Soap going rancid and I cannot figure out why.

[AliOop]

I really think you should determine whether the amount of ROE you are using exceeds the recommended limit, which is extremely low. If you are making small batches of soap, even a few drops of ROE could be double what is needed. That would put you into the pro-rancidity zone, where the ROE is actually causing the fats to go bad.

 

[cmzaha]

I bought the palm oil three days prior to making the soap. The palm kernel I bought two weeks prior to making the soapI( I keep the PKO refrigerated).

PKO and Palm both have a very long shelf life. Maybe try a chelator such as Sodium Gluconate instead of ROE. ROE can give issues if too much is used or if the ROE is old. I find SG worked better for me than Sodium Citrate which is another possibility.

I always purchased PKO in 35lb buckets (5 gallons), never melted it down, and had no problems with it, I just chipped away at it to get out what I needed.

 

[AliOop]

@cmzaha I agree that PKO doesn't go bad. As you know, I have one of your buckets of PKO. Despite being several years old, it has zero rancidity after being stored at room temp. Well, except for the very long drive in the back of the truck across several states, between your house and mine - I am sure it got quite hot then. And still it is just fine.

I also have never had any trouble with PKO separating or settling like PO.

 

[Zany_in_CO]

They both agree that they smell like rancid oil.

Oh my.

I also have never had any trouble with PKO separating or settling like PO.

I think that's correct. I couldn't remember for sure. Young at heart but old brain... my daughter calls me "Drain Bamaged".

 

[Marsi]

Thank you for the advice,I appreciate it. Actually this is a different room I am curing them in. We moved recently, so different house altogether. Is it okay to open windows? I always read that you want the room to be closed up where no outdoor air can get on the soap. I am so confused by it all. I will definitely keep an eye on the lye. I have had in the past where I bought some lye and it was clumoy, I threw that out and did not use it. So far the lye I use seems to okay for the most part. Thank you for the suggestion on using the teatowels. I was using parchment paper to line my racks. Maybe that is not a good idea? The room does not have any mold that I can see or smell so I don't think it would be that. That is a really good idea with increasing the lye. That might help. Thank you so much for the advice. I am just trying to figure this all out. What is interesting is that I do not see the DOS. The soaps start smelling rancid and there is no evidence of DOS usually on any of the soap that I can see. I have seen it happen a little on a couple bars, but that is like weeks after it has started smelling rancid. Usually there is no DOS, just the rancid smell.

It's sunlight that is a problem, not so much a fresh breeze from an open window
(I cure mine in a dark room with an open window that has mesh and curtain covers to help prevent dust contamination)

Edited to add:
The comments above about ROE and Sodium Gluconate/chelators are useful.
To try a simple chelator, you can add the juice of a lemon to replace some of the water (one for one replacement, lemon juice for water)
Lemon juice reacts with lye to form Sodium citrate.

I suggest you decrease the superfat to 2% allow for some experimentation.
The juice of 2 lemons will be around the limit for your batch size.
(Don't use too much lemon juice or you will get some crystals forming in your soap)

 

[Jen74]

It's sunlight that is a problem, not so much a fresh breeze from an open window
(I cure mine in a dark room with an open window that has mesh and curtain covers to help prevent dust contamination)
If your soaps are exposed to sunlight in your new room, they'll easily turn rancid.

The room has no sun as the curtains are drawn. I have a dehumidifier going and a fan blowing directly on them as they cure. What are your thoughts? Doesn't opening a window cause dust and spores from outside on them? What do you mean by mesh and curtain covers? Also, the dehumidifier does keep the room warmer in a sense, yet drier. Is that okay? Also is it okay to have a fan blowing on the soaps to help?

 

[Spice]

my apologies, I see why you're using PKO. I was thinking of using palm oil in my soap and wanted to know if its a better oil than the ones I am using, or if it adds to the soap.

