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Q: How do I make soap using the hot processed method?

Hot Process Soap making
Keeping cold-process soap properly insulated is important when pouring into individual 3 and 4 ounce cavities. Heat loss can be a problem due to a large surface area relative to a small volume of soap. This heat loss can retard saponification. One solution to this potential problem is an elevated pour temperature in the range of 115-125 degrees F. Another method involves pre-cooking the soap so that it's thoroughly saponified before being poured into the molds. This is hot-process soap making.

What are the advantages of hot-processing? One, the soap doesn't need to be insulated since it's neutral when spooned into the molds. It just needs to cool and harden, which takes 1-2 hours. Two, neutral soap is much gentler on dyes and fragrances - you'll find both stay "truer".

I introduced a simple hot-process technique in my book Making Transparent Soap. This method can be tailored to any formulation. The steps are as follows:1. Use two pots for soap making: one, your soap pot, and two, a kettle large enough to comfortably contain your soap pot. An enamel five-gallon canning pot is ideal for most situations. This second kettle will become the bottom of a double boiler. Fill it with 3-5 inches of water.2. Stir your soap until traced. Meanwhile, bring the water in the large kettle to a slow boil.3. After tracing, place the soap pot inside the kettle. Keep the water at a gentle boil; cover if possible to retain heat.4. Cook your soap for 1 3/4 hours. During this time it should become a soft translucent salve. Translucency is a sign that the soap is neutralizing.

Stir briefly 2 or 3 times during cooking to ensure even heat distribution throughout the soap mass.5. After 1 3/4 hours the soap will be neutral. Dye, fragrance and spoon into molds. If the soap seems too thick to work with, thin with a few ounces of alcohol. Start with 2-3 ounces; gradually add more if needed. Pure ethanol (Everclear), 90%-99% isopropyl or vodka all work well. When dividing the soap up for different fragrances and colors, keep the unused portion hot, or it begins hardening as it cools. Hardened soap can be "remelted" over a double boiler. And finally, any air pockets in the molded soap? These can be removed by gently tapping the mold on the counter top. Another method for removing air bubbles is to cover the top of the soap-filled cavities with a sheet of plastic film. With the palm of your hand, press the soap gently but firmly into the cavity.

All mold designs copyright 1998, 1999, 2000, 2001 by Catherine Failor
All rights reserved

Q: How do I care for and use Milky Way Molds?




Use warm tape water and soap (if the molds have been used for soapmaking, simply soak in warm water for a half hour or so). Hot water, including dishwasher water, may warp the plastic.


The molds can tolerate wax and transparent soap temperatures of 135-145 degrees F. If you’re concerned about warping, set the molds in a shallow cold-water bath for hot-temperature pours.


Please don’t manhandle the molds when releasing contents! If you have any difficulties with soap or chocolate, place the molds in your freezer. For chocolate, a few minutes of freezer time will allow for easy unmolding. For soap, ½- 1 hour should be sufficient.


Because opaque cold-process soap undergoes a chemical reaction in the molds, there are a few extra considerations to keep in mind. (Note: these considerations don’t apply to transparent soap since it’s neutral when poured. Transparents also lack "stickiness," so there shouldn’t be any problem unmolding them.)

Soap needs a certain amount of heat to saponify properly. Most cold-process soap books call for pour temperatures of 80-100 degrees F. These temperatures are fine if you’re pouring several pounds into one large mold, but when soap is poured into individual 3 or 4 ounce molds, heat is more easily lost regardless of how much insulation you use. If you’ve measured your ingredients correctly but your finished soap is soft and/or grainy, raise the soap’s temperature to between 115-125 degrees F. next time you pour. 
When filling many cavities, realistically consider just how much working time you have before your soap begins to thicken beyond the "easy-pour" state. Dividing soap up into smaller portions for different colors and fragrances will slow you down; some artificial fragrances will speed the thickening. If this is the case, think about making smaller batches. If your soap does thicken before all the cavities are filled, spoon the soap in and tap the molds lightly on the counter top. The clear plastic will allow you to see if any air bubbles remain on the mold’s detail surface. 
Superfatted soap and/or soap high in soft oils such as canola, avacado, safflower, etc. are a bit sticky, and therefore may unmold with more difficulty than firmer soaps high in palm oil or tallow. These softer soaps will unmold if placed in the freezer for ½-1 hour. For a firm, easy-release soap with a good lather try: 

22 ounces palm oil or tallow
3 ounces coconut oil
2 ounces olive, canola or any other soft oil
4 ounces sodium hydroxide
8 ½ ounces water

Heat oils to 115-125 degrees F. then add 115-125 degree lye solution. Stir until traced. If temperature has dropped much below 115-125 prior to pouring, reheat on stove top. Makes 2 ½ pounds, or enough soap to fill approximately 9-10 cavities. PS- Mold designs also show up clearer and "crisper" in hard soap than in soft soap.

More on unmolding soap: 
If the soap is allowed to remain in the molds for 12-24 hours after cooling down, it releases much more easily than unmolding it immediately upon cooling. (During this extra time the soap is both shrinking and crystallizing.) One final option: If you’d like to experiment with a fairly effective mold release, melt one part paraffin wax then stir into 3 parts mineral or baby 0il. Best used when hot and liquid, but if applied to the molds when cold (as a soft paste) use a stiff brush to insure thin and even application, otherwise inconsistencies can mar the smoothness of the finished soap. Plain mineral or baby oil can also be used to lightly coat the molds (vegetable oils or PAM may possibly saponify if used as a mold release).

All mold designs copyright 1998-2013 by Catherine Failor
All rights reserved.

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