Fridge or room temperature for setting?

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Dec 24, 2015
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After pouring M&P, is it preferable to let the soap harden at room temperature, or use the fridge?

I know some folk pop their molds into the fridge to help it along, but I've seen many videos of folks that leave them out at room temperature.

Is one better than another?
I don't do m&p, but i would think putting warm soap in the fridge would cause condensation and might lead to water pooling on the soap
Ive only done home-made M&P, but it always seemed happy to harden at room temp. I'm not sure its something you want to rush, and might cause sweating problems later. The only time I've heard of people put soap in the fridge to harden is if they want to prevent gelling in cold process soap, which is a non-issue in M&P.
I'm impatient when it comes to making M&P embeds so pop the mold in the fridge to help them cool and harden faster. I do put plastic wrap over the mold to prevent condensation.
I've been (mistakenly) using the fridge to rush hardening, so as an experiment, I left a loaf out overnight on the side and when I cut it this morning, it was excellent.

I guess fridge hardening is for emergencies only? From what I'm learning, patience is very definitely the name of the game here, so I'm bowing to that.

Maybe a few more attempts at various molds and soaps to see if I see a constant.

By all means share any news or updates, if you could. I've a thirst for learning! :)
When you are making M&P or using it?
When making clear soap it is recommended by the experts ( I'm not) to cool the hot processed soap as quickly as reasonably possible. Makes the soap set clearer I am told. I have made some translucent HP soap and that did seem to be the case. This was not M&P though.

When using M&P slow cooling seems to work best. But then again that's just from the stuff of the internet so it has to be true right?
Can't put anything that's not true on the internet! ;)

This is for after pouring. I made another today and it's becoming abundantly clear that setting/curing/hardening/whatever you'd like to call it is much better done slowly. At least, from what I am seeing.

Once I get a little more experienced at what I am doing, I can toy with techniques.
Supposedly, sticking a CP loaf in the fridge prevents gel phase. I don't know if you have to worry about gel phase with M&P soaps or not. I have a loaf in my fridge now, but it's a CP milk soap and I'm aiming for a specific outcome by preventing gel. We'll see if it works!
Oooo, let me know how that goes. Keen to learn all aspects of making soap, even if I haven't attempted CP yet!
I started with CP, and I'm new to it still. This milk soap is only my third batch. At this point, every batch is an experiment!
When I did MP soaps, sometimes I was impatient. You can place stuff in the fridge but youll want to do so with the small soaps (single bars to guest bar size). This is becasue it can cool more evenly and you don't have the problems with condensation if you pull it out as soon as its hardened (still slightly warm) from the fridge.

With loaf molds, this is much harder to acheive becasue the center of the loaf will still be melted while the outside is cold. This makes condensation/sweating/shrinkage more likely.

