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Hot Process Re-Melt Before Pour

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Andre

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I'm curious if anyone has ever tried to turn up the heat at the tail end of hot process, just prior to the "pour?"

The purpose would be to melt it fully before going into the mold in order to get a clean, smooth finish on the finished bar.

I'm assuming this wouldn't work with certain ingredients, such as sugars that could burn or volatile fragrances that are prone to evaporation. It also might be difficult with a crock pot - I'm thinking on the stove or a propane burner.

Assuming a simple recipe, such as a 100% olive oil bar, what would prevent it from working? Any thoughts?
 

shunt2011

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All you would be doing is cooking off the water or whatever liquid you are using therefore making it dry and more solid. It wouldn't be more liquid.
 

DeeAnna

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Shari is right. Soap doesn't always follow "common sense" rules. The thought to "add more heat => more fluid" is one of those ideas that doesn't always apply to soap.

If your soap is already in a gel state, then the soap is already in its most fluid state at that water content. Increasing the temperature won't make it more fluid for one thing. The other problem with raising the temp is the additional heating will drive off even more water from the soap to make matters worse. If the soap has cooled below its gel temperature, then, yes, you can get more fluidity by heating it until it reaches gel temperature.

If you want more fluidity, the solution is to start with and/or add water, glycerin or other water-soluble liquids. You can also add sodium lactate solution to add fluidity. Adding a superfat right before molding the soap may also help to loosen the soap somewhat. Also minimize the amount of water loss during the cook by stirring only if needed and keeping the soap pot tightly covered as much as possible.
 
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Andre

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But soap - like all solids - does have its own melting point. If it did not, there would be no such thing as melt and pour soap.
 

shunt2011

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But soap - like all solids - does have its own melting point. If it did not, there would be no such thing as melt and pour soap.

Melt and pour is made totally different with other ingredients. Please do some research on how it's made. You will see the difference between the two.
 

Andre

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Melt and pour is made totally different with other ingredients. Please do some research on how it's made. You will see the difference between the two.
Your point being that regular soap has no melting point?
 

cmzaha

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But soap - like all solids - does have its own melting point. If it did not, there would be no such thing as melt and pour soap.
Melt and Pour has additives so it can be re-melted, and is a whole different animal. HP soap will only become thicker and dryer as mentioned above. The only way to make it more fluid is adding more liquid. Adding glycerin, sorbitol, sodium lactate, or proplyene glycol will help but will change the soap, for example to much glycerin will result in a very weepy melty bar. Adding yogurt can help but you are adding in more liquid and it will take your hp bars longer to cure. Sodium Lactate is the best bet.
 

Andre

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Melt and Pour has additives so it can be re-melted, and is a whole different animal. HP soap will only become thicker and dryer as mentioned above. The only way to make it more fluid is adding more liquid. Adding glycerin, sorbitol, sodium lactate, or proplyene glycol will help but will change the soap, for example to much glycerin will result in a very weepy melty bar. Adding yogurt can help but you are adding in more liquid and it will take your hp bars longer to cure. Sodium Lactate is the best bet.
That's three people who are convinced that HP soap has no melting point.

Someone contact NASA right away.
 

nsmar4211

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You can remelt already cooled HP, but once it's melted it's melted. Turning up the heat can't melt it any further. When you are creating HP, the "melted" stage is the gel stage, at which point it cannot progress any further in terms of "melting" and the only way to make it more fluid is to add liquid, as already stated.

Insulting our intelligence is not a way to get answers.
 

Andre

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You can remelt already cooled HP, but once it's melted it's melted. Turning up the heat can't melt it any further. When you are creating HP, the "melted" stage is the gel stage, at which point it cannot progress any further in terms of "melting" and the only way to make it more fluid is to add liquid, as already stated.

Insulting our intelligence is not a way to get answers.
Can you (or anyone else) provide a source for the claim that a lipid in the gel phase cannot be melted to the liquid phase through the application of heat?

