What is Enzymatic Browning

Enzymatic browning is the changing of color of the food into brown with the use of enzymes. Generally, polyphenol oxidase is the enzyme responsible for enzymatic browning. This enzyme or other enzymes catalyze the oxidation of phenols into quinones. However, these quinones undergo polymerization, forming melanins that can cause the brown color in fruits. Therefore, enzymatic browning in fruits and vegetables is not a favorable reaction. It may also cause undesirable heavy economic losses for growers. In addition, enzymatic browning is detrimental to fresh fruit and vegetables, including apples and potatoes, and seafood, such as shrimp.

Furthermore, enzymatic browning is beneficial for developing flavor in tea and developing color and flavor in dried fruit, including raisins and figs. However, enzymatic browning can be controlled by chemical reactions. It can also be controlled by destroying the responsible chemicals with heat. In vegetables, destroying enzymes helps to preserve the color in a process called blanching. In addition, lemon juice and other acids lowering the pH are important to preserve color in fruit.