Why did your mayonnaise turn green or change color after making it? Find out what causes this harmless reaction, especially when using olive oil.
1 Answer
Mayonnaise can turn green or change color slightly due to a reaction between the ingredients, often caused by the breakdown of chlorophyll in the egg yolks or the presence of certain metals. This is usually harmless, but can be unappetizing.
Detailed Explanation:
The green tint in homemade mayonnaise is typically caused by a few factors. First, the egg yolks contain chlorophyll, a pigment that gives plants their green color. While present in small amounts, the chlorophyll can become more visible when the mayonnaise is emulsified and sits for a while. This is especially true if you're using eggs from hens that have been fed a diet rich in green vegetables.
Second, the acidity of the lemon juice or vinegar used in the mayonnaise can react with the chlorophyll, further enhancing the green color. This reaction is more likely to occur if the mayonnaise is stored for an extended period.
Third, trace amounts of metals, such as copper or iron, in your mixing bowl or utensils can also react with the ingredients and contribute to a slight color change, sometimes resulting in a greenish or grayish hue. While this is generally safe, it's best to avoid using metal bowls or utensils when making mayonnaise to minimize this possibility.
Pro Tip:
To minimize the chance of your mayonnaise turning green, use fresh, high-quality eggs, avoid over-processing the mixture, and store it in a glass container in the refrigerator. Using a non-reactive bowl, such as glass or plastic, can also help prevent unwanted color changes.