How Much Water Evaporates?

[MorpheusPA]

Looking at some of the numbers, with water as 38% of the total oil weight (through SoapCalc while playing with it), how much eventually evaporates off?

Should I reasonably expect my soap to lose all of the water after a good cure (and drop, after all is said and done, to 72% of the total batch weight), or does some bind up and stick around?

Not that it's a critical question, but if I were to make a 1 pound mix total with lye, oils, and water, I'd like to know if I end up with 1 pound, 0.72 pounds (11.5 ounces), or somewhere in between.

Thanks!

 

[donniej]

From a laboratory standpoint, yes a fair amount of water sticks around.... but from a home soapmaker standpoint, not much water is left after 3 or 4 weeks cure time.

If you want an accurate measurement of how much water is present after curing then simply shred a bar, weight it with a good scale, cook it for hours in a toaster oven and re-weigh.

 

[IanT]

From a laboratory standpoint, yes a fair amount of water sticks around.... but from a home soapmaker standpoint, not much water is left after 3 or 4 weeks cure time.

If you want an accurate measurement of how much water is present after curing then simply shred a bar, weight it with a good scale, cook it for hours in a toaster oven and re-weigh.

do you mean a food dehydrator?

 

[gekko62]

I generally find that,after a 4 week cure a bar that started at 105g loses approx 5-7g weight.

 

[donniej]

do you mean a food dehydrator?

If you heat something in an area where the water is free to escape, you'll get it dry enough for half decent lab results... assuming low humidity.

This is just my opinion, by the way. I don't have any results to back this claim up.

 

[IanT]

true that ... I was just thinking of if the soap would melt?/ (you know im a labbie too ) lol

 

[MorpheusPA]

I generally find that,after a 4 week cure a bar that started at 105g loses approx 5-7g weight.

Cool, thanks...I can expect to lose a bit less than 4 to a bit less than 7 percent of weight at week 4. That's no big deal (not that it would be in any case, but I was curious).

Thanks to everybody else as well. I'll skip putting the soap in the toaster oven just because.

 

[bobryan1]

I've found I lose about 20-25% of the fresh cut bar after a 4 week cure. But I'm not a pro either