The Science of Soap

The owner and founder of Dorset Daughters, Carrie Williams, explains the fascinating craft of artisan soapmaking.


On a quiet country road in Dorset, a beautiful 19th-century farmhouse stands in the foreground of a steep, treelined hill. Inside, the owner and founder of Dorset Daughters, Carrie Williams, is busy preparing a fresh batch of artisan, handmade soap in her workshop. Looking down at a recently-opened soap mold, she maintains the focused, exacting comportment of a world-class scientist as she inspects its contents. It’s been two decades since Williams began making soap, but she still retains the same intense passion that originally motivated her to begin pursuing her chosen craft. After walking out of her workshop and taking off her gloves, she took some time away from her busy work schedule to share the details of her bar soap and liquid soap manufacturing processes with Stratton Magazine. Dorset Daughters’ soaps are both visually and aromatically appealing, but make no mistake – the craftwork that goes into Williams’ products is every bit as complex and nuanced as their refreshing and timeless scents.

Clean Chemistry, Clean Conscience

When making soap, Williams uses a combination of different natural oils and products as the base, including coconut oil, sunflower oil, and castor oil. The bar soap manufacturing process starts with the initial “pre-mixing” and “master batching” stages, in which the oils are combined together, stirred, and mixed in a 40-gallon tank. Although the ingredient ratios in all of Williams’ soaps (both bar and liquid) vary from product to product, the manufacturing processes for bar and liquid soaps remain almost entirely identical, regardless of the additional ingredients that are used. “I always use the same processes,” notes Williams. “What is fascinating, however, is that every oil and every fat that I use brings a specific quality that influences the overall feel of the soap. Coconut oil has wonderful cleansing properties. Still, you would never want to use a soap made completely out of coconut oil, because it would be very drying. I use sunflower oil to balance it out, which is great for conditioning. For my bar soaps, I also use shea butter, which is very nourishing. The castor oil brings a fine-bubble creaminess to the lather. You get the little bubbles from the castor oil, and the big bubbles from the coconut oil.”

After combining the oils, mixing them, and making one large “master batch,” Williams drains the oil from the master batch tank into five or six different smaller batches. Each smaller batch contains enough material to make 80 4.5-ounce bars of soap. Once the master batch has been separated into smaller batches, Williams heats the oils with an electric burner. The heat helps to clarify the oil and melt the fatty acids contained within, priming the mixture for the next step in the process. Williams then adds sodium hydroxide, an alkaline solution commonly known as lye, as well as natural scents and additives that enhance the soaps. “Some of the additives are placed in the soaps to improve their appearance,” Williams explains. “Others are added as exfoliants.”

When the aforementioned ingredients are all combined, the mixture thickens in consistency. “It becomes almost like a pudding,” says Williams. Williams adds that the thickening of the mixture is caused by a chemical reaction between the lye and the fatty acids. She elaborates: “The reaction breaks apart the fatty acids in the oils, which creates the soap molecules. The fatty acids in the oils are known as ‘triglycerides.’ When the chemical reaction breaks those compounds apart, you end up with three glycerin molecules and three soap molecules.” According to Williams, the unique molecular structure of the resulting compounds allows the soap to dissolve in both polar and non-polar solvents. In simpler terms, the soap is able to bond with both oil and water at the same time.

By doing so, it can effectively dissolve those compounds, remove them from surfaces, and then be easily washed away by water. Once the chemical reaction is finished, the soap is placed in a mold, where it sits, rests, and hardens for 24 hours. After the soap solidifies, it is removed from the mold and cut into 80 4.5-ounce pieces. The soap is then moved to a drying rack, where it “cures” for several weeks. When all of the excess moisture is removed by the curing process, the soap is then packaged and readied for sale.

The manufacturing process for Dorset Daughters’ liquid soaps begins with Williams mixing the foundational oils in a specialized piece of equipment known as “a water jacketed kettle.” Hot water runs between the kettle’s two exterior walls, heating the oils, while Williams stirs them every half hour for two days. “I try to mix the oils as often as possible,” says Williams. “I do let the mixture sit overnight, though, because sleep is important.” Williams says that the liquid soap is made with almost exactly the same ingredient mixture as the solid soap. The only two differences are that the liquid soap does not contain shea butter, and the lye that she uses to make the liquid soap has a different chemical composition. “The lye that I use for the solid soap is sodium hydroxide. I use potassium hydroxide for the liquid soap, which has a bigger molecular structure.” After the chemical reaction occurs between the oils and the potassium hydroxide, Williams fills the remaining space in the water jacketed kettle with distilled water or filtered Vermont spring water. When the water dilutes the alkalized oil paste into a thin, watery liquid, Williams tests it with an indicator solution to make sure that it is properly balanced and that there isn’t any excess lye. Afterwards, she adds a small amount of salt to thicken the solution.

When the process is finished, a ten-gallon batch is ready to be packaged. Each ten-gallon batch contains enough soap for approximately 100 bottles.

Williams then transfers the liquid soap solution to smaller buckets. From there, it is fed into a pneumatic bottling apparatus. After the bottles are filled, they are labeled for sale, and the process is complete.

