Cure time rule

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Science and I typically don't get along so I am no kind of science wizard but I have a great love for trig. and calc. so math isn't all that hard for me. Now saying all of that may have been over kill to say what I am about too say, but I do have a few thoughts on this and please if I am wrong or of on anything, I would be interested in hearing.

Thought 1. Is there a way to measure the amount of moisture in the soap without doing something like looking at it, poking your finger or a tooth pick in it? If there were an accurate way of measuring the moisture content then, and only then could I see it being more feasible to then try and figure out a formula. Considering how each recipe has its different oils at different percentages and different ingredients, humidity in the "curing" room, etc. there seem to be many variables that could make it difficult to come up with a formula with great accuracy. However based on a "type" of soap like you have stated "castile" you might end up doing a formula for each type. Again this is all kind of on the fly thinking right now as I write this.

Thought 2. You may end up needing to make your different recipes and finding out for yourself how long each one takes to fully cure and then keep record of those times for future use.
 
It's been my observation that soaps continue to change until you use them up. Do they have peak time? Probably. But while you use that bar the others are still aging. So again, it all depends on what your definition of "cure" is and what you are after. Like I stated before I usually start testing my bars at around 12 hours old. Sometimes sooner. Some I just love the feel of when they are brand new but of course they don't last long. I look for a balance and give them enough time to mellow out and dry enough not to be used up to fast. It also depends on if these are for your own use or for sale. Not much makes me madder than buying someone else's soap and having the damn thing wash away in a week.
 
In my experience, there is no way to simplify curing. Curing and drying are two different things and it varies by more than hard or soft oils. Im comfortable with others using some of my soaps at 8 weeks and others I wait longer, but a 120 day old Castile? No thank you. I wouldnt touch it with a stick.
 
"...Is there a way to measure the amount of moisture in the soap without doing something like looking at it, poking your finger or a tooth pick in it?..."

Sure is -- weigh the soap. You can safely assume that weight loss in soap is due to water evaporation.
 
"...Is there a way to measure the amount of moisture in the soap without doing something like looking at it, poking your finger or a tooth pick in it?..."

Sure is -- weigh the soap. You can safely assume that weight loss in soap is due to water evaporation.

So if you take that into consideration, I would say then, that when you start to see the weight plateau or not change for an extended period of time (weeks? months?) then this could be what you could consider your "cured" product then. Sure if you let this stuff sit out for 10, 20, etc. years, like all things it will just crumble. So I feel like you kind of have to find that happy medium. Of course I know nothing about this stuff, I'm just adding thoughts to the topic. I find this very interesting.:razz:
 
Yes, if the only thing that happened during the cure was water evaporation, then you could weigh your soap once a week and when it stopped losing weight it would be considered "cured". But chemical changes in soap continue well after saponification, and even after evaporation. I have read that soap is never actually in stasis and will continue to make minute changes over a very very long time but of course I cannot find the source right now, I am sorry for that. I will keep looking.

I would not find the formula for curing soaps to be accurate in my experience. I cure my soaps that are made entirely of hard oils and butters just as long as those made with softer liquid oils. Conversely, while I do cure castille soaps a very very long time, I do not cure higher olive oil soaps (50% or so) any longer than any others as long as they have other oils with them. JM2C.
 
According to this simple rule a soap made exclusively with hard oils cures in 20 days. Sure the soap will be hard enough but cured in just under 3 weeks? I'm not buying it. That doesn't give it enough time for the conditioning propeties to fully cure. It will be a better soap if you wait an additional 3-5 weeks. Its not just about soap hardness or water evaporation, the cure time also effects the gentleness and conditioning values.
 
I find (at least for me) environmental factors can have effect on my cure times. When the humidity is up, sometimes it seems to take longer ( I have no AC).
 
@ nite hawk - yep, GM soaps along with soaps made with heavy cream, buttermilk and greek yogurt fall into my "everything in between" category. They were perfectly fine after a 6-8 week cure, but still better the more they aged!
@ crazy8 - ahh, a fellow math lover! But I do love science as well and Physics has always been my forte, and I'm a weirdo that loves literature as well! I once got booed in one of my advanced physics classes in college when I was "outed" as a Monty Python fan who could quote both Edgar Allen Poe and Shakespeare, yet had never seen a single episode of Star Trek...our professor threatened to make me take the "walk of shame" from the science building to the fine arts building :( Yeah, like that was going to happen...I had the highest GPA in the class!
To get back on topic, one of the things I found with my older soaps was that they lathered better and had far more slip. My first batch was back in 2010 and while I was delighted with myself that I had actually made my very own soap; it wasn't exactly what I was looking for...it felt a little greasy to the touch and had very little slip after an 8 week cure. But it was still a pretty nice soap as it made my skin feel good and had decent lather. Three years later, this soap is rock hard and slips/lathers like a commercial soap and leaves your skin feeling incredible. The scent has faded quite a bit, but no DOS to date. While the hardness/slip factor is obviously due in part to the evaporation issue, I agree with others who mentioned that changes do continue to occur in soap long after saponification.
I DO realize that such a long cure isn't feasable to anyone looking to sell their soap and we want it to still smell nice, which is why I've strived to come up with a recipe that feels just as good after an 8 week cure. It took a lot of experimentation and many hours playing around on SoapCalc, but it was worth it!
 
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:razz:For me, a month is plenty for all of mine. I don't like to micromanage and over analyze this stuff. But that's just me.
 

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