of the above requires 40% soap to 60%% dilution water.
All other combos fall somewhere in between.

Do these ratios for calculating dilution water vary if dual lye is used?

Do you perform the 159°F-160° test with a small sample of the fully saponified paste then scale the amount of water up once you know the correct water/paste ratio?

You mention 2% butter is better. Does this apply to all butters, like cocoa butter? I was thinking of adding a small amount of cocoa butter to my recipe.

Lastly, do you recommend against dual lye technique due to your preference for clear LS?

Thanks again.

 

[Zany_in_CO]

Do these ratios for calculating dilution water vary if dual lye is used?

Good question!
Those ratios work for KOH-only LS as far as I know. I have NO experience with dual lye LS but, to me, from what I've seen, that seems to bring the batch to trace quicker with no need to wait for full saponification before diluting. That's just my perspective of the process. That's why I believe dual lye LS may work better for Beginners. ?

Can you clarify what you mean by finding the optimum dilution rate by the FAs used?

Prepare a list of "test ratios" ahead of time and take good notes. Using the recommended dilution rates, you can determine the optimum rate with a little T & E... Divide the paste into 3 or more portions. Be sure to weigh the paste. Dilute each portion with different ratios of water to see what works best for you. Once done, you know how much dilution water will be required the next time you make it.

ETA: I throw the test batches together and use it!

For the recipe from the video, I would try 1:4 ratio (20% paste to 80% water ) -- just to get a feel for the lather it makes. It may be thin (watery) for your taste, but the lather will amaze you, as it did me the first time I tried it. Plus it rinses off quickly and cleanly so you don't waste LS going down the drain because it takes longer and more water to rinse it all off.

Note: The amount of Dilution water is truly a matter of preference. I would not care for the diluted LS in the video unless and until I added a bit more water. By the same token, you might like it just as is. There is no right or wrong way to dilute. Please yourself.

 

[Zany_in_CO]

Thank you for this very informative post.

My pleasure.

Do you perform the 159°F-160° test with a small sample of the fully saponified paste then scale the amount of water up once you know the correct water/paste ratio?

You mention 2% butter is better. Does this apply to all butters, like cocoa butter? I was thinking of adding a small amount of cocoa butter to my recipe.

Lastly, do you recommend against dual lye technique due to your preference for clear LS?

Time for breakfast. I'll reply to these questions later.... as time allows.

 

[Zany_in_CO]

Do you perform the 159°F-160° test with a small sample of the fully saponified paste then scale the amount of water up once you know the correct water/paste ratio?

No, that's not the point. One of the first times I made a batch, I took the temperature of the batch at each stage of the process and discovered it happened at trace and when the paste dissolved all at once during dilution (up to that point, the water was hot but the paste was not as hot and didn't fully dissolve until it reached that temp.) Just one of those things I decided to try.

You mention 2% butter is better. Does this apply to all butters, like cocoa butter? I was thinking of adding a small amount of cocoa butter to my recipe.

Please read:
https://www.soapmakingforum.com/threads/what-to-expect-from-various-oils-in-ls.62864/

Lastly, do you recommend against dual lye technique due to your preference for clear LS?

Not at all. There are so many different ways to make LS that I can't recommend one over the other. It's just a matter of finding the method that works for you.