class category: Castile Soap Making

In this class, you will get a complete list of the ingredients, tools and equipment to make Hot Process Liquid Castile Soap.

Customizing Your Liquid Castile Soap

Customizing Your Liquid Castile Soap

One of the biggest benefits of homemade liquid Castile soap is the ability to customize it to your liking. Whether you want a refreshing scent, a soothing moisturizer, a vibrant color, or a thicker texture, this lesson will show you how to personalize your soap with natural additives.

 

1. Adding Essential Oils for Scent & Skin Benefits

Essential oils not only provide pleasant fragrances but also offer aromatherapy benefits and skin-enhancing properties. Here are some popular choices:

Popular Essential Oil Options:

🌿 Lavender – Calming, great for sensitive skin, promotes relaxation.
🌿 Peppermint – Energizing, cooling effect, great for morning showers.
🌿 Tea Tree – Antibacterial, antifungal, ideal for acne-prone or oily skin.
🍊 Citrus Blends (Lemon, Orange, Grapefruit, Lime) – Uplifting, cleansing, and refreshing.

💡 How to Add Essential Oils:

  • Once the soap has cooled to room temperature, add 5-10 drops per 8 oz of soap.
  • Stir well to distribute evenly.

 

2. Natural Coloring Options

While Castile soap is naturally a light golden color, you can use natural ingredients to create unique colors without synthetic dyes.

Safe & Natural Color Additives:

🖤 Activated Charcoal – Creates a deep black or gray soap, great for detoxifying.
🟡 Turmeric Powder – Adds a golden or orange hue with anti-inflammatory benefits.
💚 Spirulina Powder – Gives a vibrant green tint and is rich in skin-loving antioxidants.

💡 How to Add Natural Colorants:

  • Start with ¼ teaspoon per 8 oz of soap, then adjust as needed.
  • Stir thoroughly to ensure even coloring.

 

3. Moisturizing Additives

If you want to make your liquid Castile soap extra hydrating, add natural moisturizers that nourish the skin.

Best Moisturizing Additives:

🌿 Aloe Vera Gel – Hydrates and soothes irritated skin.
🌼 Chamomile Extract – Calms sensitive skin and reduces redness.
🥛 Oat Milk – Provides deep moisture and is perfect for dry or eczema-prone skin.

💡 How to Add Moisturizers:

  • Add 1-2 tablespoons per 16 oz of soap after dilution.
  • Stir well and shake before each use.

 

4. Thickening Your Liquid Castile Soap

Since homemade Castile soap is naturally thin and watery, you can use natural thickeners to achieve a more commercial-like consistency.

Thickening Agents & Methods:

🧂 Salt Solution (Brine Method)

  • Dissolve ½ teaspoon of salt in 2 tbsp warm water.
  • Slowly stir into the soap to thicken (don’t overdo it—too much can make the soap separate).

🌿 Xanthan Gum or Guar Gum

  • Blend ¼ teaspoon per 8 oz of soap to create a smooth, silky consistency.
  • Dissolve in a small amount of glycerin or water before adding to prevent clumps.

💡 Pro Tip: Add thickeners gradually to avoid making the soap too gelatinous.

 

Key Takeaways from This Lesson

✅ Essential oils add natural fragrance and skin benefits—lavender for calming, tea tree for antibacterial properties.
✅ Natural colorants like activated charcoal, turmeric, and spirulina give your soap a unique, chemical-free look.
✅ Moisturizing additives like aloe vera, chamomile, and oat milk enhance hydration and skin nourishment.
✅ Natural thickeners like salt, xanthan gum, and guar gum adjust the consistency for a richer lather.

 

Next Lesson: Testing & Using Your Liquid Castile Soap

Now that you’ve customized your soap, it’s time to test its pH, troubleshoot common issues, and explore different uses!

🔹 How to test pH levels for safety
🔹 Fixing common soap-making mistakes
🔹 Creative ways to use your liquid Castile soap

➡️ See you in the next lesson! 🎉

Step-by-Step Liquid Castile Soapmaking

Step-by-Step Liquid Castile Soapmaking

Now that we have our tools, safety precautions, and ingredients ready, it’s time to make liquid Castile soap! This process involves saponification, cooking the soap paste, diluting it, and adjusting the final consistency. Follow these steps carefully to create a smooth, high-quality liquid soap.