I maintain that if you can't find a source, but continue to claim it as fact, then you are claiming to have made a new discovery. In that case, my recommendation to contact NASA is merely sound advice, and not an insult at all.
 

The Efficacious Gentleman

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Try this - make some mashed potatoes. Instead of serving them, heat them until they melt. Let me know the melting point of mashed tatties. Try it with bacon, too.

Soap may well have a melting point in the general sense of the word, but what would happen to it while you heat it to that point? Would you have any reasonable soap left? What state would your soaping pot be in.

I also agree that your tone is off.
 

cmzaha

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Make some hp, turn up the heat and try melting it back down. You will have your answer. Even rebatched soap will not always remelt especially in a crock pot or double boiler. Melting in the oven will get a smoother re-melt. Do remember most of us that answered your question have been there and done that. Do try it and prove us wrong. But remember to not add in any additives when you turn up the heat
 

DeeAnna

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Your point being that regular soap has no melting point?
The point being when your hot-process soap is at gel, it has melted. You can't make it any runnier except by adding water based liquids.

It's like chocolate -- when it melts, it's melted. You can make chocolate runnier or thinner only by adding fat, not by making it hotter.

"...Can you (or anyone else) provide a source for the claim that a lipid in the gel phase cannot be melted to the liquid phase through the application of heat?..."

Okay, let's back up. Lipids? Who is discussing lipids? You yourself posted your question in the lye-based SOAP forum, "... I'm curious if anyone has ever tried to turn up the heat at the tail end of hot process, just prior to the "pour?"..."

Edit: As I acknowledge in Post 21 below, I accept that pure soap is a type of lipid. But knowing pure soap is a lipid as well as triglycerides are lipids is no more useful in answering the OP's question than saying soap is a salt and table salt is also a salt, so therefore soap and table salt should behave similarly. One has to look deeper than these very general family associations for the answers. End edit.

I can only conclude you asking a question about SOAP made with a hot process method. So the question is NOT about lipids -- we're talking about soap. They're not remotely the same. What source can YOU provide to substantiate your perception that soap IS a lipid?

Fats from which soap is made -- triglycerides -- are lipids. Soap is the salt of a fatty acid. Soap and lipids are entirely different chemicals, and they have entirely different phase diagrams. At the temperatures and pressures that a hobby or small scale soap maker can create, soap becomes thinner or thicker only by modifying the water content.

"...I maintain that if you can't find a source, but continue to claim it as fact, then you are claiming to have made a new discovery. In that case, my recommendation to contact NASA is merely sound advice, and not an insult at all...."

No, YOU need to do you homework and get your chemistry facts straightened out. After you really know what you're talking about, I will be glad to discuss this matter further.
 
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Andre

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Clearly unconvinced by by what I'd read here, I decided to go ahead and try it.

I'm not sure what I did wrong because I succeeded in melting the soap again prior to pour.

My methodology follows for the benefit of anyone wishing to replicate (even the hurt feelings crowd):

Not wanting to risk much, I decided to make a mini-batch totaling ~23 fluid ounces. My recipe was 83% Olive Oil, 17% secondary oil, with an 11% water discount and a 6% lye discount. I'm withholding the name of the secondary oil because I may add this to my product line and I'd prefer to not just give away the whole thing (particularly given the hostility here). Suffice it to say it's very similar to olive oil and should have no bearing on the success of my attempt.

With a 6% lye discount I opted to set aside 5% (by total oil weight) of my secondary oil and 1% olive oil. The aim being to achieve total saponification in the pot first, and then add the remaining 6% superfat. I was aiming for some characteristics of unreacted olive oil (but not much) and a high level of characteristics of unreacted secondary oil.

I dissolved the lye and allowed it to cool to 110 F. I brought the oils up to 110 F and combined in the pot on my electric stove. I stirred with a basic cooking whisk (I have an emulsion blender but opted not to use it). With infrared thermometer on hand I quickly got the temperature to the 230 - 240 F range, where I kept it. I stirred it aggressively with the whisk continuously for 30 minutes, at which point the liquid began to gel such that the whisk was no longer strong enough to stir it.

