The melt and pour method of making soap is the safest to partake in, as the basic principle is melting a pre-made soap base and pouring it into a mold. Soap bases melt and pour are ready to use within hours after being made, and they allow for countless variations of artistic effects that can be achieved with additives. This form of soap-making can be likened to baking a cake with a dried cake mix to which you need add only a few more ingredients to enhance its quality. Working with melt and pour soap means the “saponification process” – the process that converts lye or fats into soap – has already been completed and has yielded a base that is ready to use and personalize.
In order for melt and pour soap base to be produced, the saponification process needs to be complete. This entails mixing an oil or fat, which is known as the “acid” with lye, which is the “base.” The end result is the soap, which is considered to be the “salt.” When the mixture cools, it is poured into a suitable mold to cool and set. Once it has cooled it can be melted again to create several fun and unique soaps.
Melt and pour soap contains a high percentage of glycerin, which means it has a highly moisturizing quality that makes it gentler on skin than store-bought soaps. Glycerin is a component of fat or oil and is a natural byproduct of the saponification process. Glycerin is a humectant, which means it attracts moisture and this is what lends soap its moisturizing property. When exposed to humidity, melt and pour soap tends to “sweat,” because the glycerin attracts moisture from the air, so they must be kept as dry as possible on well-draining surfaces.
The difference between Cold Process soap making and Melt and Pour soap making is that in the former process, soap is made from scratch using lye as one of the main components. Lye is not as easily obtained as melt and pour soap bases, because it is only supplied by chemical companies or hardware companies. This process also requires more safety measures such as goggles and gloves due to the caustic nature of the lye in which oils are mixed. On the other hand, melt and pour soap bases are pre-made and sold in blocks that are ready to be melted down to make customized soap. The process is safe enough for children to partake in, because there is no need for the corrosive solution to be used. Cold Process soap needs to sit for six weeks in order for it to harden and for any excess liquids to evaporate before it can be used. Melt and pour soap dries and hardens faster than cold process soap making, which means it is ready to used much sooner.
BELOW ARE SOME COMMON ADDITIVES:
LabColor Size |
Amount of Diluted LabColor (for CP) |
Amount of Soap - Light Tint |
Amount of Soap - Deep Tint |
small |
4 ounces |
59 pounds |
15 pounds |
large |
8 ounces |
118 pounds |
30 pounds |
jumbo |
50 ounces |
737 pounds |
184 pounds |
Moisturizers such as vegetable butters, vegetable oils, and clays can be added as the melt and pour soap base is heated. It might seem counterintuitive to use clay as a moisturizing ingredient, as it is known to have properties that draw out the moisture from the skin, but in its damp phase, it exudes beneficial minerals. The rate of usage for moisturizers is approximately 1 – 2 tbsp per pound (0.45 kg) of soap base.
Adding a moisturizer like Mango Butter will allow your soap to help combat skin irritations such as dryness, fine lines, wrinkles, sunburn, insect bites, rashes and stretch marks. Conditioning butters like Shea and Cocoa provide a creamy lather as well as hardness to the soap. Cocoa Butter helps skin retain moisture and protects it against harsh environmental pollutants by creating a barrier, and it provides soap with the added benefit of its mild, pleasant smell.
Clays such as Rhassoul will not only clean and firm but also condition and nourish the skin. To add clay to a soap base without causing the clay to clump when it comes in contact with the soap, it must first be made into a paste with distilled water. 0.33 tbsp (1 tsp) of clay can be distilled in 1 tbsp of distilled water. Clays tend to add earthy colors to soaps.
Soaps can be scented with fragrance oils, which are synthetic or with essential oils, which are natural. They are added to melt and pour soap base before it is removed from the stove to be poured into the mold, as these scents will not melt properly in soap that has already cooled. Adding scents at this time helps make them last, although the strength of scents varies from oil to oil. Kaolin clay is a common additive for scented soaps, as it helps the soap retain its aroma by giving the fragrance something to “stick” to. What also helps soap retain its scent is storing the final product in a cool, dry place out of direct sunlight.
Fragrance oils may contain ingredients that have natural colors – vanillin is one example – and the soap color can be affected by these natural colors. In the case of vanillin, it turns soap brown over time. The color of some essential oils might also affect the color of the soap. NDA supplies Vanilla Stable Melt & Pour Glycerin Soap Base, which is formulated to prevent browning over time when fragrances containing Vanillin are used.
For melt & pour soap, the recommended amount of fragrance oils is 15 ml per pound (0.5 oz per 0.45kg) of soap, and the recommended amount of essential oils is 7.4 ml per pound (0.25 oz per 0.45kg) of soap.