 

Step 1: Preparing Your Work Area

Before you start, set up your workspace to ensure a smooth and safe soap-making experience.

✅ What to Do:

✔️ Gather all tools and ingredients ahead of time.
✔️ Wear safety gear – gloves, goggles, and long sleeves to protect against lye burns.
✔️ Work in a well-ventilated area to avoid inhaling fumes when mixing the lye solution.
✔️ Use dedicated soap-making equipment (no food use afterward).

💡 Pro Tip: Cover your work area with newspaper or a silicone mat to make cleanup easier.

 

Step 2: Making the Lye Solution

Potassium hydroxide (KOH) must be dissolved in distilled water before mixing with oils. This step creates heat and fumes, so handle it carefully.

✅ How to Make the Lye Solution:

1️⃣ Measure out the correct amount of distilled water in a heat-resistant container.
2️⃣ Slowly add the potassium hydroxide (KOH) into the water, stirring constantly.

⚠️ NEVER add water to lye! This can cause a violent reaction.

3️⃣ Stir until the lye is fully dissolved. The mixture will heat up quickly.

4️⃣ Allow the lye solution to cool to 120-140°F (49-60°C) before mixing with oils.

💡 Pro Tip: Mix lye outdoors or under a kitchen vent hood to minimize exposure to fumes.

 

Step 3: Heating the Olive Oil

✅ How to Heat the Oil:

1️⃣ Pour olive oil into your crockpot (slow cooker).
2️⃣ Turn the heat to LOW and allow the oil to reach 120-140°F (49-60°C).
3️⃣ Use a thermometer to check the temperature.

💡 Pro Tip: Keep the lye solution and oils at similar temperatures before mixing to ensure smooth blending.

 

Step 4: Mixing the Oils and Lye

Now it’s time to combine the lye solution and olive oil to start the soap-making process.

✅ How to Mix:

1️⃣ Slowly pour the cooled lye solution into the warmed olive oil.
2️⃣ Use a stick blender to blend the mixture in short bursts.
3️⃣ Continue blending until the soap reaches “trace”—this means the mixture thickens to a pudding-like texture.

💡 Pro Tip: Avoid over-blending! Stop blending when the soap reaches light to medium trace—too much blending can make it too thick.

 

Step 5: Cooking the Soap Paste

At this stage, the soap is not yet ready to use—it must be cooked to complete the saponification process.

✅ How to Cook the Soap Paste:

1️⃣ Set the crockpot to LOW heat and cover with a lid.
2️⃣ Stir occasionally with a long-handled spoon to prevent scorching.
3️⃣ Over the next 3-4 hours, the soap will change textures: Grainy and thick → Dry and clumpy → Glossy and translucent

4️⃣ When the soap becomes shiny, gelatinous, and clear, it is fully saponified and ready for dilution.

💡 Pro Tip: Test for doneness by dissolving a small amount in warm water—if it turns milky, keep cooking; if it remains clear, it’s ready!

 

Step 6: Diluting the Soap Paste

To transform the thick soap paste into liquid Castile soap, it needs to be diluted with warm distilled water.

✅ How to Dilute the Soap Paste:

1️⃣ In a separate pot, heat 30 oz of distilled water until warm (but not boiling).
2️⃣ Slowly add the warm water to the soap paste, stirring gently to help it dissolve.
3️⃣ Cover and let it sit overnight—this allows the paste to fully dissolve into a smooth liquid soap.

💡 Pro Tip: If your soap isn’t fully dissolved by morning, gently warm it and stir again.

 

Step 7: Adjusting & Bottling

Once the soap is fully dissolved, it’s time to adjust the consistency and add optional ingredients.

✅ Adjusting the Thickness:

  • If too thick: Add more warm distilled water, a little at a time, until it reaches the desired consistency.
  • If too thin: Use a natural thickener like:
    • Salt – Dissolve ½ teaspoon in warm water and mix into soap.
    • Guar gum or xanthan gum – Blend ¼ teaspoon into the soap for a silkier texture.

✅ Adding Essential Oils (Optional):

  • Once the soap has cooled to room temperature, add essential oils for fragrance.
  • Stir well to evenly distribute the scent.

✅ Bottling & Storage:

1️⃣ Pour the finished soap into bottles or dispensers.
2️⃣ Store in a cool, dry place—liquid Castile soap can last 6-12 months.