 

[Marsi]

The room has no sun as the curtains are drawn. I have a dehumidifier going and a fan blowing directly on them as they cure. What are your thoughts? Doesn't opening a window cause dust and spores from outside on them? What do you mean by mesh and curtain covers?

We call them flyscreen covers here, but I used the word mesh (I don't know what you call them there) to describe a very fine mesh that is fitted to the window to exclude insects and debris (mine are coated fibreglass with very very fine holes). Over that I have a blind that is drawn.
Very little dust gets through - I do not need to sweep this room and I live in a very windy place.

My thoughts? It's generalized DOS.
You have fresh ingredients that generally don't spoil easily, distilled water and non-clumping lye, so the only two that make sense as the cause are the ROE (old or excessive, as alioop mentioned, can cause generalized DOS) and the curing environment. The curing environment has changed, so I would focus on that as a potential cause, although dropping the ROE altogether would be the first thing I would do (it is used to extend the shelf life of delicate oils, but you don't really need that with the oils you are using).

Opening a window will add a good exchange of air (not just recirculating air).

In summary, change the curing environment, drop the ROE and add a chelator
(Sodium gluconate, as suggested by cmzaha, is very good - you may want to move to this once you are comfortable with the idea of using a chelator to prevent DOS).

PS. I've updated my post above - a chelater should help and lemons are easy to come by

 

[Jen74]

We call them flyscreen covers here, but I used the word mesh (I don't know what you call them there) to describe a very fine mesh that is fitted to the window to exclude insects and debris (mine are coated fibreglass with very very fine holes). Over that I have a blind that is drawn.
Very little dust gets through - I do not need to sweep this room and I live in a very windy place.

My thoughts? It's generalized DOS.
You have fresh ingredients that generally don't spoil easily, distilled water and non-clumping lye, so the only two that make sense as the cause are the ROE (old or excessive, as alioop mentioned, can cause generalized DOS) and the curing environment. The curing environment has changed, so I would focus on that as a potential cause, although dropping the ROE altogether would be the first thing I would do (it is used to extend the shelf life of delicate oils, but you don't really need that with the oils you are using).

Opening a window will add a good exchange of air (not just recirculating air).

In summary, change the curing environment, drop the ROE and add a chelator
(Sodium gluconate, as suggested by cmzaha, is very good - you may want to move to this once you are comfortable with the idea of using a chelator to prevent DOS).

PS. I've updated my post above - a chelater should help and lemons are easy to come by

Thank you for all the suggestions, I really appreciate it. I am allergic to lemon. Could I use sodium gluconate instead? Also, how much sodium gluconate would I add? Where do I purchase this? Last question is, is it okay to keep using the dehumidifier and have a fan blowing on the soaps?

 

[AliOop]

Great point @Marsi - ROE is arguably not necessary for a recipe with just PO and PKO. A chelator like sodium gluconate would make sense here.

@Jen74 a fan and dehumidifier are ideal for curing soaps. I don’t have either for my curing soaps so I’m a little jelly.

 

[Jen74]

Great point @Marsi - ROE is arguably not necessary for a recipe with just PO and PKO. A chelator like sodium gluconate would make sense here.

@Jen74 a fan and dehumidifier are ideal for curing soaps. I don’t have either for my curing soaps so I’m a little jelly.

Thank you so much!!!. I am just trying to get this right. I honestly only make my soaps because I'm allergic to So many things. It's rough. Right now I have my one batch I made 5 weeks Ago and it's smelling already. I have no other soap I can use so will have to use it until I make the new stuff, but that will also take at least 4 weeks to cure. I will definitely try the chelator. I will have to figure out where to buy the sodium gluconate. How much are you supposed to use typically?

 

[AliOop]

Chelators can help a soap lather better in hard water, and will also reduce soap scum. So you may find that you do prefer soap with a chelator - or you may find that you don't need a chelator at all.

Honestly, unless you have really hard water, consider making a small batch, maybe 500g, with no chelator or antioxidant at all. Get that curing right away and use it as a benchmark for other test batches with a chelator.

