Potato soap update

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According to this website: Understanding starch functionality
All plant starches are made up of varying proportions of amylose and amylopectin. I did not know this! I read on another website that starches break down to simple sugars in acidic conditions. That could mean that using powdered starches with vinegar as a water replacement would produce different results compared with using starch water from cooking or starch mixed with water.
Wouldn't the fatty acids in the oils take care of that either way?

Plus, we would add more lye to counteract the acid in the vinegar so it all comes back to the same effect wouldn't it?

What I am trying to say is I would think the fatty acids, regardless of the vinegar, would make the starches act basically the same?

(More of a question than a statement though.)
 
@Mobjack Bay thank you for that interesting info!

Since many of the common lye liquids - distilled water, milks, and commercial AVJ (preserved with CA) - are at least somewhat acidic, that should help starches break down into sugars, which helps boost the bubbles.

Perhaps the result is different depending on whether one mixes or dissolves the starch in the liquid before adding lye, or adds it to oils so it never gets to react with the water. Most of the time, I do dissolve CA or citrate in my water along with the sugar or starch.

I would guess that heat increases the reaction rate of breaking down the starch to sugar; I do heat my additional liquid so that the sugar/starch and CA/citrate dissolve more easily. I also stir it since that increases the dissolution rate, but I’m not sure if dissolution rate corresponds in any way to the breakdown rate.

Also, It would be interesting to know if the breakdown of starch to sugar will happen completely at a certain level of acidity, or if the breakdown rate increases with a higher level of acidity, or perhaps, over more time before a base (lye) is added to the solution.
 
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Yup. Starch granules bind to water and expand when heated. As the lye solution heats up those granules burst and the solution becomes gelatinous. Perfectly normal.

The alkali also chemically reacts with starch. A starch-alkali-water mixture will become gelatinous even at room temperature.
 
Oh gosh, I daydream about latkes. I daydream about potatoes in general, but latkes....... I like to add grated shallots to my latkes to give it more flavor. This is probably sacrilegious but I top my latkes with shallot yogurt (maast o moosir) that’s made at a local Persian market.

I also make them year-round. In fact, I just decided on what we’ll be having for dinner. 😋 We aren’t Jewish but I enjoy teaching our daughter about different food traditions and the meaning behind it.

Basically, when I’m not thinking about soap stuff, I’m thinking about food stuff. 😂🤪
I'd totally try that. I love latkes myself.
 
That is exactly what you could do. I have only done the boil water part though.

It has probably been mentioned over the years here that the residual particles of potato that remain in the water/juice will thicken up the lye water into a semi gel. The more the particles the more the gel. (In fact, that might have even been mentioned earlier in this thread years ago.)

Either way I have never noticed a bad effect on saponification though. (However, you gotta remember I strain my boiled potato water. Some particles still end up in the strained potato water but not too much and the gel is still pourable.)

Also if people extract the juice it will be full concentrate and I have no idea how that will react with the lye (i.e., gel wise). I have never done that.
Not dissimilar to when I use oat milk in my lye water - it goes gluggy too.
 
Definitely all food for thought, although my brain feels a bit gel-like right now trying to absorb it all :cool:

ETA: @RDak I was thinking in terms of what might happen if I mixed starch with vinegar before adding it to the oils. For example, this article mentions that cornstarch may not thicken a sauce if you’re also using vinegar or lemon juice because the starch breaks down into sugars. If adding starches makes nice soap because the starches are breaking down into sugars, then mixing them with an acid might be a good thing, but I always assumed it had something to do with the gel.

This next part is a definitely a sidebar:
Years ago I studied a marine polychaete worm that makes serious polysaccharide (carbohydrate) slime. Super gluggy, especially if you have a bucket full! Many marine organisms make slime, but this one is exceptional at making copious amounts. It seems possible in my current “soap anything“ brain that it might make great soap (The slime, not the polychaete). Preservation of the animals in pH buffered formaldehyde did not alter the slime, but we could dissolve it away by adding a little bleach (I assume that was due to oxidation), but we had to be careful so as not to dissolve the worm. Now I’m wondering if we could have broken the slime down with a weak acid bath. That would have been sweet!