💡 Pro Tip: Shake the bottle before each use to keep the soap well-mixed.

 

Key Takeaways from This Lesson

✅ Preparing your workspace and wearing safety gear is crucial before handling lye.
✅ Slowly mix potassium hydroxide (KOH) into water—never the other way around.
✅ Using a stick blender helps reach “trace,” which is the thickening stage before cooking.
✅ The soap paste must be cooked for 3-4 hours until it becomes glossy and translucent.
✅ Diluting the paste with warm distilled water turns it into a pourable liquid soap.
✅ Adjusting thickness and adding essential oils helps customize the final product.

Next Lesson: Testing & Using Your Liquid Castile Soap

Now that your soap is bottled and ready, let’s cover how to test the pH level, troubleshoot common issues, and explore different ways to use liquid Castile soap!

🔹 How to test pH for safe usage
🔹 Common soap-making mistakes & fixes
🔹 Creative uses for liquid Castile soap

➡️ See you in the next lesson! 🎉

Ingredients & Soap Formulation

Ingredients & Soap Formulation

Now that we have covered safety precautions and essential tools, it’s time to dive into the basic ingredients needed to make a 1-pound batch of liquid Castile soap. This recipe uses simple, natural ingredients to create a gentle, moisturizing, and multipurpose soap.

Basic Ingredients for Liquid Castile Soap (1 lb Batch)

Ingredient Weight Purpose in Soap Making
Olive Oil 500g Primary oil that creates a mild, moisturizing soap with a creamy lather.
Vegetable Glycerin 271g Helps retain moisture, increases transparency, and acts as a natural humectant.
Potassium Hydroxide (KOH – Lye) 116g The alkaline substance that reacts with the oils to create soap (saponification).

Why These Ingredients?

  • Olive oil is the traditional base for Castile soap, providing moisturizing and gentle cleansing properties.
  • Vegetable glycerin adds a natural hydrating effect, making the soap softer and more conditioning.
  • Potassium hydroxide (KOH) is used instead of sodium hydroxide (NaOH) to create a liquid soap instead of a solid bar.
  • Link To Ingredients on Amazon

💡 Pro Tip: Use high-quality, extra virgin olive oil for a gentler, skin-friendly soap. Lower-grade olive oils (like pomace) can still work but may affect the final color and texture.

Optional Additives for Customization

One of the best parts about making your own liquid Castile soap is the ability to customize it with various additives. Here are some common options:

1. Essential Oils (for Scent & Skin Benefits)

Adding essential oils enhances your soap’s fragrance and provides additional aromatherapy benefits.

🌿 Lavender – Calming and soothing for the skin
🍋 Lemon – Uplifting and great for household cleaning
🌿 Tea Tree – Antibacterial and antifungal, ideal for acne-prone skin
🌱 Peppermint – Refreshing and cooling, perfect for morning showers
🌲 Eucalyptus – Invigorating and great for congestion relief

💡 Usage Tip: Add 5-10 drops of essential oil per 8 ounces of finished soap for a mild fragrance.

2. Herbal Extracts (for Added Skin Benefits)

🌿 Chamomile extract – Soothing and anti-inflammatory
🌿 Calendula extract – Healing and great for sensitive skin
🌿 Aloe vera gel – Hydrating and cooling

💡 How to Add: Mix 1-2 tablespoons of herbal extract per pound of soap after dilution.

3. Natural Thickeners (for a Richer Consistency)

While liquid Castile soap tends to be thinner than commercial soaps, you can thicken it naturally:

🧂 Salt (Sodium Chloride) – Helps thicken soap when added in small amounts.
🌿 Guar Gum or Xanthan Gum – Natural plant-based thickeners that improve texture.

💡 How to Add: Dissolve ½ teaspoon of salt per 8 ounces of diluted soap or ¼ teaspoon of guar gum per 8 ounces for a thicker consistency.

Key Takeaways from This Lesson

✅ Olive oil is the primary ingredient in traditional Castile soap, making it gentle and moisturizing.
✅ Vegetable glycerin enhances hydration and improves transparency.
✅ Potassium hydroxide (KOH) is used to create a liquid soap instead of a bar.
✅ Optional additives like essential oils, herbal extracts, and thickeners allow for customization.
✅ Salt, guar gum, or xanthan gum can be used to adjust the soap’s thickness.