It is highly recommended that soap makers thoroughly read and understand the vendor’s safety instructions for usage before adding the appropriate ratio of fragrance/essential oils to the soap-making process. It is important to consider how skin will react to the particular essential oils used as well as how they might dissipate in reaction to heat.
Exfoliants are ingredients with textures and properties that lend them the ability to polish dry, dull skin. They work to remove the dead cells on the top layer of skin. To prevent a layer of exfoliating botanicals from forming in the soap, it is a good idea to avoid using too much of the exfoliant and to ensure continuous stirring of the soap batter after the exfoliants have been added. In general, the rate of exfoliant usage is 1 – 2 tablespoons per pound (0.45 kg) of soap. If a coarse, abrasive soap is desired then the amount of exfoliant needs to be higher than this recommended base amount.
Extracts introduce the beneficial properties of their original plants into the soap. They can be added to the melted soap at a rate of 1-2 tbsp per each pound (0.45 kg) of soap and stirred in with a spoon just before the mixture is poured into the mold. The following are some popular choices for extracts that are incorporated into the melt and pour soap making process:
A clean stretch of countertop or table that would be wide enough to prepare a cake
Melt and pour soap base
A microwave or stove and double boiler to melt the soap base
A sharp knife or dough cutter for cutting enough of the base to fit the desired mold after it is melted
A large heat resistant measuring cup that measures 1 liter (4 cups) or a microwave safe bowl in which to place the chopped base for melting
A heat-resistant spoon for mixing the base
Any kind of heat-resistant mold from which soap can easily be released (avoid using hard plastic or metal, which can react with and discolor soap ingredients)
Any additive can be included in a melt and pour soap mixture, including fragrances, colorants, skin care nutrients such as herbs, butters, exfoliants, and sparkles and more.
A small spray bottle of alcohol
See our full oap making supplies section as well!
Sterilize the soap-making area, which should be large enough to prepare a cake mixture.
Cut the desired amount of soap base into small squares. Every pound (0.45 kg) of soap base will yield 4-6 bars.
Place the squares into A) a microwave safe bowl and heat them at short intervals of 15-20 seconds, stirring gently with each heating, B) a double boiler - a saucepan that is half full of water, which is heated until it boils. A second pan containing the chopped soap base is placed inside this saucepan. The heat from the bottom pan is transferred to the second pan and melts the soap base.
With a heat-resistant spatula, stir the melted soap base slowly between each heating to avoid creating bubbles. If bubbles do arise, they can be dispersed with a spritz of alcohol from the spray bottle. Stirring slowly is also conducive to maintaining the right temperature for the soap, as soap bases lose water when heated at too high a temperature.
Remove the soap from the heat source before it is completely melted and continue to stir it until the heat of the mixture is dispersed consistently throughout. At this point, essential oils, fragrance oils, colorants and other additives can be added while the mixture is stirred gently.
Pour the melted soap base into the desired mold, ensuring that it is level. Any bubbles that form can be dispelled with a spray of alcohol. Fragrance oils might cause the soap to “weep,” which means the soap will feel wet and oily, so it is a good idea to do a batch test when using them.
Allow the soap to sit and completely cool inside the mold. This wait time can be a couple of hours long or it can even cool overnight.
Carefully release the soap from the molds onto a clean, flat surface with a tea towel or a paper towel to prevent denting any stubborn soaps stuck inside their molds. If this happens, a soap can be further frozen for 15-30 minutes to for easier removal. After being taken out of the freezer, hold the mold under hot water to melt the coating. The soap should then be easily peeled out.
Any rough edges can be smoothed down with a paring knife and a clean cloth moistened with alcohol.
Allow the soaps to air dry before packaging them, as any moisture trapped inside the packaging can make the soap slimy. Cellophane bags or shrink wrap are ideal for wrapping soap. It is best to wrap soap immediately after it has finished cooling, as this will prevent the soap from shrinking because of evaporated water content.
To ensure that soaps will be easily released from their molds, a coating can be applied to the molds.
Gently heat the following ingredients:
1 tbsp petroleum jelly
1 tbsp mineral oil (baby oil)
This mixture can be kept in a jar and can be spread onto molds with a small pastry brush to lightly coat the molds. Silicone brushes found in the cooking section of your local dollar store are great for this.
Before incorporating any additive into a soap recipe, it is important to understand the amount that can be safely used. Too much of an additive might lead to issues such as the breakdown of chemical bonds or it might necessitate the use of preservatives.
Only heat-safe equipment should be used to make soap as the melting temperatures generally reach above 48 áµ’C (120 áµ’F). When skin is exposed to hot soap, it is painful.
Fresh ingredients such as fruits, vegetables, or milk are best avoided in a melt and pour soap recipe, as they will always spoil eventually.