If you are not grossed out by pictures of slime, here’s a story about similar slime from hagfish, with photos - biomaterial of the future. Hagfish Slime: Biomaterial Of The Future?
 
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Wonderful Info @AliOop @DeeAnna. The soap I made yesterday doesn't have a smooth appearance' it looks just like how the lye & rice water looked, thick gelatinous non smooth texture, I'm not happy w/ the turn out. I'll use less rice water next time, also I was practicing the Taiwan Swirl now I realize wrong recipe for that. 💫🤗 I does smell wonderful. I do want to try using Potatoes Juice' I'll start off real slow like only use 1 ounce & strain it real well, I don't want any potato bits in it.

That is exactly what you could do. I have only done the boil water part though.

It has probably been mentioned over the years here that the residual particles of potato that remain in the water/juice will thicken up the lye water into a semi gel. The more the particles the more the gel. (In fact, that might have even been mentioned earlier in this thread years ago.)

Either way I have never noticed a bad effect on saponification though. (However, you gotta remember I strain my boiled potato water. Some particles still end up in the strained potato water but not too much and the gel is still pourable.)

Also if people extract the juice it will be full concentrate and I have no idea how that will react with the lye (i.e., gel wise). I have never done that.

I't will be interesting to use Raw Potato Juice' the acidic range is similar to a lemon' another factor to take into account.
 
Definitely all food for thought, although my brain feels a bit gel-like right now trying to absorb it all :cool:

ETA: @RDak I was thinking in terms of what might happen if I mixed starch with vinegar before adding it to the oils. For example, this article mentions that cornstarch may not thicken a sauce if you’re also using vinegar or lemon juice because the starch breaks down into sugars. If adding starches makes nice soap because the starches are breaking down into sugars, then mixing them with an acid might be a good thing, but I always assumed it had something to do with the gel.

This next part is a definitely a sidebar:
Years ago I studied a marine polychaete worm that makes serious polysaccharide (carbohydrate) slime. Super gluggy, especially if you have a bucket full! Many marine organisms make slime, but this one is exceptional at making copious amounts. It seems possible in my current “soap anything“ brain that it might make great soap (The slime, not the polychaete). Preservation of the animals in pH buffered formaldehyde did not alter the slime, but we could dissolve it away by adding a little bleach (I assume that was due to oxidation), but we had to be careful so as not to dissolve the worm. Now I’m wondering if we could have broken the slime down with a weak acid bath. That would have been sweet!

If you are not grossed out by pictures of slime, here’s a story about similar slime from hagfish, with photos - biomaterial of the future. Hagfish Slime: Biomaterial Of The Future?
That’s really cool!
 
Definitely all food for thought, although my brain feels a bit gel-like right now trying to absorb it all :cool:

ETA: @RDak I was thinking in terms of what might happen if I mixed starch with vinegar before adding it to the oils. For example, this article mentions that cornstarch may not thicken a sauce if you’re also using vinegar or lemon juice because the starch breaks down into sugars. If adding starches makes nice soap because the starches are breaking down into sugars, then mixing them with an acid might be a good thing, but I always assumed it had something to do with the gel.

This next part is a definitely a sidebar:
Years ago I studied a marine polychaete worm that makes serious polysaccharide (carbohydrate) slime. Super gluggy, especially if you have a bucket full! Many marine organisms make slime, but this one is exceptional at making copious amounts. It seems possible in my current “soap anything“ brain that it might make great soap (The slime, not the polychaete). Preservation of the animals in pH buffered formaldehyde did not alter the slime, but we could dissolve it away by adding a little bleach (I assume that was due to oxidation), but we had to be careful so as not to dissolve the worm. Now I’m wondering if we could have broken the slime down with a weak acid bath. That would have been sweet!

If you are not grossed out by pictures of slime, here’s a story about similar slime from hagfish, with photos - biomaterial of the future. Hagfish Slime: Biomaterial Of The Future?
Thats interesting' maybe using raw potatoes has enough alkaline to keep it from getting gelatinous their by a having a smoother bar in texture & appearance? w/ the added benefits as mentioned before.
 
