system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do restaurants manage to keep sliced avocados green for hours, but 5 minutes after I cut mine at home, it starts to turn brown?
gpt
You coat them with something acidic to prevent the oxidation that causes the brown color. This can be lemon/lime juice (like you use in guacamole) or ascorbic acid (vitamin C) or other acidic food items. You also restrict the oxygen from getting to it by covering it with plastic wrap.