Newbie: Lye temperature reccomendations?

[Fid Tanada]

"...What i don't get is like when they "make up the rest" of the liquid with milk or aloe (like examples given above). If the rest of the liquid (say aloe) doesnt have lye in it, wouldn't the concentration of lye be even lower since you are "diluting" it with more liquid (the aloe)..."

Yes, that is correct. You've gotten good explanations from three competent soap makers, so hopefully you're making sense of it all now!

"...OR is that where the water discounting comes into play?..."

Not really. Water discounting isn't directly related to the use of masterbatched lye. Here is what the terms "water discount" and "full water" mean to most people most of the time --

"Full water" means a soap recipe that uses an NaOH solution at roughly 28% NaOH concentration. This 28% concentration is supposedly the "normal" amount of water for making soap (although it's really not). If you use a more concentrated lye solution than that -- say 33% lye concentration for example -- then you are "water discounting" or using "less than full water" to make your soap.

It makes no difference how you make the lye solution -- you can make it by mixing water and solid NaOH or you can make it from a masterbatched lye solution. The essential point is "full water" is about 28% lye concentration and "discounted water" is a more concentrated lye solution.

I personally think terms "water discount" and "full water" have no truly useful purpose, but they are firmly part of soap making lingo, so I live with 'em.

Hello,

Is there any risk of food contamination if I place my cold process soap inside the fridge? I live in a tropical country, and gelling is never a problem due to high temp. However, I see that this could be a problem if I decide to make milk soap. Thanks in advance!

Fid

 

[dixiedragon]

This is an old post, so you may want to start a new thread, b/c people might respond to the original post vs responding to your new question.

I personally worry about having some kind of accident and spilling soap all over my fridge, so I don't put freshly poured soap in the fridge. It's possible that your soap could give off enough fragrances to make some items taste or smell a bit like the FO.

My suggestion would be to make an ice pack with 1 part rubbing alcohol and 3 parts water. (some people recommend 4 parts water.) double back this this in ziplock bags. If you have a food sealer, those bags are even better. Lay them flat in your freezer and let them get nice and frozen. When you make soap, put 1 underneath and 1 on top.

 

[DeeAnna]

I personally am not comfortable with the idea for the same reasons Dixie has given. Once upon a time, I worked in a chemistry lab, and we were taught that food and lab chemicals do not mix, so only food in the lunch room refrigerator. We had another fridge in the actual lab for samples and chemicals that had to be kept cool -- and food was never stored in that fridge. I think this rule makes even more sense in my home.

I also do not see the point of putting hot soap in the fridge or freezer, because chilling something in not-moving air is very inefficient, even if the air is cold. If I need to cool soap, I will set the soap mold on some blocks or food cans so the bottom is exposed to the air, and then put a fan on the soap so air circulates all around the mold. That cools the soap efficiently and quickly.

PS: And Dixie is right about asking your question in a new thread. More people will read it and answer and you might get better advice that way.

 

[DeeAnna]

In re-reading this thread, I want to add something to my post #5 just for the record --

The OP wrote: "...everything i have read is have the oil be the same(ish) temperature as the lye solution. ..."

I replied: There are a lot of ideas that seem to make "common sense", but actually make soaping more complicated than it needs to be. This rule is one of them. It might have been created to keep beginning soapers out of major trouble, but then it took on a life of its own....

There is a safety issue that I didn't mention in that post and I want to set the record straight. A big difference in temperature between the lye and the fat can sometimes be dangerous.

IF the fats for making soap are heated up to or above the simmering point of water (about 180+ degrees F or 80+ degrees C) AND the lye is quite bit cooler (say about room temperature to lukewarm), THEN when you pour cool lye solution into hot fat, the mixture is likely to spatter or boil over. At worst, this can cause serious heat and chemical burns to a person's face, eyes, and hands. At the least, it will create a huge mess that is tough to clean up.

What happens is the cool lye solution instantly heats up as it falls through the hot fat. That rapid heating causes the water in the lye solution to boil, quickly turning the water into steam. The steam expands and shoots back up through the fat, causing hot fat and lye to spray out of the container. This is the same spattering action that you get when you fry or saute watery food, only much more dangerous.

How to avoid this problem? In a nutshell, make sure the fat is the same temperature or cooler than the lye solution.

