Semi-Boiled soap process: Curing duration

[SoapSAZItryer]

Hi all,

A happy day to you.

I am doing a feasibility report on soap production and wanted to know what period of time soap, produced via way of hot process production (semi-boiled), must be left to cure?

I see that this is usually 3 days, but I imagine it is dependent on the oils used, the temperatures reached, the duration heated for, and the drying conditions?

Thanks for reading and look forward to engaging.

Cheers for now.
Brett.

 

[GemstonePony]

Is this for bar soap or liquid soap?

 

[SoapSAZItryer]

Hi GemstonePony,

Bar soap.

 

[DeeAnna]

You're confusing saponification time with curing time. They are two different things.

Whether you use a hot process or cold process, the time for saponification is fairly short -- a few hours for hot process and some types of cold process to several days for most typical cold process batches.

The time for curing starts after saponification is over. Most people allow a minimum of 4 to 6 weeks for curing - the time needed for the rate of weight loss to level off. For those who pay attention, they will find hot process requires a few more weeks, since it contains more water, compared with cold process. Some types of soap benefit from an even longer cure time depending on the fatty acids and additives used.

Curing increases hardness, longevity, and lather quantity and to some degree adds mildness.

 

[SoapSAZItryer]

Hi DeeAnna,

Thanks for this!

The reason I ask is I had read that with some processes, I believe it was the Colgate-Palmolive process, the production time from raw materials through to end product soap bar, saponification and 'curing' included, was 6 hours. I thought this quite incredulous, and from what you have said now I assume that they had certain inputs that provided hardness, lather quality etc without an extended curing time. That or they forwent the qualities.

Long story short, all soap should cure for between 4-6 weeks and the longer the curing the more those qualities will present themselves?

Thanks for the input.

B.

 

[DeeAnna]

Large scale commercial soap production is entirely different than small batch handcrafted soap production. Yes, commercial soap only takes hours from start to finish.

As far as your long story short ... yes, that's about it.

 

[paradisi]

Not Deanna but chiming in to say that a) the Colgate Palmolive process patent doesn't claim or mention anything about curing; b) no non-industrial soapmaker can employ that process as it requires materials, equipment and machinery they don't have.

The process is performed using liquid esters, not fats & oils, in a vacuum vessel and using fractionating columns etc.

And all it claims is speed in making a product which is vastly different to handmade soap.

The hp folks claiming hp eliminates cure because of the Colgate Palmolive process are .. misreading the process.

 

[GemstonePony]

If we're talking about adding oils and fats to lye to get handcrafted soap that is sold direct to consumers, 4-6 weeks is the minimum cure time for my fastest-curing cold-process recipes, but the soap is still way better after 3+ months. My hot-process usually takes 8+ weeks to cure, since it requires more liquid in the first place and has more water to lose. A lot of recipes take 2-3 months to really bubble well (but are extremely nice given the time), and there are some recipes that really need 6 months to a year or more to perform well. If your market is individual people, they might care about bubbles, longevity, fragrance, appearance, and how it affects their skin.

If we're talking about commercial soap that is made for manufacturer's to add to their products, then you need a factory of equipment, and your clients care primarily that they're getting soap. I'm not familiar with the laws in your country surrounding soap, but you would probably need access to a lab for testing and possibly certification, since your market will care that the soap is pure, uncontaminated soap and nothing else has been added.

 

[SoapSAZItryer]

Not Deanna but chiming in to say that a) the Colgate Palmolive process patent doesn't claim or mention anything about curing; b) no non-industrial soapmaker can employ that process as it requires materials, equipment and machinery they don't have.

The process is performed using liquid esters, not fats & oils, in a vacuum vessel and using fractionating columns etc.

And all it claims is speed in making a product which is vastly different to handmade soap.

The hp folks claiming hp eliminates cure because of the Colgate Palmolive process are .. misreading the process.

Hi,

Thanks for response.

Yes the Colgate-Palmolive does not mention anything about curing and yes, I agree that it is reserved for large scale soap production.

I do not understand what 'hp folks' means?

Thanks.

B.

If we're talking about adding oils and fats to lye to get handcrafted soap that is sold direct to consumers, 4-6 weeks is the minimum cure time for my fastest-curing cold-process recipes, but the soap is still way better after 3+ months. My hot-process usually takes 8+ weeks to cure, since it requires more liquid in the first place and has more water to lose. A lot of recipes take 2-3 months to really bubble well (but are extremely nice given the time), and there are some recipes that really need 6 months to a year or more to perform well. If your market is individual people, they might care about bubbles, longevity, fragrance, appearance, and how it affects their skin.

If we're talking about commercial soap that is made for manufacturer's to add to their products, then you need a factory of equipment, and your clients care primarily that they're getting soap. I'm not familiar with the laws in your country surrounding soap, but you would probably need access to a lab for testing and possibly certification, since your market will care that the soap is pure, uncontaminated soap and nothing else has been added.

