I feel like I should know the answer to this, but I suppose I need a refresher. When a FO discolors due to vanilla content, is it due to air exposure, light exposure, both, or something totally different?
Discoloration in B&B products
- Thread starter Rsapienza
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It goes purple if mixed with iron! But yep, when exposed to air and light, vanillin oxidises and starts to brown.
It has a pH of about 4.3 and discolouration increases as the pH becomes more alkaline. You really notice that the colour is darker in soap and bath bombs etc
In alkaline products it can happen overnight and gets darker with time, while the process in more acidic products takes longer and discolours less.
It has a pH of about 4.3 and discolouration increases as the pH becomes more alkaline. You really notice that the colour is darker in soap and bath bombs etc
In alkaline products it can happen overnight and gets darker with time, while the process in more acidic products takes longer and discolours less.
ResolvableOwl
Notorious Lyear
Light, if at all, does only play a minor role. Air (oxygen) is the main culprit to attack vanillin in alkaline solution. Works even when you dissolve vanillia-flavoured sugar in a weak washing soda solution (no soap needed).
A systematic test would be to have four small jars with twist-off lids. Boil water with a tsp of washing soda (or baking soda). Let cool, stir in a pack of vanilla-flavoured sugar, and quickly distribute it over the four jars. Fill two to the brim and screw airtight. Place one closed and one open each, two in the light, two in the dark, for a few hours.
A systematic test would be to have four small jars with twist-off lids. Boil water with a tsp of washing soda (or baking soda). Let cool, stir in a pack of vanilla-flavoured sugar, and quickly distribute it over the four jars. Fill two to the brim and screw airtight. Place one closed and one open each, two in the light, two in the dark, for a few hours.
Bubble Agent
Well-Known Member
I wonder why I didn`t even wonder about this before, I just worked with the discoloration, but never thought to wonder about what is the trigger for the darkening! (I`m getting old and slow apparently...
)
I have two soaps that discolors, cherry - gets dark, but I use some red to make it a bit less brown and Ylang Ylang & Amber from Nurture -turns veeeery light caramel.
That being said - when you guys mentions air being the biggest culprite to the oxidation of vanillin, that would explain things. Because I cure all my soaps in a dark room/ventilated storage space (as in there is NO light coming in whatsoever) The only light is the lightbulb I turn on when I enter and turn off when I leave. And the rest of the time they are left completely in the dark.
I have always done it that way, so had it been exposure to light that triggered the oxidation then a single lighbulb turned on 4 times in a month would have apparently been enough.
)I have two soaps that discolors, cherry - gets dark, but I use some red to make it a bit less brown and Ylang Ylang & Amber from Nurture -turns veeeery light caramel.
That being said - when you guys mentions air being the biggest culprite to the oxidation of vanillin, that would explain things. Because I cure all my soaps in a dark room/ventilated storage space (as in there is NO light coming in whatsoever) The only light is the lightbulb I turn on when I enter and turn off when I leave. And the rest of the time they are left completely in the dark.
I have always done it that way, so had it been exposure to light that triggered the oxidation then a single lighbulb turned on 4 times in a month would have apparently been enough.
Light does affect it especially in creams. If they are in clear jars especially. I am currently testing this.. I can't formula due to being sick but on first week of holidays for science, we made a batch of cream with vanillin. It's split between 4 jars - two dark (violet) coloured ones and 2 clear jars.
All have been sealed. Two 1clear + 1 dark are in a sunny position on cupboard and the other two in dark cupboard. We are leaving them for a month. So far we can only check the clear ones without exposing vto air but you can see the difference already.
Things like pH, heat affect oxidisation too.
The reason I was asking is because I have made a bath bomb with a fragrance containing vanillin. The BB is uncolored and shrink wrapped. I also made some mini bath scoops with the same FO, shrink wrapped as well. These were colored. The scoops have discolored, but not the bathbombs. I do think the scoops have a small hole in the shrink wrap, where the bath bombs do not. They were both exposed to the same amount of sunlight, so am I correct to attribute this difference to the air hitting the scoops?
ResolvableOwl
Notorious Lyear
Bath bombs are not alkaline (at least not as alkaline as soap), so I wonder why they discolour at all? Wildly guessing (and with the recommendation in mind that bath bombs should be kept dry), it might just as well have something to do with air moisture, i. e. not (only) the oxygen, but also the water. I don't know.