For everyday normal soap making, do a quick check of the fat temperature with your hand. If the fat is lukewarm to quite warm to your skin, but not burning hot, then this problem is not a problem -- the fat isn't nearly hot enough to create steam. The lye solution can be any temperature from ice cube cold to blistering hot (some people melt their fats with hot lye solution) and that's okay.

Some methods of soaping require your ingredients to be heated to higher temperatures than usual. Examples include the high temperature hot process method and cold process soap making using fatty acids or beeswax. In these situations, you may be working with ingredients that are at or above that 180 F / 80 C danger zone. In this case, you can't do a "hand test" so check the temps of the fat and lye solution with a thermometer before mixing them together. The fat should be at the same temperature or slightly cooler than the lye solution before you proceed.

 

[Soapmaker123]

My procedure is to mix the dry lye in a 60-gallon tank into the water, a 50-pound dry-lye sack in one go.

The sack is never exactly 50 pounds, so I must 'trim' the solution with a bit of extra water or extra lye to standardize my lye solution.

The newly-made lye solution becomes hot; so I let it sit overnight for soap making the next day.

The tank of solution cools down, but, the next morning, it can still be a bit hot or somewhat cold . . . depending on the season and building temperature. There will be pure-water condensation on the top lid of the lye tank which must be accounted for and shaken back into the lye solution so that the concentration is correct.

My base oil tank is electrically heated and regulated with a thermostat,

So if the lye solution is a bit cold, I can run the oil temperature a bit warmer, and the converse.

If you don't have time to let your lye solution cool down sufficiently, you can directly substitute by weight ice for some of your liquid water.

 

[dixiedragon]

Wow, I learned a lot! Thanks Deanna.

 

[seaberry]

I’m fairly new to soaping...I did melt and pour for awhile and recently tried cold process. I’ve been adding lye to ice instead of waster and kind of like it.

 

[DeeAnna]

You can get the lye solution too cold, just so you know, so using all ice to make the lye solution isn't a panacea.

First off, cooler temps reduce the solubility of NaOH in water. The NaOH in a 50% NaOH solution will start to precipitate out when the solution cools below about 55 F / 15 C or so. A 30% NaOH solution will start to precipitate at about 32 F / 0 C. This may or may not be an issue for you, but it's good to be aware.

Second thing is many people want the soap batter temp to start at 100-110 F / 38-45 C. If your lye solution is very cold, that means you may have to warm the fats more to get the batter temperature sufficiently warm enough. This depends on your soaping style and also on whether your recipe has a large proportion of solid fats (especially lard, tallow, palm, or butters) that need warmer temps to fully melt.

 

[seaberry]

You can get the lye solution too cold, just so you know, so using all ice to make the lye solution isn't a panacea.

First off, cooler temps reduce the solubility of NaOH in water. The NaOH in a 50% NaOH solution will start to precipitate out when the solution cools below about 55 F / 15 C or so. A 30% NaOH solution will start to precipitate at about 32 F / 0 C. This may or may not be an issue for you, but it's good to be aware.

Second thing is many people want the soap batter temp to start at 100-110 F / 38-45 C. If your lye solution is very cold, that means you may have to warm the fats more to get the batter temperature sufficiently warm enough. This depends on your soaping style and also on whether your recipe has a large proportion of solid fats (especially lard, tallow, palm, or butters) that need warmer temps to fully melt.

Thank you for sharing this! I’ve only attempted 2 bars so far. I have worked with melt and pour and wanted to go to the next level. It’s a beautiful art! I’m already learning a lot from all of you

 

[Fid Tanada]

This is an old post, so you may want to start a new thread, b/c people might respond to the original post vs responding to your new question.

I personally worry about having some kind of accident and spilling soap all over my fridge, so I don't put freshly poured soap in the fridge. It's possible that your soap could give off enough fragrances to make some items taste or smell a bit like the FO.

My suggestion would be to make an ice pack with 1 part rubbing alcohol and 3 parts water. (some people recommend 4 parts water.) double back this this in ziplock bags. If you have a food sealer, those bags are even better. Lay them flat in your freezer and let them get nice and frozen. When you make soap, put 1 underneath and 1 on top.

Thank you so much!! This was very, very helpful. I made my first cold process soap with coconut milk today, and while I placed it inside the fridge (I didnt notice any foul smell), the surface cracked a bit. So, I decided to put it in the freezer and just take it out to room temp the next day.

Fid