Hi Gem,

Shot for this, appreciate the input and useful information.

Have a good one.

B.

 

[KiwiMoose]

I do not understand what 'hp folks' means?

HP folks = people who use the 'hot process' (HP) method.

 

[ResolvableOwl]

no non-industrial soapmaker can employ that process as it requires materials, equipment and machinery they don't have.

I'm not 100% d'accord with that pessimism, but more on that later/elsewhere. Anyway, thanks for pointing me to the patent – now I know that I have some patent infringement in the making (-:

 

[TheGecko]

The reason I ask is I had read that with some processes, I believe it was the Colgate-Palmolive process, the production time from raw materials through to end product soap bar, saponification and 'curing' included, was 6 hours.

Your information is not complete.

I would start with How Soap Is Made (commercially), then take a read through the Colgate-Palmolive Patent.

To save a little bit of time, the first commercial (manufacturing) processing of soap was done via the Kettle Method and patented by Heilsberg & Co G M B H 1936-38: Fats and Alkali are melted in a "kettle" (steel tank that is three stories high and hold several thousand pounds of material). Steam coils within the tank, heat the mixture. The mixture then gets salted (with real salt) to separate the soap and glycerin. The soap rises to the top, the glycerin settles to the bottom and is removed. More alkali is added to make sure no fats are left unsaponified. Then 'pitching' occurs...the soap is boiled again and water added as to separate the soap into two layers. The top layer is called "neat soap" which is 70% soap and 30% water; the bottom layer is called "nigre" and it contains most of the impurities (dirt, salt and the rest of the water that was added). The soap then gets poured into molds, where it is cooled, cut into bars, wrapped and aged.

The Continuous Process Method was patented by the Colgate Palmolive Peet Co 1942-45. It starts with a big steel column with two drains low on the side of the tank. Molten fat in pour into the top, water at 266F/130C comes from the bottom, pressured is introduced and the fats separate into 'fatty acids' and 'glycerin' and pumped out. It's called 'continuous' because it doesn't stop...as the separated components are pumped out, fat and water are pumped in. The fatty acids are then purified and mixed with alkali to form 'soap'. Added ingredients like abrasives and fragrance are also added and the hot liquid soap is then whipped to incorporate air. The soap then gets poured into molds and then put into a special freezer to harden. The soap then gets 'milled'. Logs of soap are feed through a 'noodler' then sent to a mill. The mill is a set of heavy rollers that crush and kneed the soap. As sheets of soap come off the mill, it goes through another press that forms the soap into logs, the logs are cut into bars, the bars then get put into another press that stamps the name of the company and produces many of the shapes we see today. The soap then gets wrapped and aged.

The above is pretty simplified and doesn't sound too much different than what a Hot Process soap maker would do...except separating out the glycerin for additional profitability and milling the soap. But commercial soap makers needed to get their soap to market a lot faster...and cheaper. The patent describes various experiments tried with different fats (coconut oil, palm oil, palm kernel oil, cottonseed oil, tallow, menhaden oil, olive oil, corn oil, tung oil, soya bean oil, whale oil, etc.) and adding various phosphates before or after the glycerin was removed, trying different techniques and then aging the soap between two and three months.

A lot has changed in commercial soap making over the last 80 years. The majority of the soap on the market isn't even 'soap'...it's why you will see "bath bar", "beauty bar" or if it is supposed to be a liquid soap, it's labeled as "shower gel" or "body wash"...they are more closely related to the detergent you wash your clothes or dishes with and far removed from the soaps that you or I make.

And so yes...because they aren't making real soap, they can dump their ingredients into a pot and produce a product in short amount of time.

It was so funny last night. My husband, before I started making soap, lived and breathed Tropical Dial. So last night he asked me if I have any Peach or Cantaloupe Soap in stock. I told him that I wasn't sure, but when daughter and I were cleaning out from under the sink cabinets, I found 8 bars of Tropical Dial he could use. He snarled at me and said "yuck". Then made a happy, kissy-kissy face when I returned from the garage with two bars of Peach.

 

[Sharon Patterson]

Hi DeeAnna,

Thanks for this!

The reason I ask is I had read that with some processes, I believe it was the Colgate-Palmolive process, the production time from raw materials through to end product soap bar, saponification and 'curing' included, was 6 hours. I thought this quite incredulous, and from what you have said now I assume that they had certain inputs that provided hardness, lather quality etc without an extended curing time. That or they forwent the qualities.

Long story short, all soap should cure for between 4-6 weeks and the longer the curing the more those qualities will present themselves?

Thanks for the input.

B.

I do hot process and usually allow my soaps to rest a couple of weeks. One of the other things that I do is shred older soaps, let them sit in the lye water and then add that lye water to my oil/fats. I then stick blend everything as usual. I find this actually produces a harder bar. It may be that by adding the additional soap it is actually causing a water discount in some way. Anyway, two weeks for cure time is enough to produce a very hard bar. I use this technique for all of my HP soaps.