I was making an order of 140 mini soaps one time and I actually used the freezer to speed setting of the soap. I just had to check it every 5 minutes to make sure it didn't cool too much.
Hi guys, this is a VERY LONG response, as I read the initial question, as well as everyone else's posts. the fridge i find is the best luck in keeping clear soap clear. freezer and room temp not always. keep in mind that adding colours and scents to your clear base, will also change its compositions... sometimes the scent you really want, just cannot be added to clear base without clouding it.
The question on whether to cool soap rapidly or slowly depends on what the soap is made out of, and what your are hoping to end up with. I do it all fairly competently, though I am certainly no visionary on the creative artistic side, like some people.
1. Cold opaque soap with vibrant colours you will often want to cool very quickly depending on what you use for colour. Some colours will start out vibrant and get dull or neutral if allowed to or wrapped and encouraged to gell. Each colour is different. Some synthetics will not change no matter what, some clays will also remain the same. You need to look at each product you use.
1. Cold opaque goat's or other milk, honey or sugary soaps you must cool quickly, as the heat of saponification will burn and scorch the sugars giving them a burnt/amonia terrible smell, and will darken your soap to brown.
-My first attempt at making goat's milk soap was an insult to all goat-kind, any creature that happens to make milk, and I believe I hurt mother nature's feelings all around.
I was at work with a partner (we are flight EMTs in northern alberta) and after finding some lye, we got to experimenting. the first batch actually turned out into something half decent, being white with half the bactch mixed with cocoa powder and swirled. Seeing this, some female colleagues asked if we could make goats milk bars as well. without reading... I guessed! I hot processed a batch of goats milk soap and it stunk up the entire ambulance bay and sleeping quarters! it turned hard brown and crusty, and we had to dispose of it behind the building! So, I read.
with cold pour milk or sugars or honey, you want to freeze the goats milk prior to mixing with lye to start, and you want to place that bowl outside in the winter as you blend your ingredients (or else a second larger bowl full of ice) and keep that lye and milk as COLD as possible! Once you mix in your oils and FO (most EO are destroyed by lye for those wishing to be all natural), stickblend to trace ASAP, pour in mold, and get outside in the snow, or else directly into your deep freezer. If you are very lucky, or you use titanium dioxide, you will wind up with a lovely white or just slightly off-white mild goat's milk soap. If you have trouble keeping things cool or get delayed pouring into the mold, or if you use just the refridgerator, you will wind up with a pale yellow to a dark orange/ light brown bar. These bars are just as mild and useable as the pure white bars, it is purely an aesthetic preference. Also, milk soaps may require being cured in the friedge veggie drawer or in a cool ventilated place as part of the leftover product of milk being pulverized by lye, is ammonia. This is usually in harmless levels and can be used, but it smells noticeably 'off'. an extra week or two ventilating, and the bars will harden, air off the undesirable aerosols, leaving you with a product you can enjoy.
3. HOT PROCESS. This is my goto choice with soap. I am simply too impatient to wait 4-6 weeks for a batch to finish curing to finally use it! I make a batch of soap, and I want to be able to test it within and hour or two! Hot process is the way you want to go if you wish to keep things 100% natural too, as all the lye is used by the time you are done, and this means you can add pure essential oils and herbs and other super fats and luxuries without any worry that they will be devoured by the lye. what ever colours you put in, is the colour you wind up with as 'gel' phase has been started and finished as you cook your batch in your slow cooker. The consistency when complete and ready to be scooped into molds is equal to that of starchy mashed potatoes, rather than the cream or pudding texture for those used to cold processing. Color options are generally more crude than with cold pours where very fine lines and swirls are possible. so, if you are making art for your bathroom as decoration, cold process is where precision and fine details can be achieved. with hot process, you CAN still do a fair bit using simple food colouring or any media you like since theres no lye. you can make layered and marbled patterns easily. What many people don't know (including a supply shop I goto where they teach classes), is that you CAN get some pretty fine lines and patterns. for example, if you use a bread pan (since the lye is gone, you can use any container you want) and you layer the botom black and the top white (or three or four layers of anything you wish) and you bend a wire clothes hanger to the same lengths or widths, you can 'barrel-roll' or up/down line, or zigag etc any pattern you choose, and when you cut the individual bars later, you will be remarkably supprised at the thin, fine lines and details. (* note, using the upper limit of water in your recipe or slightly increasing it (SLIGHTLY) will facilitate even more details. this just requires longer for the soap bars to dry harder. Mine are noticeably soft the first bar of a batch I used, but by the time i get around to the last few bars, they have hardened much more. or, make 2 batches. set one aside to harden as you use the other.
**TRANSPARENT, MELT&POUR**. detergents vs soaps.
if you buy plain transparent/translucent stock from the soap store, read the instructions or ask the store owner, as more times than not, these pre-made melt and pour stocks are not actually soaps, but in fact 'detergents'. for every day showering cleaning, the differences are slight, but that is where the similarities end. Different detergents will have different ingredients that once microwaved, scented and coloured, will react differently from each other. in general, the faster you can solidify the molecules that make up the detergents in a random state, the more clear they will be. However, each formula is made differently by each manufacturer, as such each will have different properties that is beyond what would be competent to explain here.
I make my own clear soaps, both for plain 'glycerine' soap, as well as for stock for my wife and kids to create with. like most of my soaps, the recipes vary batch to batch depending on what i have handy, what requests I have, or whatever I have read recently that influences my mind. As I am writing this long essay I doubt anyone of yous will actually read, I have just completed a large batch of clear soap, that may or may not turn out as I want *more on that at the end*. So, I poured 1 third into an empty tenderflake lard bucket and set it in my fridge, I filled up a pringles bottle for a round log, and set that on my shower windowsill, and I poured the rest into a 1 gallon plastic ice-cream bucket and set it outside in my unheated porch sitting at about -15 degrees Celcius (F and C equal at -32, water freezes at 0 degrees C. so halfway between -32F and whatever water freezes at in Fahrenheit. ) I tested my batch by spoonful in frozen cups, tweaking the batch until i was reasonably satisfied before . If you guys wish, I will tell you how things went tomorrow. The 'official' cutoff for soap to have 'clear' status, is you must be able to read size 12 text through a 1/4 inch slice. I usually aim for 3/4. These clear bars, once done, will shrink and warp as the alcohol in them evaporates over several weeks and possibly months becoming even more transparent! so even if your clear soap does not please you at first, wait! One of my worst batches ever, came out like milk. so i left it at a friend's house in his basement and forgot about them. over a year later, his wife found them. To my amazement! they had turned clear as yellow glass and were as hard as jolly ranchers candy! And I would have thrown them or reprocessed had I remembered to!
Anyways to answer the original question, the most reliable book I bought and learned from stated that cooling clear soap ASAP is the way to go. I have found however, that the batches I placed in the fridge for lack of room in my freezer, actually turned out much more transparent, contrary to what I had read... tonight, will be the first night I actually allow a log to solidify at room temp.
for anyone interested in making their own transparent soap from scratch, here are two recipes that have worked flawlessly for me at times... these exact same recipes have also failed me once or twice (ambient temps, arbitrary tweaks, barometer pressure, or the patience it requires at the end where you must keep cold glasses in the freezer that you may take tablespoons of your clear goop and solidify repeated samples until you finally get one that is perfect or near perfectly clear..... THEN, if you over shoot it... it gets better, better, better, perfect, worse, worse... there's no recovering it unless the mistake you made was excess alcohol, which can be evaporated off. **isopropyl alcohol will only every yield translucent soap. Ethyl alcohol or ethanol is absolutely necessary to achieve true clarity.
recipe 1