Definitely all food for thought, although my brain feels a bit gel-like right now trying to absorb it all :cool:

ETA: @RDak I was thinking in terms of what might happen if I mixed starch with vinegar before adding it to the oils. For example, this article mentions that cornstarch may not thicken a sauce if you’re also using vinegar or lemon juice because the starch breaks down into sugars. If adding starches makes nice soap because the starches are breaking down into sugars, then mixing them with an acid might be a good thing, but I always assumed it had something to do with the gel.

This next part is a definitely a sidebar:
Years ago I studied a marine polychaete worm that makes serious polysaccharide (carbohydrate) slime. Super gluggy, especially if you have a bucket full! Many marine organisms make slime, but this one is exceptional at making copious amounts. It seems possible in my current “soap anything“ brain that it might make great soap (The slime, not the polychaete). Preservation of the animals in pH buffered formaldehyde did not alter the slime, but we could dissolve it away by adding a little bleach (I assume that was due to oxidation), but we had to be careful so as not to dissolve the worm. Now I’m wondering if we could have broken the slime down with a weak acid bath. That would have been sweet!

If you are not grossed out by pictures of slime, here’s a story about similar slime from hagfish, with photos - biomaterial of the future. Hagfish Slime: Biomaterial Of The Future?
Ah gotcha......thank you!
 
Not dissimilar to when I use oat milk in my lye water - it goes gluggy too.
There's a couple of other things I do regularly for the lye water concoction:

We boil up potatoes, celery, carrots and onion all together quite a bit and I use that water also for the lye concoction. It works fine. Similar to the potato only water.

Also I make big batches of bean/veggie soup and boil the beans for an hour first. I use some of that "bean" water for the lye concoction also. Turns out fine but the water is darker. (Chick peas, not so dark.) Same basic effect as potato water.

In the end, what I am saying is you can pretty much use boiled water from all your veggie and bean boiling. All of these "waters" add to the lather. (Oh, and the onion smell does not survive the lye.)
 
I don't boil my potatoes but steam them. The water in the steaming pot still turns brownish from the potatoes. I wonder if it has any potato starch in it or not? Hrmm. Probably not I think.
 
According to this website: Understanding starch functionality
All plant starches are made up of varying proportions of amylose and amylopectin. I did not know this! I read on another website that starches break down to simple sugars in acidic conditions. That could mean that using powdered starches with vinegar as a water replacement would produce different results compared with using starch water from cooking or starch mixed with water.
Food science makes me weak in the knees.
I don't boil my potatoes but steam them. The water in the steaming pot still turns brownish from the potatoes. I wonder if it has any potato starch in it or not? Hrmm. Probably not I think.
You could add some of the steamed potatoes to your oils and blend before adding your lye solution.

200g of a Russet potato contains about 25g of carbohydrate. That is roughly the same carbohydrate equivalency of three tablespoons of powdered sugar.
 
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Food science makes me weak in the knees.

You could add some of the steamed potatoes to your oils and blend before adding your lye solution.

200g of a Russet potato contains about 25g of carbohydrate. That is roughly the same carbohydrate equivalency of three tablespoons of powdered sugar.
Awesome Info. 💫🧼

There's a couple of other things I do regularly for the lye water concoction:

We boil up potatoes, celery, carrots and onion all together quite a bit and I use that water also for the lye concoction. It works fine. Similar to the potato only water.

Also I make big batches of bean/veggie soup and boil the beans for an hour first. I use some of that "bean" water for the lye concoction also. Turns out fine but the water is darker. (Chick peas, not so dark.) Same basic effect as potato water.

In the end, what I am saying is you can pretty much use boiled water from all your veggie and bean boiling. All of these "waters" add to the lather. (Oh, and the onion smell does not survive the lye.)
Good to know. do you find you get a more bubbly bar Compared to sugar ?
 
I realise that I never posted an update on my potato soap. Of course, I had forgotten! And after all these years, I don't know anymore. So, I made another one. I used mashed potatoes as part of the water amount and added them to the melted oils before adding the lye mixture. It thickened a bit but not massively.
The soap feels very bubbly but whether it is the recipe or the mashed potatoes, I am not sure... It feels very nice anyway.
 

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Others here use boiled pasta water for their lye solution. I think Zany does. I have not tried it myself because I never boil pasta without added oil to prevent pasta from sticking together & I always use my boiled pasta water in soup (I make a lot of soup).
Hey everyone.......what do you think about using boiled pasta water???
 

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