How to make soap with colourful swirls| COCOÉCO blog

This cold process soap recipe is the stuff of dreams

Imagine you’ve been transported to a fantastical world where the ocean is prismatic, as if it were always reflecting the most spectacular sunset… where the swell of the sea looks like a waltzing rainbow, and the rippling tide an aquatic ballet. You lose yourself over and over in these beautiful multi-hued Celestial Waves. Thanks to a special soapmaking technique, you can recreate this dreamy world in the form of a gorgeous homemade soap!

The swirls in this soap recipe take some time to make. You have to mix up six different colours of soap batter and be sure to work at light to medium trace. But the result will be worth all your efforts—just as the recipe was worth ours! It was quite a challenge to find the right technique, to come up with a striking yet harmonious combination of colours, and then to find the right words to explain our complicated process clearly. But it’s exactly this kind of challenging project that helps us improve our skills and develop new ones. After all, that’s how we grow!

Plus, once you’ve made this DIY soap once, you’ll be forever able to dive into these mesmerizing Celestial Waves.

How to make soap with colourful swirls

Before you begin

This soap recipe is made up of six colours of soap batter that must be poured in a set order, so we recommend that you number your containers. This might seem optional, but we strongly recommend it—it will make your work much easier and help you avoid mistakes. Use labels, post-its, washable markers, or whatever technique you’d like in order to keep track of your batters.
If this swirl technique appeals to you, but you’d rather not have to make six differently coloured batters, we have good news: You can easily do it with fewer hues. The important thing is to follow the directions at step 19 at the three spots in the mold (as described in step 18). You’ll need at least two colours of batter, which will be poured into one measuring funnel pitcher (see step 15). For best results, we recommend using an even number of colours. And you can of course play with the colourants to get the hues of your choosing!

Ingredients

Sodium hydroxide solution

330 g (25.65%) demineralized water
110 g (8.55%) sodium hydroxide

Oil and butter mixture

210 g (16.32%) coconut oil
120 g (9.33%) cocoa butter
120 g (9.33%) castor oil
350 g (27.20%) olive oil

Scent

11.4 g (0.89%) fig aromatic essence
14.3 g (1.11%) lime essential oil
14.3 g (1.11%) pink grapefruit essential oil

Additives

1 teaspoon orris root powder

Colourants

Colour 1: Yellow

0.64 g (0.050%) titanium dioxide
0.4 g (0.031%) yellow oxide

Colour 2: Purple

0.13 g (0.010%) titanium dioxide
0.35 g (0.027%) light red oxide
0.45 g (0.035%) ultramarine blue
0.05 g (0.004%) yellow oxide

Colour 3: Green

0.3 g (0.023%) titanium dioxide
0.1 g (0.008%) ultramarine blue
0.6 g (0.047%) yellow oxide

Colour 4: Pink

0.6 g (0.047%) titanium dioxide
0.3 g (0.023%) light red oxide

Colour 5: Orange

0.8 g (0.062%) titanium dioxide
0.04 g (0.003%) light red oxide
0.8 g (0.062%) yellow oxide

Colour 6: Red

0.2 g (0.016%) titanium dioxide
0.7 g (0.054%) light red oxide
0.1 g (0.008%) ultramarine blue

Tools

Large Pyrex cup or high-density polyethylene (HDPE) jar for the sodium hydroxide solution (minimum capacity of 500 ml)
A jar, for weighing the sodium hydroxide
Immersion blender
Small stainless steel bowl
Hot plate or stove element
Large stainless steel bowl
Six small silicone spatulas
Regular-sized silicone spatula
Scale, accurate to 0.01 g
Scale, accurate to 1 g
Pipette
A few ramekins
Thermometer
Three measuring funnel pitchers
Six small bowls or containers, or six additional measuring funnel pitchers, to mix the six different colours
A few teaspoons
Silicone loaf mold
A clean tea towel

Personal protective gear
Something to label your containers (post-its, labels, washable marker)
Soap cutter

Good to know!

You should never change an oil or butter in a soap recipe without re-entering all your ingredients in a sodium hydroxide calculator.
The saponified oils and butters provide your homemade soap with these wonderful properties:
- Coconut oil hardens your soap, cleanses, and provides great lather.
- Cocoa butter hardens it.
- Olive oil makes this soap very mild on your skin.
- Castor oil makes the soap milder and adds stability and creaminess to the lather.
Orris root powder helps fix scents. It’s particularly useful in this soap recipe as the chosen aromatic essence and essential oils are very light. Without the orris root, your soap might lose its fragrance before it’s done curing.
This soap recipe uses a ratio of water to sodium hydroxide of 3 to 1 and is superfatted at 8% through the “lye discount” method. The ratio of water to sodium hydroxide is rather high, because the swirls take a long time to make; a higher ratio helps the batters stay sufficiently liquid throughout the recipe. Keep in mind, however, that you don’t want the batters to be too liquid or the colours will mix together.

