These instructions explain how to make Cold Process soap from scratch.
Prepare your work area
Before beginning the soapmaking process, select a recipe and print a copy. Choose your work area. Typically an area of the kitchen is a good place to work, since there is access to the sink and stove. Any place that has good ventilation, a clean flat surface to work and an outlet for your stick blender is fine. Cover the counters in newspaper or drop cloths.
Gather your tools and supplies
- 2 Large mixing bowls (no aluminum)
- Small bowls for fragrance and color, if needed
- A Double boiler (stainless steel)
- Stick blender (plugged in)
- Measuring cups
- Two wooden or plastic spoons (one for lye and one for oils. Use these only for soapmaking)
- Two kitchen thermometers (one for the lye and one for the oils – must read to over 100 degrees)
- Rubber gloves and protective clothing
- Safety goggles
- Mold (lined or prepped if necessary)
- Old blanket or towel (optional)
- Bottle of vinegar
- Ingredients of the soap recipe
Prepare your Mold
Line or prep your mold as needed. Place mold near work area, ready to go.
Measure your Additives
Turn your scale on. Place a small bowl on the scale and press ‘tare’ – this sets the scale back to ‘0.’ Pour your fragrance into the bowl and stop when you have reached the correct weight. Set aside.
Prepare any colorants needed. If colorants are in liquid form, they are ready to use. If in powdered form, mix with a small amount of one of your oils or glycerin. Blend well, removing lumps and dry spots. Set aside.
If using any other additive, such as oatmeal, lavender buds, clays, etc. measure and prep these as needed. Everything should be ready to go when making soap, since time is critical.
Measure your Oils
Turn your scale on. Place bowl on the scale and press ‘tare’ – this sets the scale back to ‘0.’ Measure
all oils by weight, not volume. Melt and mix any solid fats in a double boiler. Pour the first oil into the bowl and stop when the weight is correct. It is VITAL that you measure precisely and accurately.
Press ‘tare’ and add the next oil to the bowl, measuring the weight. Continue these steps until all oils have been added to the bowl. Stir the oils and set aside. Use the thermometer to track the temperature of the oils. Oils have to be between 100-125° Fahrenheit, unless the recipe states otherwise.
Mixing your Lye
Put on your gloves and goggles. Using the scale as you did above, measure your lye into a bowl and set aside. It is VITAL that you measure precisely and accurately. Be sure to place the cap back on the lye container.
Measure your water. Used only distilled water as minerals in tap and spring water can adversely affect your soap. You can weigh the water or measure by volume. Be sure the bowl or cup is large enough to add water as well.
Slowly and carefully pour the lye into the water. ALWAYS ADD LYE TO WATER, not the other way round. The mixture will cloud and steam. Avoid breathing in fumes or splashing. Lye water must be between 100-125° Fahrenheit unless the recipe states otherwise. If it is taking too long to cool, make a water bath in the sink by partially filling the sink with water and ice. Place the container of lye mixture in the water bath and allow to cool to the correct temperature.
Add Lye Water to Oils
Once your oils and lye are between 100-125° Fahrenheit, carefully pour the lye water into the oils. ALWAYS ADD LYE TO OILS, not the other way round. Immediately run water in the empty lye bowl to rid it of active lye.
Give the mixture a quick stir with a spoon. Once the ingredients have combined, place your stick blender into the mixture FIRST and then turn it on. Blending will thicken the soap. To remove excess air bubbles, tap or tilt your stick blender. The soap mixture must reach trace. Trace is when you can see traces of the soap drizzled on top of the entire mixture or when a spoon is run through the mixture. It will look similar to pudding. Add your additives when trace is achieved. Blend well with the stick blender. Some fragrances known to cause problems in soap may have to be mixed in with a whisk.
Pour Soap into Mold
Once everything is in your mixing bowl and completely blended, it is time to pour the soap into the mold. Pour slowly and carefully, as raw soap can still cause lye burns. Tap the mold on a flat surface to eliminate air bubbles.
To prevent soda ash (a harmless white powdery looking substance that is sometimes a by-product of soapmaking) cover the soap with plastic wrap. Or you can spray the surface with 90% isopropyl alcohol. Do not use regular rubbing alcohol: it is not strong enough. Isopropyl alcohol can be purchase at drug stores and some grocery stores.
Optional: Wrap your mold in a blanket or old towel. This causes the soap to gel thoroughly. Gelling is part of the saponification process and makes the soap look shiny and gelatinous. Some recipes are better gelled; others are not. Gelling is entirely up to you.
Leave the soap alone for 24 hours. Clean your tools by hand with hot water and detergent. Throw away newspapers and wipe down work area. Once everything is cleaned, you may then take off your goggles and protective clothing.
Unmolding the Soap
After 24 hours, take a look at your soap. If it still looks gelatinous or feels warm to the touch, it is not ready to come out of the mold. Wait a few more hours or an extra day. If the soap feels cool and firm, you may remove it from the mold. Removing the soap will depend on the mold. Since this class assumes you will be using the small slab mold available in the Cold Process (CP) Starter Kit, just turn the mold over on top of freezer paper and gently press the bottom of the mold to release the soap. If it won’t come out, place the mold in the freezer for 1-2 hours. While the soap is cold, try to release the soap. It should come right out.
Cutting and Curing the Soap
Cut your soap into bars with a sharp knife or soap cutter. It will feel like cutting a block of fudge. Place your soap bars on a rack to cure and place them out of the way. They will have to cure on the rack for 4-6 weeks. Once the bars have hardened, they are ready for use. If you are unsure if soap is fully cured, you can test it using pH testing strips.