Homemade Natural Blue Food Coloring
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Today I am sharing something that I never thought I would make: a Homemade Natural Blue Food Coloring Recipe.
Natural blue food coloring is one of the hardest colors to make naturally—but there are a few options that actually work and one of them costs very little to make.
Most of the time I try to keep things simple in the kitchen since my life is really busy, but sometimes I like to have a little extra fun with food to make our whole food/allergy-friendly kitchen more interesting, especially true when our kids were little.
But artificial food coloring is just a no go for me.
There are a few ways to make natural blue food coloring. Some work better than others depending on what you need it for.
- Red cabbage – the best DIY method (explained below)
- Blue spirulina – the most vibrant blue, great for frosting and smoothies
- Butterfly pea flower – a bright blue that changes color depending on acidity
Below, I’ll show you how to make blue food coloring at home using red cabbage, plus tips for getting the best color.
Why I Made This Blue Food Coloring
Our boys skated in a local charity hockey league and for their season finale, the team members were going to receive a cupcake decorated with frosting to match their uniforms.
It would have been simple if they'd been on a green, red, or yellow team, but blue?!
I had a good Carob Muffin recipe that I could use for healthy cupcakes and then the green source from these Mint Fat Bombs would work, and turmeric is great for yellow and beets work for pink. But blue?
I initially told my boys not to get their hopes up, but I figured something out and I think you'll love it too.
Reasons to Avoid Artificial Food Colors
We all know that those artificial food colors are not healthy. I mean, who thinks that eating something fake is good for you?
Here are some things to consider. Artificial food colorings:
- are suspected of having links to behavioral and health problems.
- can have aluminum in them. When you see, “FD & C Yellow Aluminum Lake” on an ingredient label, you can know that you will be eating aluminum. There is discussion about this form not being as toxic as other forms, but I would prefer to take no chances here.
- can contain barium or zirconium.
How to Use This Natural Blue Color
You could use this natural blue food coloring for any of the following:
- dying Easter eggs
- paper mache projects
- crafts
- fun creative food ideas (blue mashed potatoes, anyone?)
How to Make Natural Blue Food Coloring (Red Cabbage Method)
Here are the basic instructions with some process images. For the complete information, scroll to the printable recipe card.
- Boil cabbage
- Reserve water
- Add baking soda to the water
Photo 1: Reserved cabbage water.
Photo 2: The final result: homemade natural blue food coloring.
Money Saving Tip: Use filtered water for cooking the cabbage and then, though it is pretty well boiled, you can still eat the leftover veggies for dinner. Try topping them with Moroccan Vinaigrette and Chaat Masala.
Recipe Notes
- Natural food coloring is prone to fading quickly. If your color isn't that deep to begin with, you won't have much margin for fading.
- Don't try to make this blue too dark by adding a bunch of baking soda to the water if you're using it for food, or you'll end up with baking soda-flavored food.
- The color in the cabbage juice itself is not particularly sensitive to temperature, but the mixture of the baking soda with the juice is. So you will want to add the color after the food item has cooled, or else only add it to food items that will not be heated.
- If you're making frosting, note that this method creates a softer, more muted blue—blue spirulina typically will create a brighter result.
When Natural Blue Food Coloring Won't Work Well
Natural blue food coloring is very sensitive to pH:
- Acidic ingredients in your recipe (like lemon juice or yogurt) will turn it purple
- Using too much baking soda can push it toward green
- Heat can dull the color
For best results, add the coloring after cooking and use it in neutral or slightly alkaline foods.
Homemade Natural Blue Food Coloring
Ingredients
- Half-head red cabbage (yes, I said “red cabbage!”)
- Water
- Baking Soda
Instructions
- Wash the cabbage and cut out the stem.
- Chop into small pieces.
- Place cabbage pieces in a pot and add water until the cabbage is covered.
- Simmer for 10 minutes and then drain.
- The resulting liquid will be purplish (see photo #1 above).
- Gradually add baking soda, ½ teaspoon at a time, until you get a nice blue hue (see photo #2, above). Be careful, because the baking soda will add flavor to the coloring. If you are using the color for something you will be eating then you need to be especially careful how much you add. Since it is the alkaline quality of the baking soda that causes the red cabbage juice to turn blue, you can also add spinach juice, green tea, or another alkaline ingredient.
Notes
- The color in the cabbage juice itself is not particularly sensitive to temperature, but the mixture of the baking soda with the juice is. So you will want to add the color after the food item has cooled, or else only add it to food items that will not be heated.
- Natural food coloring is prone to fading quickly. And the if your color isn't that deep to begin with, you won't have much margin for fading.
- Don't try to make this blue too dark by adding a bunch of baking soda to the water if you're using it for food, or you'll end up with baking soda-flavored foo
Nutritional information is provided as a courtesy and is an estimate only. It may vary depending on ingredient brands, substitutions, and preparation methods. Optional ingredients are not included. Net carbs are typically calculated by subtracting fiber and sugar alcohols (such as erythritol) from total carbohydrates. This information should not be relied upon for medical or nutritional purposes.
