Hot-Process Equipment

In addition to the equipment needed for cold-process soapmaking, the hot-process technique requires either a slow cooker or a double boiler.

Slow Cooker

The recipes in this book call for a slow cooker. They are easy to use, self-contained, and convenient. You can purchase slow cookers at mass market, outlet, overstock, and thrift stores. The recipes in the book call for a 3.5-quart slow cooker. If you want to increase the size of your recipe, get a bigger slow cooker. Just make sure you have enough headroom to accommodate the puffing up that will often happen. An overflowing mass of caustic soap is a surprise you don't want.

Slow cooker at a half hour

There are mini — slow cookers and great big eight-quart slow cookers. Just be absolutely sure your slow cooker has enough room for your soap. Calculate the volume of your batch — oils plus water plus lye — and fill the crock with that much water. There should be at least two inches of free space left from the top of the slow cooker to the surface.

Slow cooker at “applesauce” stage

Double Boiler

Instead of a slow cooker, you can cook your hot-process soap in a double boiler made from two large pots, one placed inside the other. Depending on the size of your recipe, you can use something as large as a canning kettle with a twelve-quart stock pot inside, down to one small saucepan placed inside another.

Learning to make opaque hot-process soap is a gateway to making transparent, liquid, and cream soaps. These methods can be seen as an extension of hot processing and are better attempted after gaining some facility with hot processing solid, opaque soap.

Note that the type of commercial “sit on top” double boiler you buy in stores is not the ideal pan for small batches of hot-process cooking. It's better to have the soap pot partially submerged in the boiling water of the bigger pan.

Kitchen supply stores usually carry a trivet-like object for “making” a double boiler. You place it in the bottom of the larger pot and sit the smaller pot on top of it.

Getting Started

You can use just about any cold-process recipe to make an opaque hot-process batch. (This is not true, though, for liquid and transparent hot-process recipes, which require different ingredients.) It is a good idea to make the recipe as a cold-process batch first to know what to expect.

Although cold process takes weeks to neutralize, waiting can be less stressful for beginners than cooking the soap to neutrality. Know that, like any new recipe and technique, hot-process soapmaking will become routine for you. It is a happy soapmaker who has many techniques and processes at her disposal.

This basic recipe is the same as the basic cold-process recipe. However, the convenience that you find with a one-pound batch in cold-process soapmaking isn't that convenient with hot process. It's easier to get the cook going with a bigger batch. Additionally, too large a batch can be quite unwieldy. The recipes here are a compromise — not too small, not too large.

Basic Hot-Process Soap

Yields 3 pounds

1 pound, 3 ounces olive oil

3 ounces palm kernel oil

10 ounces coconut oil

12 ounces water

4.5 ounces lye

2 tablespoons castor oil

Your choice of scent materials

Your choice of color

Your choice of other additives

This recipe makes a basic kitchen soap. A good kitchen soap should do a number of things. First, it should clean your hands gently. Second, it should be able to remove grease and food residue. Third, it should have some deodorizing properties. Additionally, it can be colored and scented to go with your kitchen.

  • Combine and melt the olive oil, palm kernel oil, and coconut oil in the slow cooker.

  • Place the water in a heatproof container. Slowly add the lye to prepare the lye solution. Heat the oils and cool the lye solution to 110°F. Pour the lye solution into the oils, slowly and carefully. Stir to trace. Add the castor oil.

  • Cook in slow cooker, 3 hours on low setting. Check for consistency every 30 minutes. Check pH. Add scent materials, color, and other additives when neutral.

  • Fill molds, let cool, and set. Unmold, cut into bars, and store as usual.

Coffee Kitchen Soap

Yields 3 pounds

2-pound batch recipe of your choice, substituting strong brewed coffee for the water

2 tablespoons finely ground coffee

It is common soapmaking lore that ground coffee has a deodorizing effect on the skin. Coffee is said to be able to remove the odors of garlic and onions from your hands. You'll have to see for yourself. But there is definitely a useful scrubbing action from the ground coffee.

  • Make a 2-pound batch, substituting strong brewed coffee for the water. Stir to a good medium trace.

  • Cook as usual. Check pH. Continue cooking if it's still caustic, until the soap is neutral.

  • Stir the finely ground coffee into the neutral soap.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Super-Clean Kitchen Soap

Yields 3 pounds

2-pound batch recipe of your choice

2 tablespoons yellow cornmeal

½ teaspoon orange essential oil

½ teaspoon eucalyptus essential oil

½ teaspoon lavender essential oil

The cleaning power of this soap starts with the blend of essential oils. Orange, eucalyptus, and lavender essential oils are great grease cutters. These essential oils are also known for their reported antibacterial properties. Cornmeal adds brisk abrasive action.

