When does soap expire?

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CaliChan

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How long does soap stay good for? Does it depend on the recipe or is there a general amount of time that it will keep for.
 
Soap doesn't really expire, but it can go rancid and develop DOS: dreaded orange spots, a sign of rancidity. There are lots of variables, but it usually depends on recipe and curing conditions. Some oils like Canola, Soybean, and Grapeseed are notorious for early rancidity and should either be avoided or used in very small quantities to avoid DOS. Curing and storing soap in a cool, dry, dark place with good air circulation is helpful.
 
I think with oils that have a long shelf life, you can easily count on more than 6 months. I have some beginner bars that are about a year old right now, are gentle and still smell good. It was the most basic recipe of lard, olive, coconut and castor oil and buttermilk.
 
I use castor, grapeseed, and hemp oils in my soaps and recently found a few bars from an old batch that was a year old. I was surprised there wasn't any DOS. I plan on using this stuff for a hand soap next to the sink.
 
Depends on superfat% and oil type. A stable oil like coconut will last about 2 years even if superfatted as a really high percentage because CO oil has a long self life to begin with.
 
lard

I have been using the basic recipe with olive oil, coconut oil, & lard. Will the lard become rancid after awhile? I love the soap as does everyone that has used it.
 
I haven't used lard, but have had great success avoiding DOS with my soap recipe containing olive and coconut... I have some reallllly old soaps that are just fine to use, in fact they improve with age :D although after a while your scent can fade away. 6 months should be no problem for you.
 
Adding 10% Sunflower Oil to every batch

Hello, new member here. This is an active board. I like that.
Only made two batches of soap. First one turned out good.
60% Olive oil
10% Coconut Oil
30% Manteca (pig lard) Doesn't Manteca sound so much nicer?
5% Excess Fat

My thinking is that adding 10% Sunflower oil (to replace part of Olive) would make the bar even more stable with the Vitamin E in Sunflower oil. It's not the soap that become rancid, it's the remaining fat!
 
if you want to give it a more stable lather you should switch the percentages for coconut oil and lard, Punching that recipe into the soapcalc it was (red for low green for average)
Hardness 31
Cleansing 7
Conditioning 66
Bubbly 7
Creamy 24
Iodine 69
INS 131

but when i switched the percentages i got this

Hardness 38
Cleansing 20
Conditioning 57
Bubbly 20
Creamy 18
Iodine 60
INS 154
 
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Hello, new member here. This is an active board. I like that.
Only made two batches of soap. First one turned out good.
60% Olive oil
10% Coconut Oil
30% Manteca (pig lard) Doesn't Manteca sound so much nicer?
5% Excess Fat

My thinking is that adding 10% Sunflower oil (to replace part of Olive) would make the bar even more stable with the Vitamin E in Sunflower oil. It's not the soap that become rancid, it's the remaining fat!

What do you mean by saying it was the remaining fat that went rancid & not the soap?
I superfat at 7-8% regularly & even do some 30% superfat and have never had any of those go rancid.
 
What do you mean by saying it was the remaining fat that went rancid & not the soap?
I superfat at 7-8% regularly & even do some 30% superfat and have never had any of those go rancid.

the super fat is the oils left over that are un-saponified. Im from what ive been learning the oils themselves can go rancid and the saponified oils dont. I was informed that soaping between 5-10% was a safe range without them going rancid. and to stay away from specific oils because theyre prone to rancidity. how long have the 30% SF bars lasted you?
 
I know what super fat is. I was asking you how you knew it was the superfat that made yours rancid? I think I didn't clarify what I was asking good enough. ;)

I've got one 30% sf bar from last year & still no signs of dos.
 
Mine havent gone rancid i was just wondering when and if soap had an expiration date. Ive herd of stories of soaps that have gone bad and i was wondering if that happened after a certain amount of time and if it depended on the oils that were used. I just got a bunch of soap making supplies and was wondering if it was ok to make a large amount. There's a lot of things that i want to try and Im imagining that it is going to end up sitting in my closet for quite some time.
 
Rancidity does depend on the oils that are used. As long as your oils are not adulterated & they are not rancid or old when you put them into your soap (so try not to choose oils with short shelf life), then you should be okay. Some soapers keep their oils in the refrigerator which is supposed to help.

Also, where you cure them plays a part in it as well. Choosing an area that is cool, dry and has air flow through it will help keep the oils in your soaps from becoming rancid.

I can say that over the years of soaping I've only had a couple bars go rancid & it was because of how I was curing them in the first couple weeks.

Superfat really has nothing to do with rancidity, unless your oils are already becoming rancid.
 
I glad to see an explanation for the DOS. I have seen these on some of my bar before. The first batch I really though it was cave dust from my gear getting on it being the bars were cured where my gear was sorted and stored. The second batch I noticed on was never anywhere near the cave gear so I figured it was the soap turning. Soap still worked great though. I'm still telling people its cave dirt since the soap is dirt scented.
 
I am by no means anything close to an expert, but I just had to chime in. I am currently working my way through Scientific Soapmaking by Dr Kevin Dunn, and I just read a passage where he touched on DOS. I think it goes into more detail ( I am not finished yet) so I don't want to try and give an explanation until I do finish and understand it more, but if you are interested in the why's and how's, Overunder, I cannot recommend this book enough. It is a hard read, although Dr Dunn makes it as accessible and understandable to the lay person as he can, but in my opinion, worth the effort.
 
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Rancidity does depend on the oils that are used. As long as your oils are not adulterated & they are not rancid or old when you put them into your soap (so try not to choose oils with short shelf life), then you should be okay. Some soapers keep their oils in the refrigerator which is supposed to help..


soooo---- which oils have a short shelf life?
 
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