# Homemade Natural Liquid Castile Soap

This recipe teaches you how to make natural liquid Castile soap at home from scratch using a slow cooker or Instant Pot, saving money and ensuring natural ingredients.

- Total time: 240 min
- Language: en

## Ingredients

- 1000 grams Avocado Oil
- 210 grams Potassium Hydroxide
- 250 grams Distilled Water
- 250 grams Vegetable Glycerin
- 30 grams Peppermint Essential Oil

## Instructions

1. Weigh out 1000 grams of avocado oil into a glass beaker on a digital kitchen scale.
2. Add the weighed oil to your Instant Pot set on the slow cooker setting to medium.
3. Weigh out 210 grams of potassium hydroxide into a separate glass beaker, remembering to zero out the scale with the container first.
4. Weigh out 250 grams of distilled water into another separate glass beaker, remembering to zero out the scale with the container first.
5. Weigh out 250 grams of vegetable glycerin into the same beaker with the distilled water, remembering to zero out the scale with the water first.
6. Weigh out 30 grams of peppermint essential oil into a small beaker, remembering to zero out the scale with the container first.
7. Add the essential oil to the avocado oil in the Instant Pot.
8. In a well-ventilated area, gradually pour the potassium hydroxide into the distilled water and glycerin mixture, stirring continuously until dissolved. This is an exothermic reaction, so it will get hot.
9. Check the temperature of the potassium hydroxide solution; it should cool down to below 175°F.
10. Check the temperature of the oil in the Instant Pot; it should be between 160°F and 170°F.
11. Gradually pour the potassium hydroxide solution into the oil in the Instant Pot with vigorous mixing using an immersion blender.
12. Continue blending until the mixture reaches a thick, mashed potato-like consistency, which took 7 minutes in this video.
13. Cover the Instant Pot and cook the soap gel, stirring about every half hour, for approximately 4 hours until it becomes translucent and gel-like.
14. Test the readiness of the soap by adding a small amount of the soap gel to warm distilled water in a small jar and shaking it; if the solution becomes clear, it's ready.
15. To dilute the concentrated soap gel for storage, add distilled water to the Instant Pot with the soap gel and let it dissolve on low overnight.
16. Test the pH of the dissolved liquid soap using a pH test strip; it should be around 9.
17. Pour the liquid castile soap into glass jugs for storage.
18. To use as hand soap, fill a hand soap dispenser about a quarter full with the concentrated liquid castile soap.
19. Top off the hand soap dispenser with tap water and shake to mix.

## Equipment

- Instant Pot
- slow cooker
- digital kitchen scale
- glass beaker
- thermometer
- immersion blender
- silicone spatula
- small glass jar
- glass jugs
- funnel
- hand soap dispenser

## Tips

- For this recipe, you can use 100% pure olive oil or avocado oil as they have very similar saponification values.
- Do not forget to zero out the weight of your containers when weighing ingredients.
- The glycerin speeds up the soap-making process, so it's recommended for beginners.
- Always wear gloves and eye protection when working with potassium hydroxide, as it will burn your skin.
- When mixing water with potassium hydroxide, always add the potassium hydroxide to the water, not the other way around.
- Wait for the potassium hydroxide solution to cool down to below 175°F and the oil to be between 160°F and 170°F before mixing them.
- Use a dedicated hand mixer and spatula for soap making only, do not use them for food afterwards.
- You can test if the soap is ready by adding a small amount to warm distilled water; if the solution is clear, it's ready.
- The concentrated castile soap can be stored in glass containers in the pantry for at least a couple of years.
- When diluting the concentrated soap for hand soap, fill the container about a quarter full with soap and top it off with tap water (distilled water is no longer necessary).

## Source

- Original video: https://www.facebook.com/61551677841860/videos/1049264753674229/?mibextid=rS40aB7S9Ucbxw6v
- Recipe page: https://www.cliprecipe.com/recipe/7b361cd7-eb90-4ac2-a256-ca7a04236c14
- Extracted: 2026-06-27

Extracted from the video by Clip Recipe (https://www.cliprecipe.com). Quantities and steps are as stated or shown in the video. Site guide for agents: https://www.cliprecipe.com/llms.txt