Next Lesson: Step-by-Step Soap-Making Process

Now that we have our ingredients, let’s move on to the actual soap-making process!

🔹 Measuring and mixing ingredients
🔹 Saponification and cooking the soap paste
🔹 Diluting and storing liquid Castile soap

➡️ See you in the next lesson! 🎉

Soap-Making Safety & Equipment

Before we start making liquid Castile soap, it’s crucial to have the right tools and understand proper safety measures—especially when handling potassium hydroxide (KOH). This lesson will cover the essential tools needed for soap making and critical safety precautions to ensure a safe and successful soap-making experience.

Link to Ingredients and Tools you will need for this class

Essential Tools for Liquid Castile Soap Making

Having the right tools ensures accurate measurements, proper blending, and safe handling of ingredients. Below is a list of must-have equipment for making liquid Castile soap.

1. Digital Scale

  • Why? Precise measurements are essential for soap-making chemistry.
  • Tip: Always weigh your ingredients rather than using volume measurements (e.g., cups or spoons).

2. Crockpot (Slow Cooker)

  • Used for hot process soap making, which helps speed up saponification.
  • Keeps the soap mixture at a consistent, controlled temperature.

3. Stick Blender (Immersion Blender)

  • Blends the oils and lye mixture quickly and efficiently.
  • Helps reach “trace” (the stage where oils and lye fully combine) faster.
  • Tip: Use a dedicated stick blender for soap making—do not reuse for food preparation.

4. Heat-Resistant Mixing Bowls

  • Used to hold and mix oils and lye solutions.
  • Best materials: Stainless steel, heat-resistant plastic, or tempered glass.
  • Avoid: Aluminum or non-tempered glass, as they can react with lye or shatter under heat.

5. Large Glass or Plastic Measuring Cups

  • Used for measuring liquids like water, oils, and diluted soap.
  • Tip: Choose heat-resistant plastic or glass to withstand lye solutions.

6. Long-Handled Spoon (Stainless Steel or Silicone)

  • Used for stirring the soap mixture.
  • Best materials: Stainless steel or heat-resistant silicone.
  • Avoid: Wooden spoons, as they can absorb lye and become unsafe for future use.

7. Thermometer

  • Used to check the temperature of oils and lye solution before mixing.
  • Ideal range: Oils and lye should be between 120°F – 140°F (49°C – 60°C) before combining.

8. Soap pH Strips

  • Used to test the pH level of the finished soap.
  • Ideal pH for liquid Castile soap: 9 to 10 (safe for skin but still cleansing).

9. Bottles for Storing Liquid Soap

  • Choose plastic pump bottles, glass jars, or recycled soap dispensers.
  • Tip: If using essential oils, store in dark glass bottles to preserve fragrance.

💡 Pro Tip: Save money by sourcing your soap-making tools from thrift stores, estate sales, or discount shops! Many second-hand stores carry stainless steel bowls, measuring cups, spoons, slow cookers, and stick blenders at a fraction of retail prices. Look for heat-resistant glass, stainless steel, and silicone materials, and dedicate these tools for soap-making only. Bonus: Buying second-hand is not just budget-friendly—it’s also eco-friendly! ♻️

Safety Precautions When Making Liquid Castile Soap

Soap making involves working with potassium hydroxide (KOH), which is a strong alkaline substance. Proper safety measures are essential to prevent burns, spills, and chemical reactions.

1. Proper Handling of Potassium Hydroxide (KOH)

⚠️ KOH is highly caustic and can cause severe burns if it comes into contact with skin.
✅ Always measure KOH carefully using a digital scale—never estimate.
✅ Use heat-resistant plastic or glass containers when mixing with water (avoid metal).
✅ Never touch KOH with bare hands—always wear gloves.

2. Importance of Wearing Protective Gear

🧤 Gloves: Protects hands from KOH burns and irritation.
👓 Safety Goggles: Prevents lye splashes from getting into your eyes.
👕 Long-Sleeved Shirt & Pants: Prevents lye or soap from contacting your skin.
💨 Ventilation: Work in a well-ventilated area or near an open window to avoid inhaling fumes.

