Soapmaking, Spotlights6 Comments

Bonnie Bartley, Soapsmith, The Allegheny Hearth, conducted a year long experiment using the additives recommended by HSMG Conference Speaker, Dr. Kevin Dunn, Caveman chemistry, for the prevention of DOS.
Here are Bonnie’s results: One year ago, July 2008, I began an unscientific test using Dr. Dunn’s recommended additives for the prevention of DOS. On the same day, using the same identical supplies, I made two batches of my Vestal Castile Soap. The soap is 100% certified organic olive oil, distilled water and lye. Nothing else. No fragrance, no color. I did cold process, soaped between 4 & 5% superfat. To the second batch, I added .1% each of EDTA and Sodium Citrate and .05% BHT. The EDTA and Sodium Citrate was dissolved in water, the BHT dissolved in warmed oils. Both batches were brought to full gel. At all times, the test bars were kept together in identical curing and storage situations. They were cured in my soap studio for 8 weeks. One bar of each was put in muslin bags (I have always sold my bars in muslin), and one bar of each was left unwrapped. They were kept, untouched on a shelf in my office at the store. This would be the same retail environment as my soap cart. We only maintain the heat and AC during store hours, so the soap was exposed to fluxuating conditions, some very hot humid during the summer months, and 55 to 60 degree cold during the winter months.

Here are the pictures of the results:

As you will note, the two bars with the additives are sparkling white, pristine with no signs of DOS. The wrapped bar with no additives shows one small, very light DOS developing in the upper right hand corner of the bar, the unwrapped bar with no additives is almost completed covered in DOS on all sides. This did develop throughout the year, starting as typical smaller round DOS that spread to the full bar. It is also interesting to note the unwrapped, no additive bar shows great difference in shrinkage and cracking.

I have always believed that selling in muslin gives the best protection. I have had bars deteriorate on the display shelf while bars from the same batch wrapped in the muslin bags stay perfect. When I compare the bars that had no additives, the one that was unwrapped is drastically impacted by exposure to light and air. My beliefs that muslin is best for my soap have been validated.
More about Bonnie:

The Allegheny Hearth line of soap is handmade in small batches, in Bonnie’s studio located in the heart of the Allegheny Mountains. Food and cosmetic grade oils, butters, pure essential and fragrance oils are carefully blended to create a rich, emollient soap. When color is desired, Bonnie uses natural pigments, herbs, and cosmetic grade micas and colorants

The Allegheny Hearth line of body care items is also handmade from scratch. Lotions, balms, butters, powders, milk baths, tub teas, bath salts & fizzies, salt and sugar scrubs, hair serums, muscle massage balms and bubble bars are available and much, much more. In addition to the Allegheny Hearth products, Bonnie also offers the Soaps by Bonnie line. The crown jewels of Soaps by Bonnie are vegetable glycerin soaps. See her works of art here:

Bonne has been a professional soapsmith since 1979, a member of the Handcrafted Soapmaker’s Guild since 2005. Her greatest pleasure is mentoring and has an obligation to pass along methods and techniques in advancement of the craft. She feels we owe so much to the generations of soapmakers who have come before us, generously giving of their knowledge, so she is only happy to share with others.

If you are interested in her detailed instructions on creating the gemstone soaps, please email her at

Maria Gelnett – VP


  1. wow bonnie – amazing use of color in your soap! thanks for sharing the results & pics of your soap experiment!

    out of curiosity, did you try testing the ROE that Kevin also used in his experiment?


  2. Thanks for the kind remarks!

    Lori, I did not do a test using ROE. I have used ROE for many,many years in some of my soaps. I have found that it did not totally prevent DOS, they still happened ocassionally. But I did not do a side by side test like I did for these additives. Dr. Dunn’s studies seemed to indicate that ROE did add some protection but did not give the results like the EDTA, Sodium Citrate & BHT.
    He did such a professional, controlled study that I trust his results. Since these were the most conclusive in preventing DOS, I just wanted to do a comparison in real life conditions.


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