Lowest superfat?

[ResolvableOwl]

Shhh! Everyone knows that ZNSC is a lye lie. But I believe @Zany_in_CO that she has optimised that recipe on point, regardless how she jovially overlooked the details of the chemistry going on. And it works well enough that I don't see the burden of proof with the practicioners (who regularly achieve impressive results by just blindly following the reicpe), but with the die-hard chemists who have to come up with an explanation why “dirty” lye (carbonate and chloride in the lye) can actually be advantageous for soapmaking.

The bicarbonate will neutralise 1.4% of the NaOH, yes. But that's on the order of weighing precision and the uncertainty of SAP values (due to botanics, geography, weather and processing). But I reckon that even the majority of SMF users couldn't tell apart soaps with ±1.4% superfat. I couldn't. And time (an important ingredient in castile soaps) is blurring the 0%SF line anyway.

 

[Zany_in_CO]

To make 0 % SF, you could just add sodium carbonate, which you could buy cheap.

Thank you for that information. I'm not so sure it's all that helpful regarding ZNSC. Dunno.

Sodium carbonate is often referred to as soda ash or washing soda. Sodium bicarbonate is popularly called baking soda. ... Sodium bicarbonate comes with sodium, acid and hydrogen. Sodium carbonate is a basic salt which is made of a strong base (NaOH) and weak acid (H2CO3). Source: Difference Between Sodium Carbonate and Sodium Bicarbonate

Um, I'm not so sure one is cheaper than the other. ??? I do know baking soda is easier to find than washing soda, depending on where you live. I have both on hand. Washing soda is more caustic than baking sode. The former is an irritant to the skin; the latter is soothing. A simple paste of baking soda relieves the pain of a bee sting.

Have you tried making ZNSC with the faux sea water made by subbing baking soda with washing soda? Just curious.

I'm not sciencesy, not at all. Simply based on my knowledge and experience over 12 years, I just built that formula on what had gone before. When I found that old file about duping sea water, I tried it and I got the result I was hoping for.

 

[Marsi]

@glendam your soap art is exquisite



thank you for your video

 

[ResolvableOwl]

@glendam your soap art is exquisite



thank you for your video

You forgot to bleep out the K-word when she calls her name

 

[glendam]

I got a chance to see the Frida soap today. Sadly it has begun to show signs of DOS. Not spots per se, but a yellowing around the edges and an initial loss of the original fragrance. I was afraid it was going to happen because it is placed by the front door, and gets sun light from a back window as well (Though filtered because their windows are tinted)

I have soap that is older than that one which is fine, so I know it is not the oils; and many other precautions were taken, (ROE, EDTA, low water, low super fat) I wish there was a way to prevent it. We live in a humid area.

I spoke to the lady who owns it, and explained what and why is happening and what will eventually happen, to see if she could place it elsewhere. She said it makes them happy to see her when they come in, and that if all of her turns brown she will buy another one to replace it.... so not much to do there, yet.

On another note, she has a Christmas themed soap slab she bought in 2019 that she keeps in a box and only takes out during Christmas time. I was surprised to see that the fragrance is still very strong (Hansel and Gretel from Lone star candle) and that the vanilla stabilizer (from Nature’s Garden) has held up. The only browning
/oxidation I saw in that soap was in a few of the embeds (the snowmen). I have noticed that white soap dough, and blue soap dough, tend to show signs of DOS faster than any other colors.

 

[Johnez]

I've moved all of my masterbatched lye into (HDPE) squeezy bottles so I can measure to 0.01g accuracy

This is a brilliant idea, I might have to borrow it. I don't know why I never thought of doing this on my own with my oils, my castor and glycerin come in nice bottles with flip caps. Is the plastic of the cap of any concern for the lye? I'm dirtying twice as many dishes with oils getting to .01 g accuracy by setting a small cup with a few grams to pipette from to add the last gram accurately.