Cornstarch

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I just posted a thread entitled "Oatmeal," last week where I reported that bars without oatmeal powder smelled stronger, same scent same recipe.

I also don't understand how baking soda in a bath salt recipe wouldn't weaken the scent. :?
 
dieSpinne said:
soapbuddy said:
I prefer oatmeal. Orris root makes me seriously itch.

Fair enough! There are always going to be individual sensitivities and everyone should always check to make sure that their ingredients are not going to affect the intended user.

That being said, soapbuddy, are you otherwise allergic to Irises or other members of the Iris family?
Good question! I don't know. They don't grow here, so I haven't been in contact with any.
 
I also don't understand how baking soda in a bath salt recipe wouldn't weaken the scent.
I never bought that myth about baking soda being an all - smell absorber.
 
I just cut the bars and tested a little piece. It's still zappy, but from what I can tell it's not that powdery. In fact the lather is gorgeous for bars that are just one day old. Big bubbles and when you work with it it gets really silky. I only imagine it'll get better as it cures. I'll test again when the bars are less zappy and let you know how it goes.

Oh and I also checked the recipe, I had noted that I only used 4 scant tbsp for 5 pounds of oils. So maybe it'll work out after all. Only time will tell.
 
I've been pondering about cornstarch and come up with a new theory ... corstarch mixed with water turns to custard. Maybe this custard forms a barrier that stops the lye from touching the EOs. Other thickening additives (like xanthan) may have the same effect.

If that is true, cornstarch could be used to prevent seizure, for those fragrances (or other ingredients) everybody fears to use.

For it to work properly, it probably needs to be added last (at trace) and make sure you don't blend too much. If possible just use a whisk.

I've had good luck with baking soda absorbing odors. Who says it's a myth?
Of course you did, that's part of the myth :D

In my mind, all 1-cure-for-all recipes fall under the myth category. Which doesn't mean they're wrong. In fact, there's always a grain of truth to it.

I am sure baking soda has valid uses, but there's so much inconsistent information available on the topic that I can't make any sense of it.

Another piece of the myth I just stumbled upon:
Baking soda neutralizes odors chemically, rather than masking or absorbing them.
http://www.enotes.com/baking-soda-reference/baking-soda
 
Fragola said:
I've had good luck with baking soda absorbing odors. Who says it's a myth?
Of course you did, that's part of the myth :D

Huh? How can finding out from personal experience that baking soda did absorb odors be part of the myth that baking soda doesn't aborb odors?

Fragola said:
In my mind, all 1-cure-for-all recipes fall under the myth category. Which doesn't mean they're wrong. In fact, there's always a grain of truth to it.

I am sure baking soda has valid uses, but there's so much inconsistent information available on the topic that I can't make any sense of it.

I'm sure baking sode isn't a cure for all but I use it frequently for various household and personal items. It's cheap and it works which is all I care about but this is just my opinion. Perhaps I'm wrong in stating it aborbs odors. Maybe I should say it neutralizes odors. :wink:

Perhaps it isn't as effective as advertising wants people to believe. I don't know why it helps to absorb/neutralize odors. I do know that over time (1 year +), bath fizzies/bombs do lose their scent compared to bath salts. (This wasn't a deliberate experiment. They got shoved to the back and I forgot they were there. :oops: ) They also barely fizzed which tells me there is a shelf life for them. :D
 
Fragola said:
I've been pondering about cornstarch and come up with a new theory ... corstarch mixed with water turns to custard. Maybe this custard forms a barrier that stops the lye from touching the EOs. Other thickening additives (like xanthan) may have the same effect.

If that is true, cornstarch could be used to prevent seizure, for those fragrances (or other ingredients) everybody fears to use.

For it to work properly, it probably needs to be added last (at trace) and make sure you don't blend too much. If possible just use a whisk.


I've always used cornstarch as a thickening agent for sauces and gravies. I make it into a slurry and add it to hot liquid, and voila it thickens.

It does make sense though that it would thicken soap, since that's what it did to mine. I added with with clay at light trace, blended it in. The soap seemed to thicken up quickly after that to the consistency of a thinner pudding. I poured the first layer, and then after that I was spooning and smoothing layers in.
 
Hazel said:
Huh? How can finding out from personal experience that baking soda did absorb odors be part of the myth that baking soda doesn't aborb odors?

Not you finding out for yourself, but rather sharing your belief. The shared personal experience or belief of many of people is the cornerstone of any myth.

What confuses me here is the generalization. I am certain that baking soda does neutralize a certain range of odors. But I have no clue what those are.

