Vinegar is a common ingredient in many types of cooking. Some types of vinegar can also be used as a salad dressing. It is a common ingredient in Easter egg dyes where it is mixed with food coloring. The food coloring gives the vinegar its hue and the vinegar affects the coloring in other ways.
Vinegar Changes Color
The primary effect that adding food coloring to vinegar offers is that the vinegar changes color. This is due to the coloring agents of the food coloring. It is the same as if the coloring was added to any liquid or food. That color is diluted and spread throughout the liquid giving its color to the entire solution. Add red food coloring and your vinegar will turn red. Add green to turn it green and so on. The more food coloring you add, the more concentrated the coloring content and the brighter the colors.
Vinegar is used in making some kinds of dyes. This is most commonly done when coloring eggs for Easter. Vinegar is slightly acidic. It is in-between tomato juice and lemon juice on the pH scale with a pH of around 2.4. This allows the vinegar to react with the food coloring by breaking it down. This helps the dye maintain its color once applied to a surface such as eggshell. It also makes the dye stick better to the egg than if the coloring was used with plain water.
Effect on Vinegar
The food coloring is affected more than the vinegar. Vinegar that has had coloring added to it can still be used in normal ways such as on salads, in cooking or other uses. The vinegar will be a different color, but the chemical makeup of the coloring is mild. The changing of colors is its only affective property. The taste of the vinegar will remain unchanged as well as the smell. Of course, this is assuming that only a few drops of coloring have been used. It only takes a drop or two to color a liquid amount several times larger. If enough coloring has been used to dilute the vinegar, it can no longer be used normally.
Food coloring can be added to any type of vinegar that you may be using. If using vinegar on food, you can add food coloring to spice up the dish with a variety of colors. Salad dressing can be made brighter and more vibrant with a few drops of food coloring. Some people won't care for unnaturally colored foods though, so be careful with which foods you add colored vinegar to. You can also use red food coloring to give color to the classic vinegar volcano science project. When the acidic vinegar breaks down baking soda and begins to fizz, some red food coloring can make it look more like lava.