Which of the following is not a method to prevent fruits from turning brown?

Immersing fruit in salt water, storing it in air-tight food bags and adding acidic juice (for example- lemon juice), all of these methods prevent the direct contact of fruit with oxygen, hence these methods can be used to prevent fruit from browning. But after cutting, if it is placed in the open air, it will be in direct contact with oxygen and due to oxidation, its natural colour will be changed to brown.