  • Make up the batch as usual and stir to a good medium trace.

  • Cook as usual until the soap is neutral. Check pH. Continue cooking if it's still caustic, and check again.

  • Stir the yellow cornmeal into the neutral soap. Add the orange, eucalyptus, and lavender essential oils. Stir well.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Lemon/Baking Soda Kitchen Soap

Yields 3 pounds

2-pound batch recipe of your choice

2 tablespoons lemon zest

3 tablespoons baking soda

Lemons have long been prized for their ability to reduce kitchen odors, as has baking soda. Baking soda is also a gentle abrasive. Lemon zest helps cut grease and adds a fresh lemon scent.

  • Make up the batch as usual and stir to a good medium trace.

  • Cook as usual until the soap is neutral. Check pH. Continue cooking if it's still caustic, and check again.

  • Stir the lemon zest and baking soda into the neutral soap.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Peppermint Bath Soap

Yields 3 pounds

2-pound batch recipe of your choice, substituting strong mint tea — made from fresh peppermint, mint tea bags, or loose tea, strained well and cooled — for the water

1 tablespoon mint, dried and ground (you can use the contents of a mint tea bag)

½ teaspoon peppermint essential oil

Every tub should have at least one good bath soap. Single essential oils can make for an easy choice in the morning. Choose peppermint for a brisk awakening.

  • Make up the batch as usual and stir to a good medium trace.

  • Cook as usual until the soap is neutral. Check pH. Continue cooking if it's still caustic.

  • Stir the mint into the neutral soap. Just before you pack the soap into the molds, add the peppermint essential oil. (Wait as long as possible to stir in the essential oil. It is extremely volatile — readily vaporized — and your house will smell like an explosion in a toothpaste factory.)

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Lavender Bath Soap

Yields 3 pounds

2-pound batch recipe of your choice, substituting a lavender infusion for the water

1 tablespoon dried lavender flowers

1 teaspoon lavender essential oil

To make the lavender infusion called for in this recipe, use 2 tablespoons of lavender for each cup of water in the recipe. Heat the water and pour it over the lavender. Let cool, then strain out the lavender. Remeasure. Add more water to compensate for any volume that may have been lost due to evaporation.

  • Make up the batch as usual and stir to a good medium trace.

  • Cook as usual until the soap is neutral. Check pH. Continue cooking if it's still caustic.

  • Stir the lavender flowers into the neutral soap. Add the lavender essential oil and stir completely.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Eucalyptus Bath Soap

Yields 3 pounds

2-pound batch recipe of your choice, substituting a yarrow infusion for the water

1 tablespoon yarrow (remove stems and stiff parts)

1 teaspoon eucalyptus essential oil

Eucalyptus soap is a great choice for when you're feeling under the weather. To make the yarrow infusion called for in this recipe, use 2 tablespoons of yarrow for each cup of water in the recipe. Heat the water and pour it over the yarrow. Let cool, then strain out the yarrow. Remeasure. Add more water to compensate for any volume that may have been lost due to evaporation.

  • Make up the batch as usual and stir to a good medium trace.

  • Cook as usual until the soap is neutral. Check pH. Continue cooking if it's still caustic.

  • Stir the yarrow into the neutral soap. Add the eucalyptus essential oil and stir completely.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Rosemary Bath Soap

Yields 3 pounds

2-pound batch recipe of your choice, substituting a rosemary infusion for the water

1 tablespoon finely chopped rosemary

1 teaspoon rosemary essential oil

Rosemary is great for mental focus. To make the rosemary infusion called for in this recipe, use 2 tablespoons of rosemary for each cup of water in the recipe. Heat the water and pour it over the rosemary. Let cool, then strain out the rosemary. Remeasure. Add more water to compensate for any volume that may have been lost due to evaporation.

  • Make up the batch as usual and stir to a good medium trace.

  • Cook as usual until the soap is neutral. Check pH. Continue cooking if it's still caustic.

  • Stir the rosemary leaves into the neutral soap. Add the rosemary essential oil and stir completely.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

I don't have a slow cooker. Can I still use these recipes?

Though the recipes and instructions are given for a slow cooker, you can easily adapt them to a double boiler. Be sure to read each recipe and directions each time, since there are variations in the techniques depending on the size of the batch. Don't forget your goggles and gloves, and add some oven mitts to your safety gear!

