Many food coloring sources are water-based liquids and gels, which will not mix well with any kind of oil. This means vegetable oil and other colorless oils must be combined with oil-based food coloring in order to create myriad colors for cooking. Vegetable oil that has been colored is great for coloring food by cooking with it or incorporating it into a recipe, such as frying French fries or mozzarella sticks. As long as the foods are light-colored, they will take on a deeper or brighter color. Food items such as potatoes or panko-covered mozzarella sticks, for example, will absorb the colored vegetable oil. Look for oil-based food coloring and food coloring for chocolate; these are designed to work well with fats, including oil and cocoa butter.
Best Food Colorings for Vegetable Oil
Two of the best food colorings for vegetable oil are oil-based food coloring and food coloring for chocolate, which includes powder food coloring. Powder food coloring contains no liquid at all. As a dry ingredient, it mixes into recipes that cannot take on more liquid apart from the amount of liquid called for in the recipe.
Powder food coloring does not mix well into thick batters, doughs or icings, so it is a good option for vegetable oil. Like gel food coloring, powder food coloring develops slowly, so give it five to 10 minutes to sit and fully incorporate to see the final color before adding more powder. Powder food coloring, however, is more difficult to use, so try using oil-based food coloring first.
Oil Based Food Coloring
This is the easiest and most accessible option for coloring vegetable oil. Chefmaster's Candy Colors are among the top options for oil-based food colorings because they are specifically made to bond with oil-based ingredients like chocolate and with oils themselves. Oil-based food coloring works well for recipes and ingredients that do not mix well with water, like oil, which eliminates most liquid and gel food colorings. For example, if water is mixed with oil, the two will not combine into a homogenous solution, and chocolate will seize if it is mixed with water.
How to Color Vegetable Oil
While coloring vegetable oil is not very difficult to do with oil-based food coloring, it still calls for an extra step or two when compared with the method most cooks are familiar with when it comes to coloring batter or icing. Begin by pouring the vegetable oil in a deep, microwave-safe mixing bowl to keep the oil from splattering onto the walls of the microwave. Heat the oil for a minute and a half to increase the oil's ability to absorb the food coloring.
Begin by adding two drops of oil-based food coloring to the vegetable oil and stir the oil well to thoroughly combine. Allow the oil and oil-based food coloring mixture to sit for a couple of minutes to fully incorporate and reveal the true color of the colored oil before adding more. Using a white mixing bowl will make seeing the full color easier and show the best results. If the color is not as dark or as vibrant as you would like, continue to add one drop of coloring at a time, stirring well, then wait long enough for the color to fully develop.
Do not add more than four drops or so, because even oil-based food coloring will not fully mix into the vegetable oil. It does, however, keep the color bright. Though oil-based food coloring is great for vibrant and some darker colors, an especially dark choice of color for vegetable oil might be better achieved with powder food coloring. Keep in mind that working with powder food coloring is more difficult than oil-based food coloring, so if the desired color can be reached with oil-based food coloring, that remains the best option.