3. How to Safely Mix Lye with Water

Mixing potassium hydroxide (KOH) with water generates heat and can cause dangerous reactions if not done correctly. Follow these steps to mix safely:

1️⃣ ALWAYS add KOH to water—NEVER the other way around.

  • If you pour water onto KOH, it can cause a violent reaction, producing steam and splattering.

2️⃣ Use a heat-resistant container.

  • The mixture will become very hot (up to 200°F/93°C) and may crack weak containers.

3️⃣ Mix in a well-ventilated area.

  • The reaction creates strong fumes, so keep your face away and ensure good airflow.

4️⃣ Stir gently until fully dissolved.

  • Do not inhale the fumes; they will dissipate within a few minutes.

5️⃣ Let the lye solution cool before use.

  • The ideal mixing temperature is 120°F – 140°F (49°C – 60°C).

💡 Pro Tip: Label all soap-making containers and tools “For Soap Making Only” to prevent accidental use for food.

 

Key Takeaways from This Lesson

✅ Gather all essential tools before starting to ensure smooth and safe soap making.
✅ Always use a digital scale for accurate ingredient measurements.
✅ Wear protective gear (gloves, goggles, and long sleeves) to prevent lye burns.
✅ NEVER add water to KOH—always add KOH to water to avoid dangerous reactions.
✅ Mix lye in a well-ventilated area and let it cool before combining with oils.

 

Next Lesson: The Soap-Making Process

Now that we have our tools and safety precautions in place, we’re ready to start making liquid Castile soap!

🔹 Step-by-step instructions for mixing lye and oils
🔹 Understanding “trace” and saponification
🔹 Cooking and diluting the soap paste

➡️ See you in the next lesson! 🎉

 

Liquid Castile Soap Class

 Introduction to Liquid Castile Soap

  • What is liquid Castile soap?
  • Benefits of homemade liquid soap
  • The difference between sodium hydroxide (NaOH) and potassium hydroxide (KOH)
  • Common uses: body wash, shampoo, hand soap, dish soap, household cleaning

What is Liquid Castile Soap?

Liquid Castile soap is a plant-based, biodegradable soap traditionally made from olive oil and potassium hydroxide (KOH). It originated in the Castile region of Spain and has been used for centuries as a gentle yet effective cleanser.

Unlike commercial soaps filled with synthetic detergents, Castile soap is made purely from natural oils and lye, making it non-toxic, eco-friendly, and safe for all skin types.

What Makes Castile Soap Unique?

✅ All-Natural: Free from harsh chemicals, artificial fragrances, and preservatives
✅ Multipurpose: Can be used for personal care, home cleaning, and even pet care
✅ Eco-Friendly: 100% biodegradable and safe for the environment
✅ Moisturizing & Gentle: Packed with skin-nourishing oils like olive, coconut, or jojoba

While traditional Castile soap was made solely with olive oil, modern versions may include coconut oil, avocado oil, castor oil, or hemp oil to enhance lather and cleansing properties.

  • Benefits of Homemade Liquid Castile Soap

  • Making your own liquid Castile soap at home offers a wide range of benefits compared to commercial soaps. Not only do you control the ingredients, but you also save money, reduce environmental impact, and create a product that is safe and customizable for your needs. Let’s dive into the key advantages of homemade Castile soap.

  • 1. You Control the Ingredients

  • One of the biggest advantages of making your own liquid Castile soap is the ability to choose exactly what goes into it. Unlike store-bought soaps that often contain synthetic additives, your homemade version will be pure, natural, and chemical-free.

  • Why This Matters:

  • ❌ No sulfates – Many commercial soaps contain sodium lauryl sulfate (SLS) or sodium laureth sulfate (SLES), which can strip natural oils and irritate sensitive skin.
    ❌ No parabens – Parabens are synthetic preservatives linked to potential health concerns.
    ❌ No artificial colors or fragrances – Many synthetic dyes and fragrances can trigger allergies or skin irritation.
    ✔️ Natural, skin-friendly oils – Choose oils like olive oil for moisture, coconut oil for lather, or jojoba oil for extra nourishment.
    ✔️ Essential oils for fragrance – Customize your soap with lavender, tea tree, peppermint, citrus, or eucalyptus for natural aromatherapy benefits.
  • 💡 Pro Tip: If you have sensitive skin, eczema, or allergies, making your own Castile soap allows you to avoid any potential irritants.

