Cold Process soap sweating

[Soma]

Hi all,
I already asked this question in a thread and then realized that it was two years old thread. So I am posting it here again.
I made a huge batch of CP soaps for a hamper order. They were curing nicely. Then came the rains. Humidity is 85-90% here. Suddenly all the soaps have started sweating profusely. I think it's the humidity, but not sure. I had added salt in the recipe for creating hard bars and early demolding because the client wanted the soaps earlier. I also put in orange and lemon essential oils. I am sharing my recipe . I would appreciate your advice.
Rice barn oil - 40%
Olive oil - 26.67%
Coconut oil - 20%
Safflower oil - 6.67%
Sweet almond oil - 3.33%
Castor oil - 3.33%
NAOH - 410.67g
Distilled water - 205.34g
Salt - 4.5 tsp
Sugar - 1.5 tsp
Orange and lemon Eo - 30g

I multiplied the above recipe X4. I covered them and let them go through gel phase for faster curing. This recipe gave me a lot of time to finish my swirls and design. I could unmold the loaves within 12 hours. They were nice and hard bars and curing nicely. But now......sigh....
Please help? Should I do rest of curing in an air conditioned room?

Hi again,
Just wanted to know if a dehumidifier will help in drying the cp soaps in humid climate.

 

[Babyshoes]

Hi again,
Just wanted to know if a dehumidifier will help in drying the cp soaps in humid climate.

It certainly won't hurt given your high humidity. See if you can get them to dry out a bit while you wait for more answers.

I'll let the more experienced soap makers chime in on the more technical side of your questions.

Bear in mind this is an international forum so you won't always get the replies you want the same day. I'm in the UK, and this thread was posted during the early hours of this morning my time.
It seems to me that it's usually busiest in here when the folks in America are getting home from work...

 

[ResolvableOwl]

because the client wanted the soaps earlier.

go through gel phase for faster curing

There is no shortcut to a proper curing. Gel phase (forced gel, CPOP, HP), salt (sodium chloride/lactate/acetate) help only to ease unmoulding, but can't speed up the internal solidification of the soap microstructure. Tell your customers the manufacturing date and that they should do themselves a favour to not use it at least until one month has passed. Particularly if early handover is logistically necessary. A bummer that sweating definitely does not help with that.

Your oil blend is okay, though it is high-oleic and rather low in “hard” fats/fatty acids. Thus it tends to take a bit longer until cured to agreeable performance.
For future recipes, a tick more “hard oils”, particularly stearic acid, helps the soaps to harden up quicker, and to last longer under “wet” conditions (bathroom, shower, but also humid weather in general) and to not become soft and mushy so quickly at wet places.

The recipe is a bit weird since oils are given in percentages, but other ingredients in absolute mass units, i. e. can't judge superfat, salt/sugar ppo rates etc. (I could guess you're referring to 3 kg oils @ 5% superfat, but I'd be happier with having this information from you). And how do you obtain 67% lye concentration?

For this batch, I guess a dehumidifier can in fact help you with “restarting” cure, i. e. getting water out more or less forcibly. Not sure about AC, depends on how strong it is to dehumidify the air. And I hope the drying sweat droplets don't ruin the surface of your bars!
But be aware that if it's humid at you, it'll probably be humid at your customer(s) too. Tight sealing with plastic wrap would be appropriate, but on the other hand, this would as well stop water evaporation, i. e. slow down curing again – you actually can't afford further curing delays, but you want to deliver the soaps. It's really a tricky situation.

