How do you slow the browning of an apple?

Apple only brown due to oxidation, or the apple is being exposed to the air. To slow or even stop the browning of an apple, put it in an air-tight container, or seal all the air out.

People have said that soaking the apple in lemon juice for about 5-10 minutes will help stop the browning of the apple, but it is just an old tale, but is worth a shot.