I do know that over time (1 year +), bath fizzies/bombs do lose their scent compared to bath salts.
Probably has something to do with the recipe as a whole. This debate started with a claim that baking soda in bath salts does not weaken the scent.

Maythorn said:
I also don't understand how baking soda in a bath salt recipe wouldn't weaken the scent.

They also barely fizzed which tells me there is a shelf life for them.

From what I hear, fizzies have both baking soda and citric acid mixed in. Those probably react together over time, slowly losing their fizzle. That reaction could possibly accelerate the loss of fragrance through evaporation.

Final question remains ... would baking soda ancor scents in soap? :p
 
Hmm then I better not add cornstarch with fragrances that move fast or the soap would be so thick it would be pitiful!
 
Fragola said:
Not you finding out for yourself, but rather sharing your belief. The shared personal experience or belief of many of people is the cornerstone of any myth.
It’s not a belief. Belief is the acceptance of a concept as true which hasn’t or can’t be proven by physical means. By finding out through personal experience, it goes from belief to knowledge based upon using the product over time and discovering the results for myself. If I accepted the statement “baking soda doesn’t absorb odors” as true without ever personally trying it then that would be a belief.

I can’t state that baking soda absorbs/neutralizes all odors because I don’t know if that is true. I just know that it has worked for me for certain things. As you have stated, generalization is confusing but unfortunately many people do make generalizations out of ignorance or for propaganda purposes.

I don’t use baking soda in bath salts so my personal experience could possibly help contradict the claim that it doesn’t weaken scents over time. On the other hand, it wasn't the same FO I used in the bombs so it really doesn't contradict the claim. It could have just been a stronger FO in the salts.

My belief about the loss of fizz is the bombs had absorbed moisture which did cause them to slowly interact over time (as you mentioned), although I can’t prove it.

Fragola said:
That reaction could possibly accelerate the loss of fragrance through evaporation.

Good point.

I personally don’t believe baking soda would anchor scents in soap. But I’m not going to do an experiment to prove it. :D
 
Hmm then I better not add cornstarch with fragrances that move fast or the soap would be so thick it would be pitiful!
Quite the opposite could be true (this is only a speculation).

We agreed that cornstarch thickens a mixture, because it mixes with the water and thickens it. That could probably be compensated by slightly increasing the amount of water.

But the same process could block the lye from reacting with the fragrances, which I believe is the process that makes the soap seize. Especially if you mix in the fragrance very gently rather than blending at full speed.
 
I use corn starch in a couple of my soaps, and when I do I use a T ppo. I've never had any problems with it accelerating trace or being crumbly, or powdery. It actually adds a nice silky/satiny feel to the soap. But everyone has their own tastes, so that's where the experimentation comes in. :)
 
I'm so glad I stumbled on this post. I'm going to try a batch of tea tree soap again using corn starch and maybe the scent will stick!
 
Now that this is a few months old, I'm wondering if anyone was inspired to go and test some of this out. If so, what did you find? Any surprises?
 
I did notice one thing though, it seemed like my soap traces much faster with cornstarch in it, and I think I got a partial gel even though I soaped really cool.

Has anyone else noticed this with cornstarch?

http://www.soapmakingforum.com/forum/viewtopic.php?p=153634&sid=7ef4aae2257ec829f4cbb458d09646dd

Cornstarch mixed in water or oil becomes a non-Newtonian fluid. It will "stiffen" when aggitated quickly (as in being stickblended) but will "relax" again once it's stirred slowly. Also, cornstarch molecules unravel when heated and the long molecules will criss-cross each other forming a molecular lattice or mesh. That's how it thickens stuff. (Sauces, etc) The heat generated by the lye+oil reaction could be all it takes to make that lattice-making process occur, hence thickening the batter. That thickening would not be a saponification, but more of a "mechanical" thickening.

That same molecular lattice, is what I think helps anchor scent. The scent molecules become trapped in the lattice and in theory, the larger the scent molecules, the better they would be anchored, so any degress of scent fixation would be dependent on which scent is being used and the size of it's molecules.

Cornstarch is also a carbohydrate, a chemical sugar. I think that is what makes the soap batter prone to heating up, as any sugars in soap would do. :)
 
Not wanting to be off topic, but this post has me wondering if denatured salt would hold scent? I have used this to hold the scent in bath salts. But worry that is might have the opposite effect, since salt and vinegar work to remove scent from bottles that I recycle from essential oils.
 
Cornstarch is also a carbohydrate, a chemical sugar. I think that is what makes the soap batter prone to heating up, as any sugars in soap would do. :)

So soap does make you fat then :razz:, better stop using it :lol:.
 
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