 

[Soma]

Hi,
Thank you for the answers Babyshoes and Resolvable Owl.
I fed in the recipe in the lye calculator. I wanted a cleansing below 15. Some of my clients have given me a feedback of dryness when cleansing was over 15. That's why so many soft oils. Didn't want butters or other hard oils because had a lot of swirls that client wanted. Super fat was 5%. water lye ratio was 2:1. In terms of weight of oils in formula, it was
Rice barn oil - 600g
Olive oil - 400g
Coconut oil - 300g
Safflower oil - 100g
Sweet almond oil - 50g
Castor oil - 50g
I kept tweaking the recipe for low cleansing and high fluidity. Tried it for a few smaller batches. They came out well and were curing very well, so thought It was ok. But now they have also got some sweating (not as much as this huge batch, it is very much manageable in the sample batch).The lather was good and conditioning was really good.
But now I am struggling. I am thinking of placing some silica moisture absorbers also in each hamper (have to make them look artistic).
Do you think 4.5 tsp of salt also attracts moisture? Can Orange and Lemon essential oils also be the culprits?

 

[ResolvableOwl]

NAOH - 410.67g
Distilled water - 205.34g

water lye ratio was 2:1

Ahh ok, then you just mixed up the NaOH and water numbers in your original post. Nevermind. I had feared you have quadrupled a 3 kg recipe, so that we are talking about soap from 12 kg of oils , but now it makes sense.

The only of your oils that contributes to the “cleansing number” is coconut. As long as you keep it at/below 20%, you're safe in this respect. Hard oils don't necessarily make it difficult to have the batter fluid enough for swirl designs (good experiences with cocoa butter, palm oil, lard, and even soy wax), fluidity is a thing of the temperature control, lye concentration, and stick-blending discipline in the first place.

Salt: Have you dissolved it into the water prior to the lye, or added it into the batter at emulsion/trace? In case of solution, it shouldn't do much, but if there are still some salt crystals, they can well be the origins of “dew” from condensing air moisture and/or pull water by themselves out of the air or the soap itself. Is it purified NaCl salt, or something with additions/impurities (sea salt, unrefined rock salt, anticaking agents, iodine)?

 

[DeeAnna]

Handcrafted soap will normally sweat in high humidity conditions. I expect my soap will sweat whenever the relative humidity in my home is over 80%. When the humidity drops lower, the problem vanishes.

Salt is hygroscopic (absorbs water from the air), so when you add any salts to soap, whether they're fully dissolved or still in solid form, the soap is more likely to be sweaty in humid weather.

But the glycerin content of soap is also a factor, perhaps more so that the salt, given the relatively small amount you say you added. The glycerin made during saponification is roughly 8% by weight in a cured soap made with a cold process or hot process method, so even if you don't add salts (I do not), the soap will STILL sweat in really humid weather.

You can control this issue by not adding salts, by storing the soap in a lower humidity environment (air conditioning or dehumidifier), or by packaging the soap (after it is cured) in closed containers or wrapped in airtight plastic film. You could even go so far as to salt-out the soap. Salting-out will remove most of the glycerin and greatly reduce the chance of sweating ... but that is a lot of work and I'm not sure it's worth the trouble.

The EOs you used are not the problem.

 

[Soma]

Salt: Have you dissolved it into the water prior to the lye, or added it into the batter at emulsion/trace? In case of solution, it shouldn't do much, but if there are still some salt crystals, they can well be the origins of “dew” from condensing air moisture and/or pull water by themselves out of the air or the soap itself. Is it purified NaCl salt, or something with additions/impurities (sea salt, unrefined rock salt, anticaking agents, iodine)?

I used the common food grade salt. I dissolved the salt (and sugar) completely into distilled water before adding lye to it.
It's pouring heavily outside. I just finished shifting all the soaps into an air conditioned room. Hoping to report some good news tomorrow.
Thank you all for helping out.

You could even go so far as to salt-out the soap. Salting-out will remove most of the glycerin and greatly reduce the chance of sweating ... but that is a lot of work and I'm not sure it's worth the trouble.

One question occurred to me just now.... Does the glycerin ever evaporate out of the soap?

 

[ResolvableOwl]

Does the glycerin ever evaporate out of the soap?

No. Glycerol is non-volatile, it is a close relative to sugar and behaves similarly (except that it much more readily pulls water from the air).