At this point I swapped the whisk for a solid stirrer and continued for another couple of minutes, at which point the soap reached the consistency of mashed potatoes. The temperature was still in the 230-240 range at this point. Keep in mind I had not covered the pot once this entire time, the steam was freely leaving the pot all 30+ minutes. The pot contents passed the zap test so at this point I added the 5% secondary oil and 1% olive oil. I mixed them in over the course of about two minutes, after which the contents were again a very solid mashed potato consistency.

I almost gave up on melting it at this point. 240 F is quite hot and truth the told I expected it to melt at or near that temperature. However, I decided that because I wasn't risking much in the way of ingredients I would go ahead and just get it as hot as I could. I put the top on the pot and turned the burner to max. Within minutes the soap was bubbling up and I could clearly see liquid collecting on the bottom of the pot when I lifted up the glass lid. I closed the lid and let it sit on max heat for approximately ten minutes. By the end of ten minutes it was a soap-bubbly bath of liquid.

Satisfied, I quickly stirred the contents (they would begin solidifying very fast once the lid was removed), and poured them into a nearby mold. The mold was sitting in a 20 gal stainless steel pot so that drips and splashes would not get on anything else. The liquid poured into the mold nicely, but on top of that was a thick head of bubbly foam. Once the mold was full of liquid, I went ahead and poured the foam on top of it knowing that I can trim it off later if necessary.

I had a few pieces of soap that didn't make it into the mold. As soon as they were cool enough, I gave them the float test. They all floated. I have 6 month old bars of this same recipe made with CP that do not float without several more months cure time.

Observations and Thoughts:
1 - It takes higher heat than I anticipated to melt the soap. I have a very large propane burner that gets much, much hotter than my stove that should work for a large batch if I choose to try it. My electric burner is rather high end but I do not know what temperature "max" equates to and I could not get a good reading of the pot's contents with the infrared thermometer due to the foam blocking the top.
2 - The soap appeared to darken, particularly during the max heat phase. This could be due to oxidation, which might be catalyzed by the heat. Castile soap is known to oxidize (as other soaps) which causes it to darken over a period of months in normal storage. This is only a theory.
3 - Foam is a problem. Even with the soap melted, foam and bubbles form on the surface that make pouring about as inconvenient as scooping normal HP "mashed potatoes" soap. My 20 gallon pot has a pour spout on the bottom that could mitigate this issue during a large batch. By stirring and slowly draining the contents into a large mold, foam may even be nearly eliminated.
4 - The tested soap was not nearly as "slimy" as a CP batch of the same recipe, even given a few months cure time. This, combined with the successful float test, are promising characteristics.

I'm aware much of the above is unorthodox. The batch is currently curing.
 

Andre

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Which was my point. At those temperatures, any scents or additives (milk, for example) would be utterly ruined. A theoretical process is not worth much if it is then unworkable in practice
Andre said:
I'm assuming this wouldn't work with certain ingredients, such as sugars that could burn or volatile fragrances that are prone to evaporation. It also might be difficult with a crock pot - I'm thinking on the stove or a propane burner.
So your point all along was that I was right?

Cheers then.
 

Andre

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So the question is NOT about lipids -- we're talking about soap. They're not remotely the same. What source can YOU provide to substantiate your perception that soap IS a lipid?
A little light reading for your education, Deeanna.

https://en.wikibooks.org/wiki/Structural_Biochemistry/Lipids/Soap

Wikipedia said:
Soap is a form of lipid...
Also this: http://www.dictionary.com/browse/lipid/

The Dictionary said:
any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents
Sorry to be "snarky," apparently that's how facts are interpreted here...
 

Obsidian

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Sounds more like the soap separated from excess heat, not quite the same thing as melting.
Either way, what is the point in cooking it to death when all you need to do is add a bit more water initially and some sodium lactate?
It's quite easy to make pourable HP.
 

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