  • 2. Cost-Effective

  • Making liquid Castile soap at home is a budget-friendly alternative to buying high-quality natural soaps. With a few simple ingredients, you can create a large batch that lasts for months.

  • How It Saves You Money:

  • 💰 A single batch of homemade soap can last months, depending on usage.
    💰 Buying ingredients in bulk (such as olive oil and potassium hydroxide) reduces long-term costs.
    💰 No need for expensive brand-name organic soaps – your homemade version is just as good (if not better)!

  • Cost Comparison:

Product

Average Store-Bought Cost

Homemade Cost (Per Batch)

Liquid Castile Soap (16 oz)

$10 – $20

$3 – $5

Organic Body Wash (16 oz)

$12 – $25

$3 – $6

Household Cleaners

$5 – $10 per bottle

Pennies per use
    • 💡 Pro Tip: Making a large batch and diluting it for different purposes (body wash, dish soap, cleaning spray) maximizes savings.

    • 3. Environmentally Friendly

    • In addition to being natural and biodegradable, homemade Castile soap is an excellent choice for reducing plastic waste and minimizing environmental harm.

    • Eco-Friendly Benefits:

    • 🌍 Reduces plastic waste – Store your soap in reusable glass jars or recycled containers instead of buying new plastic bottles.
      🌍 No toxic runoff – Commercial soaps and detergents contain synthetic surfactants that can harm aquatic life when washed down the drain. Castile soap is biodegradable and safe for the environment.
      🌍 Sustainable ingredients – You can choose ethically sourced oils, such as organic olive oil or fair-trade coconut oil, to support eco-conscious practices.
    • 💡 Pro Tip: Use a foaming soap dispenser to stretch your soap even further and reduce water usage.

    • 4. Customizable

    • One of the most exciting aspects of homemade liquid Castile soap is the ability to tailor it to your needs. Whether you prefer a light floral scent or a rich, bubbly lather, you can tweak the formula to your liking.

    • Ways to Customize Your Soap:

    • 🛁 Scent: Add essential oils like lavender (calming), peppermint (refreshing), citrus (uplifting), or eucalyptus (invigorating).
      🫧 Foam & Texture: Adjust the oil ratios to create a richer lather or a silkier feel. Adding castor oil boosts bubbles, while olive oil creates a mild, creamy lather.
      🌿 Herbal Infusions: Steep dried herbs (such as chamomile, rosemary, or calendula) in your soap base for added skin benefits.
      💎 Color: Natural colorants like spirulina (green), turmeric (golden), or cocoa powder (brown) create beautiful, earthy hues.
    • 💡 Pro Tip: For an exfoliating effect, mix in ground oats, poppy seeds, or activated charcoal.

    • 5. Safe for Sensitive Skin

    • Many store-bought soaps contain harsh detergents that strip the skin of its natural oils, leading to dryness, irritation, or allergic reactions. Castile soap is a gentle, moisturizing alternative that works for all skin types.

    • Why It’s Great for Sensitive Skin:

    • ✔️ No synthetic detergents – Gentle enough for babies, eczema, and dry skin
      ✔️ Moisturizing oils – Natural plant-based oils hydrate rather than dry out the skin
      ✔️ pH balanced – Less likely to disrupt your skin’s natural barrier
      ✔️ Non-irritating – No artificial fragrances, colors, or harsh preservatives
    • 💡 Pro Tip: For an extra gentle formula, use only olive oil and skip essential oils to keep it unscented.

    • Key Takeaways from This Lesson

    • ✅ Homemade liquid Castile soap is free from harmful chemicals, making it a healthier option for you and your family.
      ✅ It’s budget-friendly and lasts much longer than store-bought alternatives.
      ✅ By making your own soap, you reduce plastic waste and minimize environmental impact.
      ✅ You can fully customize the scent, texture, and ingredients to suit your needs.
      ✅ Castile soap is incredibly gentle, making it safe for all skin types, including babies and those with sensitive skin.
    • Next Lesson: Soap-Making Safety & Equipment
    • Now that we’ve covered the benefits, let’s move on to the most important part—safety!
    • 🔹 Handling lye safely
      🔹 Essential equipment checklist
      🔹 Setting up your soap-making workspace

➡️ See you in the next lesson! 🎉