Mineral oils and waxes are insensitive to oxidation or rancidity. In foods exposed to air, unsaturated fatty acids are vulnerable to oxidation and rancidity. Neutralization of these free radicals terminates the cycle of lipid oxidation that leads to rancidity. To avoid rancidity, preservatives or antioxidants are added to baby oils based on vegetable oils. Sodium nitrite is also able to effectively delay the development of oxidative rancidity. Oxidative rancidity is associated with the degradation by oxygen in the air. Detection of peroxide gives the initial evidence of rancidity in unsaturated fats and oils. The antioxidants protect the oil-rich seed from atmospheric oxygen, thereby preventing rancidity. The best test for autoxidation (oxidative rancidity) is determination of the peroxide value. This process flavors the ghee, and also produces antioxidants that help protect it from rancidity. The refined oil is clear and odorless, and resists rancidity. Nitric oxide prevents iron from breaking down the fat in the meat, thus halting rancidity. Removing the buttermilk and adding salt helps to prevent rancidity in finished butter.