First Soap Failure

[MarkInMd]

I've made a about a dozen batches of soap successfully. I have always used the same recipe which is a derivation of Anne's Shea Butter Supreme from Anne Watson's Smart Soapmaking.
This batch however was a little different. The plan was to make Rosemary/Peppermint soap. I introduced two new items, rosemary leaves and a green pigment powder.
I made the soap batch in my normal method and was just at the very beginning of trace when I added the essential oils (50g total per the recipe), the rosemary leaves (10g) and the pigment powder. I added the entire envelope of pigment powder (57g). As soon as I added the powder I immediately thought it was too much, but I just expected a very dark soap. However, once I started the stick blender again I knew something was wrong. I got a 3 degree rise in temperature, but no thickening of the soap. I blended and blended - WAY longer than I have ever done before - but the batch never thickened. I thought maybe it would happen as the saponification continued so I poured it into the mold anyway. Two days later I still had a LOT of fluid sitting on top of the soap. I checked the PH and it showed 7. I decided to extract the fluid and cut the bars up to see if they will dry. As you can imagine, the "soap" level mas very low since so much of the fluid had not been incorporated. The texture is very strange. I will be very interested to see what the properties of this "soap" are. I'll check the PH of the bars as well in a few days.

I wouldn't have thought that any of the additives would have had the effect it did, so I'm open to ideas about what you think went wrong.

I'm going to make another batch this weekend. No color this time.

 

[Cellador]

What kind of pigment powder did you use? It seems like a lot of powder....

 

[toxikon]

How weird! I'd suspect that using too much powdered pigment (like mica) would result in a thick, chalky soap. Not separation like that.

Are you sure you got the lye/water amount correct? No miscalculations or a faulty scale? Is it zapping at all?

For future reference, most of us use around 1/8th to 1 tsp of mica per pound of oil. 50g seems like a very high amount.

 

[DeeAnna]

I'm thinking a measurement error, scale problems, or low purity NaOH.

Soap will never have a real, true pH of 7. New soapers often get those handy pH test strips, rub them on a bar, and report the pH of their soap is 7-8. Test strips are not very accurate for soap, even if used correctly, and will indicated the pH is lower than it really is.

 

[MarkInMd]

What kind of pigment powder did you use? It seems like a lot of powder....

It was green pigment powder from Bulk Apothecary. I agree that it was way too much powder. I won’t make that mistake again. I wouldn’t think it would lead to those results though.

How weird! I'd suspect that using too much powdered pigment (like mica) would result in a thick, chalky soap. Not separation like that.

Are you sure you got the lye/water amount correct? No miscalculations or a faulty scale? Is it zapping at all?

For future reference, most of us use around 1/8th to 1 tsp of mica per pound of oil. 50g seems like a very high amount.

I would have thought the same thing, but chemistry isn’t always intuitive. No miscalculations - I was using the same recipe I always use and everything was looking great right up until I added the essential oil and color. It had a nice light trace. But no, it didn’t set up at all.

Thanks for tip on the amount of color.

I'm thinking a measurement error, scale problems, or low purity NaOH.

Soap will never have a real, true pH of 7. New soapers often get those handy pH test strips, rub them on a bar, and report the pH of their soap is 7-8. Test strips are not very accurate for soap, even if used correctly, and will indicated the pH is lower than it really is.

Anything is possible, but I am very careful measuring and didn’t appear to have any scale issues. The NaOH is the from the same container I have always used, so that is not a variable.

Thanks for all your input.

 

[The Efficacious Gentleman]

The NaOH is almost always a variable, to a greater or lesser degree - every time you open the container, or if just over time if it's not specifically stored, the lye will weaken as it takes on moisture from the air

 

[GreenDragon]

Mark,

I had exactly the same thing happen to me recently. After a lot of troubleshooting I found that my scale was inaccurate and the measurements "drifted" from day to day by 3-4%. Also, it was more accurate with weights less than 1 Lb, even though it was a 0-7 lb scale. The cumulative error was plenty to throw my batches off. This can happen with older scales or when the batteries start to get weak. I wound up replacing the scale and have not experienced this problem since.

If in doubt, grab a couple of weights around 1/2 lb, 1 lb, 3 lbs, etc that will not change (coins in a baggie work well) and take measurements right after you turn the scale on and tare it, then wait five minutes, and measure again, and again after 10 minutes. Then repeat the next day, and the next. If the weight varies by more than +/-1% or so, change the batteries and / or replace your scale. If it doesn't vary, then you have at least easily eliminated a crucial variable.

Steve

 

[earlene]

I even had a scale issue when the extension cord I had it plugged into started going haywire! The extension cord was the culprit! So if your scale plugs in you can still have problems with a scale related to the electric connection. At first I thought it was the wall outlet, then discovered it was the extension cord itself, not the wall outlet, thankfully. The extension cord is an easier fix.