Weighing Ingredients the Kevin M Dunn Way

[Sandiebrown65]

Hi Everyone,
I am a fairly new soaper and am currently reading Scientific Soapmaking by Kevin M Dunn. I just have a question about the way he wants his readers to weigh things. Now, I did chemistry 101 at Uni and I don't remember weighing out things like he describes. I sometimes get so confused about how he wants me to weight something that I end up just putting the book down and walking away. Does anyone else have trouble understanding what he is asking? Do you all follow his method for weighing out ingredients? I am trying to masterbatch and got completely lost in his description for measuring out the oils. Am I destined to never make a batch of Ducks Delight?

 

[TheGecko]

Never read his book so I couldn’t tell you. However…ingredients should be weighed and not measured, and by ‘measured’ I mean volume. Probably not as big of a deal for those on the other side of the pond and down under since a kitchen scale is stand equipment, while us folks in the wilds of the States are still banging our measuring cups like savages. And of course, grams are the preferred method, but as previously noted, I am a savage and uses ounces…abet to the hundredth of an ounce. And I’m afraid that I don’t weigh my additives and use teaspoon and tablespoon instead because I find it easier than trying to weigh one or two of them. Which BTW, is a lot for me to do in the first place since I grew up with recipes that contained such measurements as ‘pinch, smidgen, dash, generous, palmful, thumb’s amount, etc’. Someone once asked me to write out the recipe for my Macaroni Salad and I couldn’t because I never actually measured anything…the best I could do was give her a list or ingredients and which her the best.

 

[DeeAnna]

It's possible you were never taught analytical weighing methods, depending on the type of introductory chemistry class(es) you took -- intro to chem for chemistry majors is different than intro to chem for history majors.

Precise measuring is critical in analytical chemistry where accuracy is super important and you're working with small samples -- sometimes less than a gram. In soap making, the bar is set a lot lower. Soap making is considerably less accurate than analytical chem and we're working with large amounts of ingredients, so less accurate weighing methods are sufficient.

If you are making soap and don't have a a great interest in learning analytical weighing methods ... then don't worry about it. Just work as accurately as you can.

If you ever get into things like perfumery or cosmetic formulation, it's probably best that you should learn.

 

[Zing]

You've already heard from two expert soapers here. I'll just add my experience if it's helpful. And I have not read Dunn but I gather from this forum that he's respected.

In short, if you have a good food scale, and you weigh all ingredients then you are all set! In my first year, I measured ingredient weights in ounces. But as an undergrad chemistry major, I knew that grams were more precise so I switched to grams. My scale's smallest unit of measure is whole grams. The compulsive part of me wishes my scale had decimal grams when recipes call for 20.59 grams -- but I just round up or down. Even to this day, I have to actively remind myself that I used to use imprecise ounces -- and still ended up with soap!

The key thing is to make sure you use up all your lye. You want every lye particle to marry an oil particle. Unmarried, single lye particles are bad. However, it is fine and desirable to have unmarried, single oil particles. Your recipes will include a "superfat" which means you purposely add extra oil to ensure there are no leftover unmarried, single lye particles. How's that for a scientific explanation?

Also, if I might add some unsolicited advice: Get some small batches under your belt before you do a masterbatch. Get to know what combination of oils you like. Once you've tweaked your recipe to your satisfaction, then you can masterbatch. It took me a year to refine my main recipe.

Best wishes. Keep us posted and we like pictures!

 

[Sandiebrown65]

It's possible you were never taught analytical weighing methods, depending on the type of introductory chemistry class(es) you took -- intro to chem for chemistry majors is different than intro to chem for history majors.

This is true! I did an animal science degree. I also worked in a wet lab for most of my life and we just weighed things on an analytical balance.