Will putting apple slices in water keep them from turning brown?
                                
                                
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                                    4 min read                                
                            
                                When exposed to air, the flesh of a cut apple begins to brown almost immediately due to a natural chemical process called enzymatic browning. This reaction occurs when a naturally occurring enzyme called polyphenol oxidase (PPO) reacts with oxygen, producing brown-colored melanins. The unattractive discoloration can be slowed down, but simply soaking apple slices in plain water is only minimally effective and only for a short time.