Why does the avocado turn brown?

An enzyme in avocados causes the flesh to oxidize when exposed to air, turning it an unappealing brown color. This is why an avocado is often green underneath the pit but brown on the exposed surfaces surrounding it — the surface underneath the pit is protected from oxygen.Mar 14, 2014 read more

The commonly touted method of leaving the seed pit in the avocado to prevent browning does work – but only on the part of the avocado that it’s shielding from oxygen. Exposed areas of the flesh will still turn brown in time. read more

The Pit Method: Many food people claim that leaving the pit in an avocado will keep it from turning brown. Science would dictate that this is only partially true. Yes, if the pit was not detached, the flesh that stays in contact with the pit will not turn brown because it's not in contact with oxygen. read more

If the avocado you have is not Hass, an avocado may turn brown because it has been handled harshly and has become bruised. This causes the inside and outside to take on a brownish hue. When you cut an avocado, this will expose the flesh to oxygen. read more