Test of food colorants in soap – part 1

lt is not difficult to color soap. But to color it exactly the way we want is an art!

There is a lot of colors that can be used, but not all are stable under alkaline conditions of soap.

Here I tried 6 food colorants in soap – it is a very nice example of how pH affects colors.

Let’s start… I selected these, since they are easily available to me.

1. Blue
Name(s): E133 – Brilliant blue FCF (C.I. 42090)

2. Yellow
Name(s): E102- Tartrazine – FD&C Yellow 5 (C.I. 19140)

3. Red
Name(s): E124 – Ponceau 4R (C.I. 16255)

4. Orange
Name(s): E110 – FD&C Yellow 6 (C.I. 15985)

5. Green

Composition: E102- Tartrazine – FD&C Yellow 5 (C.I. 19140), E133 – Brilliant blue FCF (C.I. 42090).

6. Brown
Composition: E155 – Brown HT

I prepared soap at 30% coconut and 70% olive oil with 5% superfat.

In each pot I put 1.5g of color (containing actually only 8% – 0.12g of color together with some sugar) and mixed with 2g of glycerine to dissolve, although it was not enough.

Finally I added cca 100g of soap at half thick trace and mixed with cappuccino mixer. The color thus represented 0.12% of soap.

These are the colored soaps in trace. To make it more interesting, I put in also three pots with blue mica (INCI: CI 77891 & CI 77510 & Mica), true indigo and blue oxide (ultramarine). 

Can you guess, which is which? Leave me your tip in the comments and come back for the results in two days!