Hot car storage (oops) and no DOS?!?

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NsMar42111

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It's official, soap does what it wants!:shark:

Was cleaning out the console of my car (that I hardly ever open) and found that I had forgotten a bar of soap I was taking in to show a coworker. Plastic shrink wrapped , and I know it was in there at least 4 months , possibly 5. The temperature has been over 80, mostly near 90s, here for most of that time-which means the car is roasting hot!

And yet........no DOS! Whereas I have some made around the same time , different scent same exact ingredients (even same buckets of ingredients) but stored in a nice air conditioned house...and some DOS'd.

I think this helps confirms my theory that some of my past DOS issues are/were fragrance based, because otherwise that soap in the hot car with no air circulation around it should be orange (and it's white). Meanwhile I have lavender soap that will DOS if you look at it sideways. Wait........this means I need to test more fragrances!
 
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I have had DOS exactly twice. Once was due to old oil, and once due to lavender EO. I know, I know, I am cursing myself by saying this.

ETA: I forgot the most important part! My son left an entire shoe box full of hand made soap in his car for over 6 months in the Texas heat and humidity, and in the back window, at that! Not one developed DOS. I still have one bar of that bunch, still no DOS. Rock hard, though.
 
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NsMar42111

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Hrm, you too with the lavender? AHA! lol

Well, some of my issues were due to high humidity where I was curing. Moved curing area and that helped. I had a batch of lard that everything dos'd from (smelled and acted fine). Also discovered my vegetable peeler wasn't stainless which explaied the edges getting it. But after the humidity thing I would've thought a CAR in the direct sun in south florida would be a DOS factory!
 

madison

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I know my few lavender soap got DOS, later on I read here on the forum that DeeAnna is saying the same thing about using lavander as it oxidizes and help developing DOS.
 
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I now only make soap with lavender by special request, and I put a "use by" date on it. I tell them up front that they will DOS, and have to be thrown away.
 

cherrycoke216

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Is the high heat in car simulate some environmental heat like commercial soap factory soap cauldron? Haha...

Commercial soap in my house don't get DOS. I have tons and tons of that. ( it's my mom's gift. It's trendy thing to gift here and before retirement her career as a teacher results in tons of soap boxes. ) the old commercial soap just get some whitish flakes looking thing on top, doesn't smell funky or rancid. Maybe they superfat it at 0-1%?

And I have two DOS. One is high lard ( forget to refrigerate lard before soaping. We have subtropical weather here. Hot and humid. And I accidentally cure the batch by the window without curtains. Direct sunlight and all the humid air. 60-80% humidity most of the time. ) the other one is a local generic shortening recipe. Only DOS at the place I put another beta carotene soap on it. This is weird and funky. Doesn't smell rancid.


ETA: and by lavender which kind did you get? Lavandin ( hybrid, L. x intermedia )
or lavender angustifolia? Or Spanish lavender,also called French lavender,(Lavandula stoechas ) or Portuguese lavender ( spike, Lavendula latfolia ) the highest camphor smell one...
 

DeeAnna

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Read the labels on commercial soap. You'll most likely see one or more ingredients that are chelators or antioxidants. Even commercial soap makers have trouble with rancidity/DOS.

Yes, lavender EO becomes oxidized with age and exposure to oxygen. When that happens, the oxidized chemicals in the EO will trigger overall rancidity in fats or soap. Oxidized lavender can also trigger skin irritation if used directly on skin.

I don't have a sure-fire way to tell if lavender is oxidized, but I have sometimes noticed a faint "off" smell -- like a hint of rancid fat -- when smelling various lavender EOs. I figure if the EO smells like that, it is probably best used for potpourri or sachets, not for skin use nor for soap.
 

WeaversPort

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Hrm, you too with the lavender? AHA! lol

Well, some of my issues were due to high humidity where I was curing. Moved curing area and that helped. I had a batch of lard that everything dos'd from (smelled and acted fine). Also discovered my vegetable peeler wasn't stainless which explaied the edges getting it. But after the humidity thing I would've thought a CAR in the direct sun in south florida would be a DOS factory!

I wonder if part of what saved it; was that even though the car was in the sun, the soap was blocked from the UV and light by being in the dash?
 

WeaversPort

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Hrm, but if that was the case the soap kept out of the sunlight wouldn't dos....

LOL half tempted to toss a bar in the windshield now!

I don't remember where I read it, but there was a woman who did an informal test of her soap wrapping - one in a muslin bag and one wrapped in plastic. Both were kept in her shop, which had similar heat and sun conditions. They both developed DOS eventually, but the one wrapped in plastic in the sun was significantly worse off than the muslin wrapped soap.
 

DeeAnna

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WeaversPort

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If this is the experiment you're thinking about -- http://soapsmith.blogspot.com/2015/09/soapsmith-dos-experiment.html -- it was a test of additives (BHT and EDTA) vs no additives vs storing in muslin. No plastic wrap. But maybe there's another one out there about muslin vs plastic that I don't know about.

You're right, there was no plastic. There were two different experiments running at the same time -
1) additives + muslin vs additives & unwrapped
2) no additives + muslin vs no additives & unwrapped

Perhaps being in the dash in this case, again, helped prevent the soaps from turning. In the second test group, the muslin bag would have protected from ambiant light - if not the other elements in the shop.
 
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