Blue food coloring can be used to turn many different foods and beverages, like frostings, water, and cocktails, blue. While you can buy blue food coloring in any grocery store, you can also experiment with your own homemade version using red cabbage. The blue you’ll achieve with homemade food coloring will be more muted and subtle than what you can buy in the store, but if you’re looking for a fun DIY project, making homemade blue food coloring is a great choice.
Ingredients1 head red cabbage8 cups (1.9 L) water½ teaspoon (2.4 g) baking sodaStepsPart 1Part 1 of 3:Extracting the Color from Red Cabbage
1Chop the cabbage. Place an entire head of red cabbage onto a cutting board. Cut off the stem and discard it. Hold the cabbage steady with one hand, and with a large chef’s knife, roughly chop the cabbage into small chunks. The cutting doesn’t have to be precise, but smaller pieces are better because you’ll get more color from the cabbage.XRed cabbage contains anthocyanin, a purplish pigment that will dissolve in water. You can collect purple cabbage water to turn it into blue food coloring.X
2Rinse the cabbage. Transfer the cabbage pieces to a large bowl. Cover the cabbage with water and use your hand to stir the cabbage around in the water. Pour the cabbage into a colander to drain out the excess water.3Boil the cabbage in water. Transfer the cabbage to a large saucepan. Cover the cabbage with enough water to cover it completely, about 8 cups (1.9 L). Put on the lid and bring the water to a boil over medium-high heat. When the water comes to a boil, reduce the heat to medium, and continue simmering for 20 minutes.XAs the cabbage boils, the anthocyanin will leach into the water, turning it purple.
4Strain the cabbage. Remove the pot from the heat. Insert a colander into a large glass or metal mixing bowl. Pour the cabbage and the purple water into the colander. The colander will catch the cabbage, and the purple water will drain into the bowl below.XThe cabbage is cooked and ready to eat. Set it aside to cool, and then use it in soups, stews, stir fries, and other dishes.XPart 2Part 2 of 3:Turning Cabbage Water into Blue Food Coloring1Boil down the purple water. Pour the collected purple water into a medium saucepan. Bring the water to a boil over high heat, and then reduce the heat to medium-high. Continue simmering the water with the lid off for about 75 minutes to reduce the purple water. Cook the mixture until most of the water has evaporated and there’s only ½ cup (118 ml) of liquid left.XAs the liquid cooks, the water will evaporate and the liquid will reduce, leaving behind a more concentrated and more vibrant purple water.
2Let the mixture cool. When the water has reduced, remove the saucepan from the heat. Set the pan aside to cool to room temperature. This could take about 30 minutes. When the purple concentrate has cooled, pour it into a clean mason jar or other clear container.Use a clear jar so you can see the color change as you add the baking soda.3Add some baking soda. Measure ⅛ teaspoon (0.6 g) of baking soda and pour it into the jar with the purple concentrate. Stir the mixture to dissolve the baking soda in the water, and allow the bubbles to subside if necessary.The purple pigment in the cabbage reacts differently with acids and bases. In an acidic environment, the anthocyanin will become redder. When you mix the anthocyanin with an alkaline ingredient like baking soda, it will become bluer.X4Test the color. Measure ¼ cup (59 ml) of a white liquid, such as milk, soy milk, or coconut milk, into a clear glass. You can also test the color on a small amount of frosting before dyeing the entire batch. Add a few drops of the food coloring and stir to incorporate the dye into the liquid. The color will be pale, but it will give you a good idea of the blue shade you’ve achieved.XThe testing step is particularly important if you’re going to use the dye to color frosting or something similar, because the pH of the frosting will alter the color of the dye.5Add more baking soda if necessary. Continue adding baking soda in ⅛-teaspoon (0.6-g) increments and testing the color until you achieve the desired shade of blue. Don’t add more than ½ teaspoon (2.4 g) of baking soda. Otherwise, the food coloring will taste salty and metallic.XThe baking soda won’t make the color darker, but it will make the dye bluer.Part 3Part 3 of 3:Using Homemade Blue Food Coloring
1Make blue ice cream. Homemade ice cream is a fun and tasty project, and the best part is that you can completely customize the ice cream according to your taste.X Transfer the ice cream base to the ice cream maker, turn on the machine, and add the blue food coloring a few drops at a time until you achieve the desired intensity.You can also add blue food coloring to store-bought white ice cream. Portion out a serving of ice cream and set it aside to soften for a few minutes. Before serving, add several drops of blue food coloring and stir to turn the ice cream blue.
2Make blue frosting. Blue frosting is great for cupcakes and cakes, Halloween decorations, Easter treats, and much more. Make a batch of vanilla buttercream or your favorite white frosting. Before icing your treats, add several drops of food coloring and stir to combine. Add more drops if necessary until you achieve the desired color.XNote that frosting colored with homemade blue will have a much more pastel hue than with store-bought food coloring.
3Color Easter eggs. Dyeing eggs is a fun tradition to celebrate Easter. Hard boil the eggs first to help prevent cracking, and when the eggs are dry, dip them into a jar of the blue food coloring for several minutes.X Alternatively, you can paint the eggs with the dye if you want to make patterned eggs.
4Use the color to make fun cocktails. There are many different cocktails and drinks that are blue, including the blue lagoon and the blue Hawaiian. To turn your drinks blue, add 1 to 2 tablespoons (15 to 30 ml) of blue food coloring to any clear or light-colored liquids, such as water, vodka, or even milk.Many blue drinks use an alcoholic liqueur called blue curaçao for the blue coloring, but you can use your food coloring instead to make non-alcoholic versions.
5Avoid using the color for foods that will be heated. When you bake foods like cakes and cookies, chemical reactions occur when the different ingredients interact and heat up. These reactions can change the color of your dye from blue to something unexpected.You can experiment with your blue food coloring and baked goods, but be warned that the dye may react unpredictably, and could turn a brown or unpleasant color.X
6Store leftovers in the refrigerator. If you have any leftover blue food coloring, transfer it to an airtight container and keep it chilled in the refrigerator. The food coloring will last for at least 2 weeks.X
7Finished.Did you make this recipe?Leave a review