Steps to follow

Prepare and disinfect your equipment and workspace.
Take the necessary precautions for handling sodium hydroxide safely.
Prepare the sodium hydroxide solution: Weigh the water in a Pyrex measuring cup or HDPE pot. Weigh the sodium hydroxide. Pour the sodium hydroxide into the water, mix well, and set aside to cool.
Weigh the coconut oil and cocoa butters in a small bowl. Melt gently.
Weigh the olive oil and castor oil in a large bowl.
Weigh the scents and the orris root powder in a ramekin. Mix with a spoon.
Prepare three empty measuring funnel pitchers by labeling them A, B, and C. Set them aside until step 15.
When the cocoa butter and coconut oil have melted, pour them into the bowl containing the oils from step 5. Mix using a regular-sized spatula.
Weigh the colourants, using a separate small bowl or measuring funnel pitcher for each of the six batter colours. Label each pitcher or bowl with the number for each batter colour (see the ingredients list).
Add about a tablespoon of the melted oil and butter mixture from step 7 to each measuring funnel pitcher. Disperse the colourants thoroughly using a small spatula. We recommend having one small spatula for each measuring funnel pitcher (or bowl) to avoid mixing the colours.
When the oils and butter mixture and the sodium hydroxide solution have both cooled to 30– 35°C, pour the sodium hydroxide solution into melted oils and butter. Mix with the immersion blender and the regular-sized spatula until the batter reaches light trace.
Add the scents and orris root powder. Mix again with the blender and spatula until the batter reaches light to medium trace. The soap batters must remain sufficiently fluid for your swirls to work out, but they also must have thickened just enough so that the colours won’t mix together.
Divide the soap batter evenly between the six measuring funnel pitchers (or bowls).
Mix each soap batter with the mini-spatula reserved for that batter until the colour is homogeneous.
Take measuring funnel pitchers 1 and 2, and gently and simultaneously pour the batters into measuring funnel pitcher A. You want to pour them on opposite sides of the pitcher, with colour 1 on the right and colour 2 on the left. This will yield a two-toned batter.
Repeat step 15 with measuring funnel pitcher B, by pouring colours 3 and 4 into B the same way as you did in step 15 for pitcher A. Repeat again with pitcher C, using colours 5 and 6.
Place the loaf mold with the short end (width) closest to you. Prop the opposite (short, width) end up by about 2 or 3 cm, using a folded tea towel.
Make three equidistant marks on the edge of the mold closest to you (at the ¼, ½, and ¾ marks of the short, width end of the mold). The two-toned batters will be poured at each of these markings.
Take pitcher A and gently pour it into the mold at point 1, wiggling the pitcher back and forth in small movements, quickly but gently, as you pour. Keep the spout close to point 1 to create an arch of tight, small zigzags in the mold. Pour for a total of three seconds while wiggling the pitcher, then stop and set pitcher A aside.
Take pitcher B and repeat the previous step, this time pouring at point 2. Then take pitcher C and repeat at point 3.
Continue, alternating which pitcher you pour from at which point, in the following order. When about one third of the batter has been poured, note which pitcher you last poured from before proceeding to step 22.
- Order of pours:
 - Pitcher C at point 1.
 - Pitcher A at point 2.
 - Pitcher B at point 3.
 - Pitcher B at point 1.
 - Pitcher C at point 2.
 - Pitcher A at point 3.
 - Pitcher A at point 1. (The pattern starts again from the beginning here).
 - Pitcher B at point 2.
 - Pitcher C at point 3, and so on.
When one third of the total amount of batter has been poured, gently remove the tea towel propping up the back of the mold, and carefully set the mold flat on your table or counter.
Finish filling the mold, using the same technique and following the same order as above (step 21) from the point at which you left off. Keep a little bit of batter in each measuring funnel pitcher in order to make swirls at the surface of the soap.
When the pitchers are almost empty, take pitcher A and gently pour the rest of the batter on the top of the soap, forming an S lengthwise on the surface. Repeat with pitcher B, pouring another S slightly offset from the first, then again with pitcher C, forming an S offset from the previous two.
Using the tip of your thermometer, draw many little S shapes along the width of the mold, to create a pattern from the three S shapes you just poured. Keep the tip of the thermometer close to the surface of the soap.
Wrap the sides of the mold with a tea towel and then cover the mold, making sure that whatever you use to cover the mold does not touch the soap. For example, we used a cutting board. After 72 hours, unmold the soap (wearing gloves), cut it, and leave it to cure for six to eight weeks.