DOS?

[peachymoon]

Hi all!

I'm not sure what to make of this. I made these brine bars a couple of months ago. Last week I noticed a yellow spot on one of the bars and the others were all clear. This week, another bar has spots in two places. I have been curing these on an aluminum cookie sheet with parchment paper on top, but as far as I know, they haven't come in direct contact with any metal. There are 4 other bars with no spots.

I'm sorry, I don't have the recipe on hand right now, but I'm a new soaper so all of the ingredients were purchased within the last few months on WSP. I can update later with the recipe if it will help!

Thank you!

 

[AliOop]

Ugh, sorry to see that. I’m guessing that the parchment paper isn’t enough to protect the soap from the aluminum. The other possibility might be if they are in direct sunlight at all.

 

[shunt2011]

I agree the parchment isn't protecting the soap from the aluminum or there are a multitude of other things that can cause DOS. Sunlight, not getting good air circulation, contaminated utensils, high amount of short shelf life oils. It's a bummer when it happens.

 

[peachymoon]

@AliOop @shunt2011

Oof, ok, might be both! I'll take them off the aluminum tray, but my rack is by a window. I've been meaning to ask in here if I have to cure them in a dark spot, my soaping shelf with my supplies that I've also been curing on is in a corner next to a window. It doesn't get direct sunlight, but we do open the blinds at some point during the day. The soaps are currently on the top shelf, which sees more light when the blinds are open. Might it be enough to move them down the shelf, or should they be somewhere significantly darker? Thank you for the feedback!

 

[AliOop]

I haven't really had trouble with DOS, and I do cure mine in our guest room. I keep the blinds closed to eliminate as much sunlight as possible. Not sure if that's really necessary, but since you are having trouble, it's something to consider. Hopefully you can cut out the DOS spots and save the rest of what's left.

Also, as @shunt2011 said, you might take a look at your recipe numbers to evaluate your oils. If your combined linoleic + linolenic numbers exceed 18, you are at a greater risk of DOS, no matter how fresh those oils may be.

 

[DeeAnna]

Rancid fat is just one trigger for DOS and overall rancidity. There are many other reasons why soap becomes rancid.

Soapsmith did a test some years ago that showed her soap had MUCH less DOS if simply stored in a muslin bag compared with the same soap stored uncovered. Soapsmith' s DOS Experiment

I store my soap in a dark, cool space with low to moderate humidity. I am careful to keep soap lightly covered for protection from dust, air pollution, and UV light from the sun and room light fixtures. I either wash my hands very well or wear gloves when handling soap -- stuff on your skin can cause problems too.

 

[peachymoon]

Ok thank you, everybody! I'll definitely move them away from the window and see if I can find a better space for them.

I also didn't realize things off my hands can affect them, I'll be more mindful of that too!

 

[DeeAnna]

DOS means "dreaded orange spots" of rancidity. Wherever you see one of these rancid spots, you're also looking at a specific, often invisible bit of contamination that is quite often a bit of metal. It's a good idea to give some thought about where those bits could come from.

Some of it is in the ingredients we use -- fats, water, lye, etc. -- that have to be harvested or processed with equipment made of metal. Some of it comes directly from the soap maker -- metal from equipment and utensils, bits of dust in the air, skin, and surfaces. Anything you can do to reduce contamination from your equipment, the room air, your skin, and surfaces the soap touches is a good idea.

Overall rancidity, where most or all of the soap becomes orange colored and musty smelling, is more likely come from an ingredient that is mixed throughout the soap -- rancid fat, oxidized fragrances, water contaminated with dissolved metals, etc. -- or something that is widespread in the environment, such as air pollution or exposure to light.