Why eggplant turn dark on cutting?

The browning of eggplants after cutting occurs due to a natural chemical reaction. Here's a detailed explanation of the process:

When an eggplant is cut, it exposes its inner flesh to oxygen in the air. This triggers the release of an enzyme called polyphenol oxidase, which is responsible for browning reactions in many fruits and vegetables.

Polyphenol oxidase reacts with compounds called polyphenols, which are present in eggplant's flesh, particularly in the skin. This reaction leads to the formation of brown pigments known as melanin.

Melanin is the same pigment that gives human skin its color and is also found in other plant tissues. As the eggplant flesh comes into contact with more oxygen, more polyphenol oxidase is released and a larger amount of melanin is produced, resulting in the darkening or browning of the eggplant.

Additionally, the presence of chlorogenic acid in eggplant also contributes to its browning. Chlorogenic acid, when exposed to oxygen, undergoes oxidation and produces compounds that further enhance the browning reaction.

The browning process can be slowed down by certain methods, such as:

Acidic solutions: Dipping the cut eggplant pieces in acidic solutions like lemon juice or vinegar can help prevent browning. The acidic environment inhibits the activity of polyphenol oxidase.

Blanching: Briefly immersing the eggplant pieces in boiling water and then immediately cooling them in ice water (blanching) can deactivate polyphenol oxidase and reduce browning.

Antioxidant treatment: Some antioxidants, such as ascorbic acid (vitamin C), can inhibit the browning reaction by neutralizing free radicals that contribute to the oxidation process.

By employing these methods, it's possible to minimize the browning of eggplants and preserve their color for a longer time after cutting.