Can high heat make green beans turn brown...and are they still safe to eat?

Yes, high heat can cause green beans to turn brown due to enzymatic reactions and the breakdown of chlorophyll. This browning is often a sign of overcooking, which can affect their texture and flavor. While brown green beans are generally safe to eat, they may not be as appealing or nutritious as properly cooked ones. To maintain their vibrant color and crispness, it's best to cook them quickly at high heat or blanch them briefly before further cooking.