 

[DeeAnna]

Hardness is not the only criterion people use when deciding how long to cure a soap. Your soap can be as hard as a rock at 2 weeks and still be evaporating quite a bit of water. Other issues are lather quality and longevity (not the same as hardness) and mildness to the skin.

 

[paradisi]

I'm not 100% d'accord with that pessimism, but more on that later/elsewhere. Anyway, thanks for pointing me to the patent – now I know that I have some patent infringement in the making (-:

You have a vacuum retort?

 

[ResolvableOwl]

Haha, no. But I have KOH and reasonably pure hooch at hand for transesterification. WIP.

 

[SoapSAZItryer]

HP folks = people who use the 'hot process' (HP) method.

Hey Kiwi! Thanks for that!

Your information is not complete.

I would start with How Soap Is Made (commercially), then take a read through the Colgate-Palmolive Patent.

To save a little bit of time, the first commercial (manufacturing) processing of soap was done via the Kettle Method and patented by Heilsberg & Co G M B H 1936-38: Fats and Alkali are melted in a "kettle" (steel tank that is three stories high and hold several thousand pounds of material). Steam coils within the tank, heat the mixture. The mixture then gets salted (with real salt) to separate the soap and glycerin. The soap rises to the top, the glycerin settles to the bottom and is removed. More alkali is added to make sure no fats are left unsaponified. Then 'pitching' occurs...the soap is boiled again and water added as to separate the soap into two layers. The top layer is called "neat soap" which is 70% soap and 30% water; the bottom layer is called "nigre" and it contains most of the impurities (dirt, salt and the rest of the water that was added). The soap then gets poured into molds, where it is cooled, cut into bars, wrapped and aged.

The Continuous Process Method was patented by the Colgate Palmolive Peet Co 1942-45. It starts with a big steel column with two drains low on the side of the tank. Molten fat in pour into the top, water at 266F/130C comes from the bottom, pressured is introduced and the fats separate into 'fatty acids' and 'glycerin' and pumped out. It's called 'continuous' because it doesn't stop...as the separated components are pumped out, fat and water are pumped in. The fatty acids are then purified and mixed with alkali to form 'soap'. Added ingredients like abrasives and fragrance are also added and the hot liquid soap is then whipped to incorporate air. The soap then gets poured into molds and then put into a special freezer to harden. The soap then gets 'milled'. Logs of soap are feed through a 'noodler' then sent to a mill. The mill is a set of heavy rollers that crush and kneed the soap. As sheets of soap come off the mill, it goes through another press that forms the soap into logs, the logs are cut into bars, the bars then get put into another press that stamps the name of the company and produces many of the shapes we see today. The soap then gets wrapped and aged.

The above is pretty simplified and doesn't sound too much different than what a Hot Process soap maker would do...except separating out the glycerin for additional profitability and milling the soap. But commercial soap makers needed to get their soap to market a lot faster...and cheaper. The patent describes various experiments tried with different fats (coconut oil, palm oil, palm kernel oil, cottonseed oil, tallow, menhaden oil, olive oil, corn oil, tung oil, soya bean oil, whale oil, etc.) and adding various phosphates before or after the glycerin was removed, trying different techniques and then aging the soap between two and three months.

A lot has changed in commercial soap making over the last 80 years. The majority of the soap on the market isn't even 'soap'...it's why you will see "bath bar", "beauty bar" or if it is supposed to be a liquid soap, it's labeled as "shower gel" or "body wash"...they are more closely related to the detergent you wash your clothes or dishes with and far removed from the soaps that you or I make.

And so yes...because they aren't making real soap, they can dump their ingredients into a pot and produce a product in short amount of time.

It was so funny last night. My husband, before I started making soap, lived and breathed Tropical Dial. So last night he asked me if I have any Peach or Cantaloupe Soap in stock. I told him that I wasn't sure, but when daughter and I were cleaning out from under the sink cabinets, I found 8 bars of Tropical Dial he could use. He snarled at me and said "yuck". Then made a happy, kissy-kissy face when I returned from the garage with two bars of Peach.

Hello Gecko,

Thanks for this - super-informative and enlightening! I shall follow up recommended readings, thanks for posting links!

B.

 

[TheGecko]

The "How-To" was one of the first articles I read about soap making...I found it very interesting to see how different it was. And the video of those folks in the Middle-East who still make soap the way their ancestors did for hundreds of years.

 

[Zany_in_CO]

It was so funny last night. My husband, before I started making soap, lived and breathed Tropical Dial. So last night he asked me if I have any Peach or Cantaloupe Soap in stock. I told him that I wasn't sure, but when daughter and I were cleaning out from under the sink cabinets, I found 8 bars of Tropical Dial he could use. He snarled at me and said "yuck". Then made a happy, kissy-kissy face when I returned from the garage with two bars of Peach.

I love that! Great story! Thanks for sharing!