Cold Process Soap Making Instructions

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A 4-6 cup lye resistant container for mixing lye and water.  This container must be made of stainless steel, glass or heat resistant (212 degrees F) plastic.  It must not be made of aluminum or tin.

Another large heat resistant container or pot (stainless steel, enamel or plastic will work) for mixing the soap

A large saucepan for heating up the oils

Heavy duty rubber spatulas or wooden spoons for mixing

A good quality scale for measuring ingredients (it's nice to have one in ounces and another in grams if possible)

A soap mold - can be anything from a Rubbermaid(tm) type container to a wooden tray or even a heavy duty cardboard box.  Use your imagination and be on the look out for containers that will make nice molds.  It is adviseable to use something flexible so that the soap will come out easily with a little twist.

Wax paper or a plastic bag to line the molds with to prevent leaks and deterioration of the mold itself.  Replace cardboard molds when warped to avoid unshapely bars.

Two thermometers for checking the temperatures of the oils and the lye solution - the type used for candy making will work best (220 degrees F)

Goggles and rubber gloves

Safety First

Lye is a caustic substance. If you will be keeping your lye in the house or in other accessible areas, make sure to store it in a proper child proof container and educate all members of the family about the nature of lye.  Keep it away from areas where pets and young children have access. Children and pets should not be allowed in teh work area until all the equipment has been cleaned and put away.  Do not place pots/bowls near the edge of the counter.  Do not leave the area unattended.  Wear protective goggles and rubber gloves when working.  Wear long sleeves and close fitting clothing.  If you accidently get lye on your skin, flush the area with ordinary vinegar and wash well with soap and water. (Lye will feel slippery on skin.)  Never reuse lye containers for other purposes.  When mixing lye with water, always add the lye to the water and not the other way around.  Be careful not to inhale the dust when pouring the lye and work in a well ventilated area.

Although soap can be made anywhere, it is easiest if you have quick access to a stove and sink, making the kitchen the ideal work area.  Use the exhaust hood when mixing lye or mix outside.  Have adequate space to work on.

Put on protective eyewear and gloves.

Lay out all the equipment you need, line your mold with wax paper if necessary and measure out ingredients.  You can measure out the lye on a piece of wax paper square using a plastic spoon or scoop, just make sure to tare the scale with the paper first.  You must weight the lye accurately because an extra ounce is too much.  Lye amounts are calculated according to the saponification values of the oils in a recipe.  See the Saponification Value Chart.   When you are ready to experiment with your own recipes, you can use the Saponification Chart (comma delimited) that I provided for calculating how much lye and liquid would be needed for the quantities of oils you wish to use.

Pour the water into the appropriate container (remember, no aluminum!). Carefully pour the lye into the water and stir until dissolved.  Do not breathe in the fumes.  Leave the solution to cool to within 5 degrees of the required temperature of the recipe at which point you can start heating up the oils in a saucepan.  If you are using grapefruit seed extract, add it to the warm oils.

When the oils have reached the required temperature, check the lye temperature.  If it becomes too cool, place the container in another container filled with hot water.  Do not attempt to heat the lye in a microwave or on the stove.  The oils will heat quickly so remove the saucepan from the heat source when the temperature is within 5-10 degrees of the required temperature.

When the correct temperatures have been reached, pour the oils into the container that you will use to make the soap.  While stirring, pour the lye carefully into the oils.  Stir continuously until the soap traces. Tracing is described as the point at which the soap will eave a mark when soap from the spatula is drizzled over the surface of the soap in the container.

At this point, stir in any nutrient oils, color pigments and essential or fragrance oils but work quickly.  Some fragrance oils will cause the soap to suddenly solidify.  Grapefruit seed extract will cause a quicker trace than usual.

Pour soap into mold and cover with a piece of wood or wrap with an old blanket or towel.  Leave the soap undisturbed for at least 24 hours until it cools.  The soap should be firm with no pools of oil on top.  If it's not firm, wait another day or so and check again.

Remove the soap from the mold and slice into bars.  If you have trouble getting the soap out of the mold, try placing the mold in the freezer overnight and it should then pop out easily.  The soap needs to cure for the given amount of time in the recipe.

You can check to see if it's cured by washing your hands with it.  If it leaves a slimy feeling, leave it to cure for another week.

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