I have been dying (lol) to compare the difference between 
Wilton's
 and 
McCormick's
 black food colorings for a while now.  I decided that I would do a side by side comparison of the two food colorings in a dyeing experiment.  I knew that the food colorings contained different types of dye; both contain Blue #1 & yellow #5, Wiltons contains Red #3 and Yellow #6 whereas McCormicks contains Red #40.  
 
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| Shortly after adding the food coloring to the pot.  Wilton's is in the big pot on the left, McCormick's is in the smaller pot on the right.   | 
I added 27 g of wool fiber to each pot with 6 cups of water + 3T of white vinegar.   In the video (see the end of the post), I added black food coloring to 1/4 cup of plain water.  
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| McCormick's Black - a few minutes after adding the dye.  It is hard to tell, but there are some distinct blue and red tones mid a lot of block tones.   | 
  | 
| Wilton's Black - a few minutes after adding the dye | 
In the middle of the experiment I started to have doubts about how this was going to work out.  
Unlike my Breaking Delphinium Blue video where I added dry fiber to a pot of dye,  I wanted to add the dye to a warm pot of fiber.  I wanted to demonstrate a different way you could make dyes break.  Now, this is a technique that I KNOW works (as you can see clearly from the Wilton's food coloring samples), but I think I may have added too much black food coloring to the McCormick's so that we won't see the breaking super well.  Of course, I added the dye to the top of the pot, so the colors could be different in the bottom layers.  There is no way to know what that looks like until I wash the fiber, so I will ultimately have to wait and see.   
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| After 15 min of light simmering.  Wilton's is on the right, McCormick's is on the left. (I know, I switched orientations when I took the picture, whoops!) | 
What a difference!  The Wilton's food coloring broke into reds, purples and teal.  The McCormick's food coloring broke into a reddish brown with hints of blue.  These different blacks can be used based on what kind of breaking (or not) you hope to see in your fiber.  
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| Completed fiber: Wiltons (left) and McCormick's (right)  | 
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| Completed fiber: Wiltons (right) and McCormick's (left)  | 
Make sure you check out the video of this dyeing experiment!