Recipe and instructions for how to make cold process peppermint soap with essential oil and peppermint leaves
Ah, peppermint. You’re zingy, refreshing, and oh so easy to grow. In fact, if you turn your back on it, peppermint will take over whatever space you plant it in. That’s alright though since there are so many incredible ways to use it in food, drinks, and skincare. Even natural soap! This recipe shows you how to make cold process peppermint soap using essential oil and dried peppermint leaves. They could come from your own garden or from a peppermint tea bag.
The recipe is a one-pound batch that will make five or six mint green bars with pretty flecks. The instructions are also simple and I show exactly how to make it in a video that’s shared below.
How to make Peppermint Soap
The first batch of soap I ever tried to make was natural peppermint. That first attempt didn’t go so well and I recall my frustration now nearly many years after the fact. I eventually figured out how to do it but it was difficult trying to teach myself from books. I learn so much better by seeing something done rather than reading about it — can you relate?
This first experience is one of the reasons I began offering soap making lessons. It’s also why I’ve chosen to share a Peppermint soap recipe for my very first Facebook LIVE video. You can watch that video below.
Natural Peppermint Soap Recipe
Makes 5-6 bars
454g / 1 lb batch
Technical info: superfatted at 8% and using water as 25% of the oils
The Soap Making Process
When I make handmade soap I think of the process in four main parts: Lye solution, Solid oils, Liquid oils, and everything that happens at ‘Trace’. Trace is when your oils and lye solution react and your mix begins to thicken.
Instructions for this recipe are below but you’ll find even more detailed information in my free 4-part Natural Soap Making for Beginners Series. The 40 minute video at the bottom of the page shows you exactly how this recipe is made.
‘Light Trace’ is the phase when your ingredients change from a liquidy consistency to the thickness of cake batter. ‘Medium Trace’ is when it thickens to a warm custard consistency — I generally always finish working with soap at this stage. ‘Thick Trace’ means your soap is starting to solidify and can be spooned up like thick pudding. With a thick trace you can create textured tops to your bars.
Step 1: Mix the Lye solution
Wearing gloves and eye protection and in an area with good ventilation mix the lye and water together. Pour all of the lye into the water and then mix with a stainless steel spoon until the lye crystals are dissolved. Next sprinkle in 1/8 of a teaspoon of dried peppermint leaves. These help warm up the colour of your final bars of peppermint soap. Now set the lye solution aside to cool — I like to set the jug into a basin of water to speed up the process.
Step 2: Melt the Solid oils
Some oils are solid at room temperature and need to be melted. Just after you mix your lye water begin heating your solid oils in a pan on very low heat. They will liquefy in around ten minutes but it’s better to take the oils off the heat when there are a few small pieces of solid oil still floating around. They’ll melt with a few stirs of your spoon/spatula.
Step 3: Check the Lye solution
Take the lye-peppermint-solution’s temperature with a digital thermometer. You’re aiming for it to be around 110°F / 43°C. If it’s close to that take it out of the water so it stops cooling as quickly.
Step 4: Add the Liquid oils to the Melted oils
You’ve measured all of your liquid oils into another jug. Pour about 1/4 cup of it into a small jar and add the Chromium Green Oxide. This is a mineral colour that will give you a soft green tint. Blend the mineral and oil with a milk frother. When it’s mixed pour it through a strainer and into the pan of melted oils. The strainer helps catch any particles that didn’t blend well.
Add the rest of your liquid oils to the pan and make sure to scrape the jug — Castor oil is thick and likes to stick.
Give the combined oils in the pan a good stir and take its temperature. You’re aiming for it to be within 5 degrees (Fahrenheit) of the temperature of the lye solution.
Step 5: Bring to ‘Trace’
When your temperatures are right, pour the lye-peppermint-water into the pan of oils. All in one go, no need to dawdle. Next, place your stick blender into the pan at an angle to minimize the air getting into your soap batter via the stick blender’s head.
Stir the contents of the pan gently, using the stick blender as a spoon. Then bring it into the center of the pan and while it’s at a standstill, pulse for a couple of seconds. Then gently stir. Repeat this pulse then stir process again and again until the soap thickens up to a ‘Medium Trace’ — the thickness of warm custard.
Step 6: Add Extras
At medium trace add the six drops of grapefruit seed extract, the peppermint essential oil, and the extra 1/8 tsp of dried peppermint leaves. Stir well and until all the leaves and essential oil are well blended.
Step 7: Pour into the Mold
Pour your steadily thickening peppermint soap into your mold(s), cover, and wrap with a towel. Leave for 48 hours before taking the soap out of the mold, cutting it into bars, and allowing to cure for four weeks before using. Curing means you leave it in a place that’s cool, airy, and out of direct sunlight. For full instructions on how to cure handmade soap head over here