Difference between using Sodium Lactate and Table Salt in CP Soap for hardening

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cosmicomic

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Hello!!

I wanted to understand the difference between using Sodium Lactate and Table Salt (used as a hardener) when it comes to hardening soap.
I've been using 1 tspn per KG of oils in my recipes (Which are roughly 48% unsaturated fats and 52% saturated fats) and i do find that my loaves are easier to unmould. But I recently learnt that this doesn't necessarily lead to a harder and longer lasting bar of soap, it only makes it easier to unmould. While on the other hand, sodium lactate not only helps unmould but also leads to a harder, longer-lasting bar. Is this true?

Do both ingredients do exactly the same thing or is there a difference in the final product (if both have the exact same recipe)
 

lsg

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Sodium lactate also helps lather. IMO, salt can decrease lather. If you are looking for harder bars, then you might check out threads on this forum concerning the use of soy wax.
 
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I don’t find that either salt or SL make my bars harder in the long term, just faster unmolding. Vinegar as a partial or full water replacer does harden them and help with unmolding, but probably not overly noticeable in the end product, either (although I like the lather feel with vinegar).

Look for fats, oils, and butters that increase hardness.
 

DeeAnna

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I question whether any of these salts -- sodium lactate, table salt, vinegar (which turns into a salt when it reacts with lye), etc. -- do much if anything to increase the longevity of the soap.
 

TheGecko

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Do both ingredients do exactly the same thing or is there a difference in the final product (if both have the exact same recipe)
They aren't exactly the same. As noted by @lsg, table salt can reduce foam (lather), while sodium lactate can improve it. Table salt, which is primarily Sodium Chloride can be used as a preservative...when used on meats like beef, pork and fish, it dries it out. Sodium lactate is the sodium salt of lactic acid and lactic acid occurs naturally in the skin and is a humectant.

I use SL at 1 tea PPO for the purpose of making my soap easier to unmold earlier than later which means I can turn my molds around faster as opposed to having to purchase more molds. If my molds have more intricate designs, I will increase the rate to 1 1/2 to 2 tea PPO depending on weather and give them an extra day. I haven't noticed that SL produces a harder bar overall as opposed to not using SL and then waiting two or three days to unmold and/or cut.

On the other hand, using table salt doesn't seem to produce an overall physically harder bar of soap and in a shorter amount of time. But it should be noted that just because the bar is physically harder doesn't not mean that it will last longer. How long the bar will last is dependent on the water solubility of your oils/butters. The more water soluble, the faster it will get used up.
 

cosmicomic

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Thank you @
They aren't exactly the same. As noted by @lsg, table salt can reduce foam (lather), while sodium lactate can improve it. Table salt, which is primarily Sodium Chloride can be used as a preservative...when used on meats like beef, pork and fish, it dries it out. Sodium lactate is the sodium salt of lactic acid and lactic acid occurs naturally in the skin and is a humectant.

I use SL at 1 tea PPO for the purpose of making my soap easier to unmold earlier than later which means I can turn my molds around faster as opposed to having to purchase more molds. If my molds have more intricate designs, I will increase the rate to 1 1/2 to 2 tea PPO depending on weather and give them an extra day. I haven't noticed that SL produces a harder bar overall as opposed to not using SL and then waiting two or three days to unmold and/or cut.

On the other hand, using table salt doesn't seem to produce an overall physically harder bar of soap and in a shorter amount of time. But it should be noted that just because the bar is physically harder doesn't not mean that it will last longer. How long the bar will last is dependent on the water solubility of your oils/butters. The more water soluble, the faster it will get used up.
Thank you so much for the extremely insightful answer. that does make sense. I didnt realise that a harder bar doesn't mean a longer-lasting bar. that's a big learning for me from this. Thank you!
 

cosmicomic

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Sodium lactate also helps lather. IMO, salt can decrease lather. If you are looking for harder bars, then you might check out threads on this forum concerning the use of soy wax.
Thanks @lsg I'll have a look at using soy wax!
 

cosmicomic

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I don’t find that either salt or SL make my bars harder in the long term, just faster unmolding. Vinegar as a partial or full water replacer does harden them and help with unmolding, but probably not overly noticeable in the end product, either (although I like the lather feel with vinegar).

Look for fats, oils, and butters that increase hardness.
Thank you! Ive found the same with Salt. I did find a slight improvement in being able to unmould the soaps as compared to when i made the recipes earlier, but it is a marginal difference.

I didn't know vinegar could help harden as well! I made a bunch of Kombucha soaps, not the same as Vinegar i know but they did give a lovely lather as well.
 

earlene

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Thank you! Ive found the same with Salt. I did find a slight improvement in being able to unmould the soaps as compared to when i made the recipes earlier, but it is a marginal difference.

I didn't know vinegar could help harden as well! I made a bunch of Kombucha soaps, not the same as Vinegar i know but they did give a lovely lather as well.
A few years ago I made Kombucha soap for my SIL who makes her own Kombucha tea, because I figured she'd like the novelty. I learned that there are others who also like Kombucha soap. Yes, it's the sugar content that contributes to the bubbles and lather. It also really caused my lye solution to heat up so fast, it was my first and only 'boil-over' lye solution experience.

It's been quite awhile since I've made any kombucha tea soap though. I think I may still have one bar left, so perhaps I'll make some more soon.
 

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