For sodium gluconate, the typical usage rate is .5% to 1% of total batch weight. You can buy it at MakingCosmetics.com, or MakeYourOwn.Buzz. Perhaps make a small batch with that and see how it compares to the other soap without the SG.

 

[Zany_in_CO]

This whole scenario reminds me of something I went through in 2007. I lost 6 months of sales due to I didn't know what was going on with my soap. It just wasn't coming together as it should.

At that time, Mike Lawson, the Owner of Soapers Choice, was a member of Southern Soapers Yahoo Group that I was a member of. He's the one who figured it out. He offered to test samples of the two olive oils I was using. Test results proved I was using adulterated olive oil!

Slippery Business - The Trade in Adulterated Olive Oil

I believe Tom retired and the two women who now own Soapers Choice are his daughters. Maybe it's time to call in the professionals... maybe they can help figure this out. I remember how frustrated I was back then and ever so grateful when Tom came to my rescue.

Just a thought...

 

[paradisi]

Thank you so much!!!. I am just trying to get this right. I honestly only make my soaps because I'm allergic to So many things. It's rough. Right now I have my one batch I made 5 weeks Ago and it's smelling already. I have no other soap I can use so will have to use it until I make the new stuff, but that will also take at least 4 weeks to cure. I will definitely try the chelator. I will have to figure out where to buy the sodium gluconate. How much are you supposed to use typically?

Have you tried palm oil from a different source? Soapers Choice has been caught several times selling adulterated oils, incuding palm oil.

Too, I've found palm shortening goes weird faster than plain rbd.

 

[Zany_in_CO]

Soapers Choice has been caught several times selling adulterated oils, incuding palm oil.

I had no idea! If you don't mind sharing, do you have a source for that information?

 

[Marsi]

Thank you for all the suggestions, I really appreciate it. I am allergic to lemon. Could I use sodium gluconate instead? Also, how much sodium gluconate would I add? Where do I purchase this? Last question is, is it okay to keep using the dehumidifier and have a fan blowing on the soaps?

Absolutely!
Sodium Gluconate is BETTER than Sodium citrate (lemons) as a chelator
Alioop has covered the usage rates and suppliers.

if what paradisi says is true, that would explain the overall DOS issue

 

[Vicki C]

One possibility is that by putting in a few drops of ROE, rather than weighing it, you are using too much. The usage rate is really, really low - .05% - that is ½ of 1%.

Using more than the recommended amount is known to cause rancidity. Here is an article about that.

To clarify - .05% is not 1/2 of 1% - it is 1/20 of 1%, or 5 grams per 10,000 g oil. I use 0.1%, or 10 grams in every 10,000 grams of oil. But re-reading that article I see that I should probably decrease that amount - “One study looked at the antioxidant and pro-oxidant effects of ROE in soybean oil. The researchers found ROE was ineffective at 0.01% and it was pro-oxidant at 0.5%. They found ROE worked best as an antioxidant in the 0.02% to 0.05% range. (4)” (Thank you as always @DeeAnna !)

 

[AliOop]

@Vicki C thank you for catching my math error! This is exactly why i generally don’t venture far into trying to explain calculations like this. Good thing you are here to clean up my messy and incorrect attempt at that!

 

[cmzaha]

Sodium Gluconate is much better than Sodium Citrate or Lemon Juice in my opinion. Actually, I used EDTA and Sodium Gluconate at 0.5% each for a total of 1% total batch weight in all my soap batches, other than soap for my daughter. For her, I used a total of 1.2% because she has very hard well water.
I think MakeYourOwn.Buzz which is a division of Wholesalesuppliesplus was formerly Savon Citric where I used to purchase my SG.

 

[Zany_in_CO]

if what paradisi says is true, that would explain the overall DOS issue

I agree. If I were you, @Jen74 I wouldn't waste any time getting in touch with Soapers Choice... the sooner the better.

You can copy and paste the URL to this thread in an email to them. I'll be anxious to hear how they respond.