Don't Feel Like DIYing?
If you'd rather not have to make your own natural blue food coloring or would like an option that will work for an acidic recipe, here is a link to a set of good natural food coloring including blue.
What will YOU use this Natural Blue Food Coloring for?
I was curious to see if blueberries would have the same chemical reaction from baking soda, so while I was making blueberry puree for pancakes tonight I gave it a shot. The liquid was indeed purple to begin with, even more obvious when put in a small white dish. I added just a bare hint of baking soda and stirred, and it turned a lovely blue color. So for those wondering if they can use blueberries, the answer is yes.
Interesting! Thanks!
I was thinking of using this as a substitute for gel coloring in hard candy (a la Breaking Bad fake meth). Once the candy is cooked and then allowed to cool and set, do you think the color would fade very quickly? I was hoping to make the candy about a week in advance and it would be stored in a container at room temperature.
I am not clear what you are asking–are you wondering if the color would fade from the candy?
Exactly 🙂
I think it would be OK. I didn’t see it fade –would love to hear.
Been looking for this all day. Thanks for the recipe 🙂
I tried the blue today using purple carrots and it worked perfectly. Chopped up the carrots and boiled them up, drained off the liquid and let it cool, then added some baking soda and voila! A dark blue liquid resulted. Added this to some icing sugar and it made a dark slate-like blue-grey, which dried to a definite blue. I am so pleased with the result, and so pleased I found out how to make my own blue colouring, as I’ve always been disappointed with the natural blue colours you buy from the supermarket here in Australia. They’ve always turned out more of a washed-out grey colour than blue. But this is brilliant! I’m so happy! My son is turning 10 next week and he’s having a ‘Despicable Me’ minions cake (actually multiple cupcake minions) so I needed a good solid blue for them, and this will be perfect!
Cool – thanks!
Oh my gosh thank you so much! How did you firgure it out?
I was searching the internet for ways to do this and found it!
Hi, I love the idea of natural food coloring. Your recipe sounds great, thanks for sharing!
But I’m a bit worried it might taste a lot like cabbage, with potatoes I can imagine it’s delish. But in a frosting? do you think that can work?
thank you so much again!
It did work. Actually the baking soda taste is the biggest potential issue. You’re welcome!
Then I shall try it tomorrow 🙂
Read the trick before but never used it.
You could dye easter egss with red onions, but I guess it would not bring out the blue 🙂
Thank you both, I will try both of those suggestions, and let you know what we find. If it doesn’t work then that’s alright, since it would be more inspiring for others to learn that they can’t color their yogurt blue! It is something most people wouldn’t know about. “Yogurt half acidic?!!!!” they would say. Oh, and Syeda, I will use those facts you gave me to put into my conclusions paragraph. And Adrienne, we will use your other recipes in the future. 🙂
Thanks. Hope to see you around again!
Hello Adrienne, we tried this experiment because I was doing a Science Fair Project about using natural coloring instead of food coloring. We figured out how to do red, orange, yellow, and purple. We thought it must be impossible to do blue or green, even as we put our minds together. Then I stumbled across this website, and thought we finally had hope. As it turns out, I was wrong. We were using yogurt as our way of testing the colors on, and we had no idea that yogurt was acidic! Therefore, we excitedly followed your directions, and this is what we saw. Without the yogurt, the mixture was blue. Then, when we added yogurt, the mixture became purple. We tried it with several different yogurts, which all failed, until I researched it, and found out that yogurt was half acidic, and half alkaline. We would not have minded, hadn’t we already made purple with blueberries. Thoroughly disappointed, I hoped to find a different way of creating blue. Would you happen to have a way for us to create blue without the yogurt turning purple? Please respond quickly, my time for the Science Fair is almost up. Although, it would be nice to hear a response from you, the ultimate reason I posted this, was so that others wouldn’t make the same mistake we did, and wouldn’t have their hopes crushed like we did. Despite all of the trouble, thank you Adrienne. 🙂
Crazy. Sorry about that. Black beans? Corn flowers?
Interesting. Yogurt is acidic because of the lactic acid it contains. To neutralize it you would have to add an alkaline substance to it first, then try the natural blue coloring. Wish I remembered more of the chemistry i studied years ago. Does it have to be yogurt? Could you use milk?
You could test the alkalinity of your yogurt with litmus paper before adding the color. Not sure what you could add to it though-some vegetable juice like cucumbers? it would have to be colorless by itself. You could try researching the alkalinity of various vegetable juices and then choose one with the least color and highest alkalinity. Hope this helps!
I am beginning to purge chemicals and toxins from foods and products, so I was very pleased to find your website– Thank you! I love the idea of using red cabbage or black beans for blue dye, but I wondered if you had tried eggplant? Since the color is deeper, I thought it might make a brighter blue…
Welcome!!! I haven’t tried it but someone just left the tip about the black beans. I am going to have to try it! They sure to make a good run at staining my counter :).