Community Ties

Williams named her company “Dorset Daughters” in honor of her great-great grandmother, Carrie Pratt Gilbert, and her great-great aunts, Bertha Pratt and Ada Pratt. Williams is a proud member of The Gilbert family, who have long-established roots in Southern Vermont that date back at least seven generations. Although Williams was born in California and spent much of her life outside of the Green Mountain State, the time she spent in Vermont had a significant impact on her youth. According to Williams, her immediate family moved to Dorset in 1991 after her grandfather, who was living in the house at the time, passed away. She adds: “I attended high school here at BBA. Being here during high school was a formative part of my life, and really developed my love of the state and my feeling of it as home.”

After working for several decades in the fields of environmental consulting and corporate recruiting in California and Texas, Williams decided to return to her familial homestead in Dorset. The house that she currently shares with her husband and two children stands on a section of the original plot of land where her family once farmed sheep, which has been occupied by different members of the Gilbert family for six consecutive generations.

Williams arrived back in Vermont in 2013. In the years that followed, she was able to turn her fledgling soapmaking operation into a full-time occupation.

Nearly a decade later, Dorset Daughters has grown into a successful business with deep ties to the local community. Dorset Daughters products are now available for sale in several stores in the region, including The Kitchen Store at J.K. Adams and H.N. Williams in Dorset, Pearl’s Place & Pantry and New Morning Natural Foods in Manchester, Trillium in Brattleboro, and Crimson & Clover Farm in Northampton, Massachusetts, among others. Williams plans to increase the reach of her business and land her products in new stores through a targeted sales push campaign in the near future. Although she believes that the scaling potential for her business is nearly infinite, her insistence on high quality standards has led her to prioritize steady and sustainable growth over rapid expansion.

Over the years, Williams has diversified her product range to include additional items such as shampoo bars, conditioner bars, lotions, and dish cakes. She has also begun to manufacture products for several private label customers, as well, who entrust her with the creation of high-quality soaps and surfactants that are tailored to their specifications. Today, Williams uses the same water from Gilbert Spring that once fed the fields of her family’s farm to make her liquid soaps. By working closely with local farmers and gardeners, Williams carries on the time-honored Gilbert family tradition of locally-focused and ethical commerce through her business. She has also managed to integrate her passion for environmental conservation into her current line of work by sustainably sourcing many of the natural ingredients that she uses.

All of Dorset Daugters’ liquid soaps and solid soaps are composed entirely of vegan ingredients, with the singular exception of the Almond Blossom bar. Williams goes above and beyond to make use of locally-sourced ingredients in all of her products whenever possible. “It’s important to support our local economy and keep it vibrant,” says Williams. “It’s also important to support American manufacturers. I don’t think there’s any reason to be shipping things over long distances to take advantage of lower labor costs.”

In line with her firm belief in the importance of local collaborative commerce, Williams is currently in the process of developing a new solid soap with her friend, Mara Hearst, who handles her bookkeeping. “Mara is also the owner of Levy Lamb in West Pawlet,” adds Williams. “I just created a recipe for a new bar soap that will make use of Levy Farm beef tallow and sheep tallow, as well as lard from Greener Pastures in Pawlet. Mara is going to provide calendula flowers for the soap, as well.”

Williams also makes a special solid soap with her daughter, Maya Williams. The soap is manufactured using a sustainable recycling technique, and it serves the needs of local community members through a unique philanthropic initiative. “My daughter takes the waste trimmings from the solid soapmaking process, combines them, melts them down, and reforms them into new bars. You can see pieces of all of the different soaps in the reformed bars, which is really cool. Afterwards, we cut them up, package them, and donate them to the Community Food Cupboard in Manchester. We usually do a donation at least once a year. It’s our little way of giving back to the community that we love so much.”



Dorset Daughters currently has eight different kinds of bar soap available for sale, each of which is formulated with a signature blend of organic oils. The scent of their Vermont Sunshine bar has a citrusy top note with a woody finish, and their Lavender Farm bar contains lavender florets and rosemary essential oil, as well. The Summer Breeze bar has a bright lemongrass scent, and is packed with locally-sourced hempseed hulls that serve as a natural exfoliant. The Almond Blossom bar is made with locally-gathered honey from Trifolium Farms in Dorset and milk from grass-fed Jersey Cows raised in the nearby Mettowee Valley. Several of the bars have unique and earthy natural ingredients, including the Forest Glen bar, which features granulated pumice, and the Slate Valley bar, which is made with activated charcoal. Those who are partial to peppermint-scented soaps will adore the Mountain Mist bar, and Vermont History buffs will surely appreciate the cultural significance of the Danby Marble bar. It pays tribute to Southern Vermont’s enduring marble industry with marbled swirls of black and brown color, and has a heady scent with rose, ylang-ylang, and cedarwood. Dorset Daughters offers four varieties of liquid soap: Lavender Farm, Vermont Sunshine, Summer Breeze, and Almond Blossom. Dorset Daughters also makes lush and soothing lotions that are infused with those four scents, and bulk refills of their Vermont Sunshine liquid soap are available at the official Dorset Daughters soap refill station at The Kitchen Store at J.K. Adams.