Tuesday, April 27, 2010

The dreaded orange spots

When I saw the acronym "DOS" in a soapmaking article I was baffled.  Being a bit of a nerd I knew perfectly well that DOS is an operating system!  So what on earth were they talking about?

I soon discovered that it stood for "Dreaded Orange Spots" orange spots about the size of a pencil eraser that can appear on soaps.  The orange spots are oxidized oils.  They can appear in soap for a number of reasons, apparently.  Some say it's because of too much superfatting.  Others that soaps made with canola and sunflower oils are more prone to it. (Just a side note: I never use canola oil.  It is hybridized rape seed which is not fit for human consumption)Still other blame storage conditions and old or rancid oils.  Still someone attributed the spots to high iodine value in the recipe (over 70).

I had never had this happening so I was a bit surprised when I discovered some of my soaps had indeed developed those spots!  The soaps are very white in colour because I added titanium dioxide to them, so the spots are very noticeable.  I have racked my brain for an explanation, but have found none.  I thought I had a good system for tracking my soaps, but I'm not entirely sure exactly which recipe this is, although I suspect it is the one with about 20% soybean oils and 23% sunflower oil and an iodine level of 71.

What I do know is that is had been stored with all my other soaps, so that is unlikely to be the culprit.  I'm still using the 25 kilos of lye so that isn't to blame.  I usually superfat my soaps by 5%, although I once made a facial soap with 10% superfat at trace with Evening primrose oil.  That soap I used up quickly, so no spots on that.  I have not had the orange spots in any other soaps, so far, so this is an interesting problem.

Apparently it is safe to use the soap.  They just look bad.  And I don't think I'm going to use it on my skin.  I have this thing about oxidized fats.  Never eat butter that has turned yellow!  I might grate it down and use it as laundry soap... or I might just throw it out!

Speaking of laundry soap, I have been meaning to make an old fashioned soap using sheep fat, just the way they did in the old days.  The sheep's fat is white, but it does smell quite a bit.  It is traditionally used in food, but I thought it could make a nice old fashioned soap.  I intend to do the laundry soap with 0% discount as there is no need for oils in laundry detergent.  Since I have just received the alkanet root I also think I'm going to colour it with that to see what colour it turns in a zero discount soap.  Should be interesting.


The photo: I love these old wire baskets. I think they are made for eggs but I'm not sure.  I have a collection of 40's, 50's and 60's kitchenalia among them the wire whisks in different sizes.

6 comments:

  1. Wow, I seriously did not know that,
    tnx for the info...
    btw...i love your blog :)

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  2. Hiya

    I've just had my second experience of DOS. The first was in a recipe I believe was too high in Hempseed Oil. This time I've been able to narrow down the two batches in question to recipes that used Palm Kernel Oil. I'm not saying that it's PKO. I'm convinced that this particular batch wasn't fresh when I received it. I'm now using Rosemary Oleoresin Extract. It discolours the oils a little but a small amount of TD makes them nice and light again.

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  3. Thank for the comments :)
    I'm also thinking it could be due to oil that is approaching it's "sell by" date although I never noticed that I was using rancid oil. I like the idea of Rosemary Oleoresin Extract, that should also be good in creams and lotions.

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  4. Do the spots smell rancid? I've only had it happen before...usually in superfatted soap that has gotten OLD. The dots I had smelled rancid to me, but my nose is pretty keen to that smell as I dislike it intensely. (I have never used canola or sunflower oils either.)
    Also, I've never had this happen in any of my soap that contain honey...I think it helps preserve the free oils, maybe.
    ~Becky

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  5. Becky, although I didn't notice a rancid smell I'm pretty sure that the spots themselves are rancid oils = not good for skin. But this has happened to fairly young soap. At least I've had older soaps that don't do this. My main suspect is old oils.

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  6. I have just started making soap recently, have enjoyed reading your posts, thank you :)

    ReplyDelete

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