bright lighting and soap turning yellow

Spice · Aug 8, 2017

I was wondering if a bright curing area with lots of light can cause a yellow on soaps. The area I have is bright because I just moved all my soap making things to an other room back in Jan. I thought it to be DOS. But my soaps have been getting ALL yellow with what looks to be oil oozing. Not sure if its glycerin. :cry:

lenarenee · Aug 8, 2017

I don't know. But if a soap is superfatted, and given that opened oils stored in lit conditions go rancid faster I think it's a possibility.

KristaY · Aug 8, 2017

Is it artificial light or sunlight? I know sunlight can affect soap but I'm not sure about artificial light. My soap curing area gets some reflected and filtered sunlight during summer mornings but it's never caused the colors to change or any seeping.

shunt2011 · Aug 8, 2017

Mine too get a bit of sunlight/filtered in the afternoon but no issues with discoloring or seeping.

BattleGnome · Aug 8, 2017

Do you have any pics?

My gut reaction is that it's summer and hot in Cali, you might be going that bit of glycerin dew that happens with the heat. No idea on the yellowing. Do you know if it's more prevalent with a certain recipe (which might narrow down a certain oil)? Maybe you have a weird additive you can rule out?

Spice · Aug 8, 2017

lenarenee said:
I don't know. But if a soap is superfatted, and given that opened oils stored in lit conditions go rancid faster I think it's a possibility.

driving me crazy, because this was not happening a year ago. I moved all stuff out into a room and not sure if its the lighting there. I have windows everywhere.

Spice · Aug 8, 2017

KristaY said:
Is it artificial light or sunlight? I know sunlight can affect soap but I'm not sure about artificial light. My soap curing area gets some reflected and filtered sunlight during summer mornings but it's never caused the colors to change or any seeping.

I have both artificial and Sunlight, I wonder if my oils are rancid. How would I know, I keep them in a closed in the dark?

Spice · Aug 8, 2017

BattleGnome said:
Do you have any pics?

My gut reaction is that it's summer and hot in Cali, you might be going that bit of glycerin dew that happens with the heat. No idea on the yellowing. Do you know if it's more prevalent with a certain recipe (which might narrow down a certain oil)? Maybe you have a weird additive you can rule out?

at first I thought maybe it was the lavender eo that I was using because it seem that it was only that soap, now I have my peppermint and all the others too. I use eo, Patchouli, Eucalyptus....etc. Here are the pic, they are the lavenders, only because they are right there, the clear on, believe it or not, I used alkanet root infused into sunflower oil. Couldn't tell by looking at it. Then the one that has one spot of DOS starting is the same oils and alkanet infused sunflower oil, this one is actually the better of all. Then the all alkanet (HP), the two others are CP, has a start of DOS, I think. It looks like it to me anyway. I am just sharking to get a bite of what is going. :shark:

soapmaker · Aug 8, 2017

My experience is that any soap with Lavender essential oil or Peppermint essential oil goes rancid and quickly. I'm not sure why but none of my other soaps do this. Light would only make this happen faster, especially natural light through windows. How would you detect rancidity? The smell! Smell in your containers of oils. Rancid oils stink. In ready made soap, bars with DOS may smell not too bad, just a little "off" for a short time but as time goes on the intended smell gets weaker and the rancidity gets stronger. The cure to this problem for me was ROE. How discouraging.

Obsidian · Aug 8, 2017

That is definitely DOS. Is the sunflower you use high oleic? Personally, I would move them out of the brightly lit room or at least hang some dark curtains.

soapmaker · Aug 8, 2017

My husband put black screen doors on my curing shelves but if there is that much light I would also hang light blocking curtains.

shunt2011 · Aug 8, 2017

I agree, it most certainly looks like DOS to me as well.

Spice · Aug 9, 2017

Thank all for the replies. I was making soap last nite, so I couldnt get on the forum till late.

As I was mixing a cocoa powder with sunflower oil, it dawn on me, I have been SF, I believe, at a high rate of oil. Instead of doing a lye discount to SF, I have been just adding extra oil, like 2 oz of sunflower oil. So now Iam wondering if that's why my soap is so full of DOS.

Obsidian · Aug 9, 2017

So your SF is set to 0 on soap calc then you just roughly guess how much extra oil you are adding? I would say that is a very possible cause of DOS. You really need to set your lye discount so you know exactly what your SF is, try 5%. That is generally enough for most soaps.

Spice · Aug 9, 2017

Obsidian said:
So your SF is set to 0 on soap calc then you just roughly guess how much extra oil you are adding? I would say that is a very possible cause of DOS. You really need to set your lye discount so you know exactly what your SF is, try 5%. That is generally enough for most soaps.

Yes, it's set to zero, and I stupidly just pour. Has to be the issue becuase i remeber it was recent, and the DOS issue is recent.

Obsidian · Aug 9, 2017

Yeah, you need to stop that lol. Not sure how big of a batch you make but for a two lb batch, 5% is only 1.60 oz. Not a very big amount and it would be easy to add way too much by eyeballing it.

penelopejane · Aug 12, 2017

Personally I would do both. Use an accurate SF and block the light from the room.

Spice · Aug 12, 2017

penelopejane said:
Personally I would do both. Use an accurate SF and block the light from the room.

since this post I made soap and cut back on the SP, I have put my soaps away from direct light too. I can tell the difference, I hope its not just wishful thinking. I wonder if DOS is the result of the SF oils?

SunRiseArts · Aug 13, 2017

This got me thinking .... could the light make the soap change depending on the fragrance? Is fragrance subjected to UV light?

penelopejane · Aug 13, 2017

Spice said:
since this post I made soap and cut back on the SP, I have put my soaps away from direct light too. I can tell the difference, I hope its not just wishful thinking. I wonder if DOS is the result of the SF oils?

I don't think so because a lot of people use 5% + SF and never have a problem with DOS. I think it is more to do with old oil, improperly stored oil and improper hygiene practices (handling the soap with unclean hands, using metal implements, improper storage etc).

bright lighting and soap turning yellow

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