Soap for Dry Skin

5 ounces olive oil

5 ounces coconut oil

3 ounces shea butter

3 ounces avocado oil

6 ounces water

1 tablespoon dried chamomile

2.25 ounces lye

½ ounce castor oil

10 drops German chamomile essential oil

5 drops rose otto essential oil

2 drops jasmine essential oil

5 drops palmarosa essential oil

  • Combine and melt the olive oil, coconut oil, shea butter, and avocado oil in the slow cooker.

  • Make a chamomile infusion by heating the water and pouring it over the chamomile. Let cool, then strain out the chamomile. Remeasure. Add more water to make 6 ounces, to compensate for any volume that may have been lost due to evaporation.

  • Place the chamomile infusion in a heatproof container. Slowly add the lye to prepare the lye solution. Heat the oils and cool the lye solution to 110°F. Pour the lye solution into the oils, slowly and carefully. Stir to trace. Add the castoroil.

  • Cook in slow cooker, 3 hours on low setting. Check for consistency every 30 minutes. Check pH.

  • When the soap is neutral, add the essential oils and stir thoroughly.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Soap for Skin That's Not Too Oily Nor Too Dry

8 ounces olive oil

4 ounces coconut oil

4 ounces macadamia nut oil

6 ounces water

1 tablespoon dried lavender

2.25 ounces lye

½ ounce castor oil

5 drops German chamomile essential oil

2 drops rose otto essential oil

⅛ teaspoon lavender essential oil

  • Combine and melt the olive oil, coconut oil, and macadamia nut oil in the slow cooker.

  • Make a lavender infusion by heating the water and pouring it over the lavender. Let cool, then strain out the lavender. Remeasure. Add more water to make 6 ounces, to compensate for any volume that may have been lost due to evaporation.

  • Place the lavender infusion in a heatproof container. Slowly add the lye to prepare the lye solution. Heat the oils and cool the lye solution to 110°F. Pour the lye solution into the oils, slowly and carefully. Stir to trace. Add the castor oil.

  • Cook in slow cooker, 3 hours on low setting. Check for consistency every 30 minutes. Check pH.

  • When the soap is neutral, add the essential oils and stir thoroughly.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Soap for Oily Skin

6 ounces olive oil

4 ounces coconut oil

6 ounces grapeseed oil

6 ounces strong black tea

2.23 ounces lye

½ ounce castor oil

¼ teaspoon lavender essential oil

5 drops cedarwood essential oil

5 drops lemongrass essential oil

5 drops rosemary essential oil

  • Combine and melt the olive oil, coconut oil, and grapeseed oil in the slow cooker.

  • Place the tea in a heatproof container. Slowly add the lye to prepare the lye solution. Heat the oils and cool the lye solution to 110°F. Pour the lye solution into the oils, slowly and carefully. Stir to trace. Add the castor oil.

  • Cook in slow cooker, 3 hours on low setting. Check for consistency every 30 minutes. Check pH.

  • When the soap is neutral, add the essential oils and stir thoroughly.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Soap for Acne-Prone Skin

11 ounces olive oil

5 ounces coconut oil

6 ounces water

1 tablespoon hibiscus tea blend

2.25 ounces lye

1 tablespoon bentonite or kaolin clay

½ ounce castor oil

6 drops tea tree essential oil

6 drops lavender essential oil

6 drops rosemary essential oil

  • Combine and melt the olive oil and coconut oil in the slow cooker.

  • Make a hibiscus tea by heating the water and pouring it over the hibiscus tea blend. Let cool, then strain out the hibiscus. Remeasure. Add more water to make 6 ounces, to compensate for any volume that may have been lost due to evaporation.

  • Place the tea in a heatproof container. Slowly add the lye and the clay to prepare the lye solution. Heat the oils and cool the lye solution to 110°F. Pour the lye solution into the oils, slowly and carefully. Stir to trace. Add the castor oil.

  • Cook in slow cooker, 3 hours on low setting. Check for consistency every 30 minutes. Check pH.

  • When the soap is neutral, add the essential oils and stir thoroughly.

  • Pack into molds, let cool, and set. Unmold, cut into bars, and store as usual.

Perfect Facial Soap

Contrary to common understanding, soap and water are good for almost any face. It just has to be the right soap. Properly formulated handmade soap makes a great facial soap. Whether your skin is dry, average, oily, or prone to breakouts, there is a good chance handmade facial soap will work for you.

The following recipes make small batches, as you'll be using more costly ingredients. You can, of course, make these recipes using the cold-process technique, but with hot process, you can use less of the costly essential oils. Cool the soap as much as you can before stirring in the essential oils. This way you'll have less evaporation of the precious oils.

Unmolding

Getting hot-process soaps out of their molds can be a challenge. You'll have to use trial and error. Some batches are just stickier than others. Some may release with no trouble at all, and others may take extended time in the molds before they'll release.

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