For the size of fat batch that you are using, we recommend that you use approximately 612 to 917 milliliters of liquid.
***because i know i am proceeding beyond this to clear soap, i want minimal water as it is a solvent. so 620 grams
WARNING: Always add your solid form lye, sodium hydroxide or potassium hydroxide, to the liquid. If the liquid were added to the solid form lye a violent reaction could result. This means you could have a "volcano" erupt out of your container.

Fats & Oils
Fat Amount
(grams) % in
Canola Oil 1263 51.64
Castor Oil 251 10.26
Coconut Oil 450 18.40
Lard 482 19.71
Total Weight 2446

Lye Table (NaOH)
% excess fat Lye Amount
0 354.77 *** because excess fat prevents clarity, i used 354.0 grams

1 351.23
2 347.68
3 344.13
4 340.58
5 337.03
6 333.49
7 329.94
8 326.39
9 322.84
10 319.30
0% to 4% excess fat range: Proceed with caution! We do not recommend this unless actual saponification values are known and used.
after this easy hot process soap is done, the real work starts, but its worth it!!!! (usually)

the solvents i calculated:
ethanol 980 grams (i wound up using 1500grams (mls or cc same thing) because is was short on glycerine.
glycerine 400 grams (I would likely undercut that even if not short) I have about 50 grams only :/
sucrose 205-307 grams white sugar. i used 405 grams total before getting the clarity i wanted.

slow cook /crock pot on low heat. scrap surface until clear. once clear, leave for 20 min/ half hour before starting
the process of taking spoonful samples into freezer cold glasses to check clarity.
its work! do not exceed sugar or glycerine by too much as it is impossible to reverse.
remember, your final product will gain hardness and clarity in the weeks to come.

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