How to keep vegetables green when cooking?

When cooks and home cooks boil green vegetables like green beans or broccoli, they often add a small pinch of baking soda to the pan. It turns out that adding baking soda helps vegetables retain their green color better than without it. Why does this happen?

Vegetables are green due to the pigment chlorophyll. Each chlorophyll molecule contains a magnesium ion. Vegetables contain certain organic acids that lower the pH of the water during cooking, causing the magnesium ion to be released from the chlorophyll molecule, causing the vegetables to lose their rich green color.

A pinch of baking soda, or sodium bicarbonate, neutralizes the acid in vegetables and thus prevents the release of magnesium ions from the chlorophyll molecules, so the vegetables remain green.

But be careful: too much baking soda spoils the taste of the water and causes the vegetables to lose a lot of vitamins. And be careful not to overcook the vegetables.