A Twist on Cold Process Soapmaking: The Room Temperature Method
Reading Time: 4 minutes
It’s no surprise that many consumers are turning to homemade soap for their body wash, hand soap, and even shampoo and conditioner needs. Today’s retail market is heavily saturated with bars that are simply detergent; chemical compounds, water, and synthetic fragrances intended to cut through grease, dirt, and oils without leaving any residues behind. This approach to creating body bars may provide a long-lasting scent but it also can drain many skin types of hydration and leave skin irritated and prone to rashing with its harsh cleaning ingredients.
True soap is actually the blended combination of saponified oils, colorants, and fragrances. While some soapers may use scientifically derived colorants like mica powder and faux scents, it’s the oil solution in the soap that acts as a humectant — hydrating the skin in addition to removing debris.
There are three common approaches to soapmaking; Cold Process, Hot Process, and Melt and Pour. Most soapers can easily distinguish which method was used to create a bar based solely on its appearance. Cold Process soap tends to be lighter in color, almost takes on a translucence, and boasts a smooth, clean finish. Hot Process soap bars are a bit more textured in looks and typically described as “rustic.” The bar tends to look more opaque and a little flatter in color. Finally, Melt and Pour soap products are known for their glycerin-based, crystal-clear bars, often playfully decorated with color additives, florals, luffa bits, or even small toys nestled within the soap bars.
But did you know that there’s actually a fourth method for creating soap which is an extension of the Cold Process? This lesser-known approach to soapmaking offers the creamy and opaque look of a rustic Hot Process bar with the smooth and silky finish which results from the Cold Process. This method is called Extra Cold Process soapmaking or sometimes referred to as The Room Temperature Method.
In Cold Process soapmaking, the lye and oil solutions are combined at a temperature range of 120º-130ºF. But Extra Cold Process soap is created by using no heat source at all. Imagine a soapmaking process that still requires great attention to the weight of ingredients in grams or ounces, but that doesn’t require temperature readings of any of its ingredients. The lye and water solution will naturally heat up as a result of its chemical reaction, but this heat is simply used as a melting agent for cold and congealed coconut oil, shea butter, or other solids that need to be melted before adding to the soap recipe.
The benefits of this method of soapmaking go beyond just saving time and effort in terms of heating up oil solutions and saving you the hassle of conducting temperature readings. The lower temperatures prevent the soap from reaching what’s known as the “gel phase.” This gel phase avoidance extends the life and strength of any fragrances used within the bar. The bar also hardens more quickly and can be removed from the molds much sooner (though Extra Cold Process bars still require four to six weeks to cure before use). Some soapers will say that the color of their bars is more vibrant as well.
Essential oils and other natural fragrances can easily become dampened and weakened when heated to high temperatures around 180ºF during the gel phase — that natural reaction during the soap saponification process. But when Room Temperature soap batches begin to harden, the gel phase isn’t reached and the temperature retains a lower temperature range while hardening. Delicate fragrances that can easily become cooked and lost in warmer soap processes are more sustainable when used in the Room Temperature Method. Soap recipes containing honey, milk, or fruit additives often call for executing the Extra Cold Process approach to prevent cooking, scorching and rancid-scented results.
As for the actual lather and efficacy of the bar? Extra Cold Process soap or Room Temperature Process bars still offer a luxurious lather and clean the skin of oil and residue just as effectively.
How to Adapt a Cold Process Soap Recipe to the Basic Room Temperature Soap Method
This basic Extra Cold Process soapmaking adaptation assumes that you are familiar with the safety requirements and precautions surrounding handling sodium hydroxide. An understanding of oils, lye, supplies, and cold process soapmaking, in general, is required.
Prepare your soap mold, retrieve your desired Cold Process Soapmaking Recipe, and measure out all oils, water, sodium hydroxide, and any additives such as fragrances or clays. Combine all weighed and measured hard oils such as coconut oil, butters, etc. into a soaping container. Weigh liquid oils and combine them in a second soapmaking container (such as olive or avocado oils). Create your lye solution by adding the pre-measured sodium hydroxide to the water and stir to dissolve. Once the lye solution is clear of crystals, pour the solution over the hard oils in the first soaping container. Gently stir and dissolve the hard oils and butters until all is melted. This may take some time. Add the liquid oils and stir to fully combine. Next, use a stick blender to bring your soap solution to a thin trace. Add your fragrances and any additional ingredients and gently stir until evenly distributed. Pour into your prepared soap molds, cover with a towel to keep the heat in, and allow to set. As with any other soap recipe, soap should only be removed and cut into bars when it is solid and firm enough to handle without creating indentations. Cure for four to six weeks before use.
Do you make homemade soap? Which soapmaking process do you prefer?
Angela Ferraro-Fanning and her family are first-generation farmers on a historic New Jersey homestead established in 1775. Their homestead currently consists of vegetables, orchard fruit, sugar maples, dogs, barn cats, geese, ducks, Clydesdales, and honeybees.