 

[Soma]

Hi,
Reporting after one night of air conditioning the soaps. All moisture has vanished and soaps are firm. I was so happy in the morning. But I can't pack air conditioners with the soaps in the hampers of course. Silica moisture absorbers should do the trick. There's 12 more days of curing left. I think I will test out a hamper with moisture absorbers after that and report on the results.

You could even go so far as to salt-out the soap. Salting-out will remove most of the glycerin and greatly reduce the chance of sweating ... but that is a lot of work and I'm not sure it's worth the trouble.

You talked about salting out DeeAnna. May I have some pointers on the process please. Thanks in advance.

 

[DeeAnna]

"...You talked about salting out DeeAnna. May I have some pointers on the process please. ..."

Please see Table of contents | Soapy Stuff

A useful tip about using this forum -- I might never have seen your request if I had not thought to look at this thread today. If you put an "@" sign in front of my name, I will get a notification that you want to alert me to something. Like this -- @Soma Then it will be much more likely I will see and respond to your question.

 

[Susie]

I used to live where 90% + humidity was common. My soaps sweated all the time. I ran the ceiling fan, and eliminated the sweating. Be sure if your soaps are sweating to turn the bars over every week during cure. It ensures that you don't have wet spots on the bottom.

 

[Zany_in_CO]

Reporting after one night of air conditioning the soaps. All moisture has vanished and soaps are firm. I was so happy in the morning.

YAY! I am doing the Happy Soaper's Dance for you!

 

[linne1gi]

I live in South Florida - so pretty much high humidity all the time. A couple of years ago our AC broke. We run our air conditioning year round here - it was January, and the temperature was in the low 70's. Lovely, really, but still we have high humidity. And my soaps started to sweat - even though they were packaged - fully cured - in white boxes with windows. Sweating constantly - and they didn't stop sweating until the AC got fixed. It took about a week. Then they were fine - no problem that I could see (I was really worried about DOS, which I have experience before. Anyway, no DOS, soap was great. My suggestion - get your soaps into an air conditioned room. Or use a dehumidifier.

 

[Louis mercy]

Greetings friends and Soap makers.
Pls can anymore really help me out ..
I made a salt soap bar exactly 1day and 9hrs now it's been sweating after the cut..
I used the heat transfer method only warming my hardoils and using lyes heat...
@linne1gi @Obsidian @DeeAnna @Dawni
please pardon me if I didn't remember your handle all you other soap gurus on here Pls chime in..
First attempt at a salt bar

 

[linne1gi]

Greetings friends and Soap makers.
Pls can anymore really help me out ..
I made a salt soap bar exactly 1day and 9hrs now it's been sweating after the cut..
I used the heat transfer method only warming my hardoils and using lyes heat...
@linne1gi @Obsidian @DeeAnna @Dawni
please pardon me if I didn't remember your handle all you other soap gurus on here Pls chime in..
First attempt at a salt bar

It is probably due to humidity. I live in South Florida and when my AC broke in January, all my soaps started sweating.

 

[Obsidian]

Yes, its generally from humidity. You can try a fan to dry out the soap or if you have one, a dehumidifier

 

[Arimara]

@Louis mercy did that overheat?

 

[Louis mercy]

Yes, its generally from humidity. You can try a fan to dry out the soap or if you have one, a dehumidifier

Okay. Tnx for your input.
I had a standing fan face the Bars of soap they still are sweating... Apart from a fan or humidifier
How else can can I manage the situation..

 

[Louis mercy]

@Louis mercy did that overheat?

No I actually noticed that after the cut just few hours after ...same as the sweating

 

[linne1gi]

Okay. Tnx for your input.
I had a standing fan face the Bars of soap they still are sweating... Apart from a fan or humidifier
How else can can I manage the situation..

You actually want a “dehumidifier” not a humidifier. There’s not much you can do, hope the humidity doesn’t last long. We couldn’t live in South Florida without AC, I don’t know if that’s an option for you.