Reduction

Reduction is a chemical change in which a compound gains electrons or hydrogen, or loses oxygen, and it always occurs paired with the oxidation of another substance. In food chemistry it is the counterpart of oxidation, and managing the balance between the two is central to quality: uncontrolled oxidation causes rancidity in fats and browning in cut fruits, while controlled reduction underpins the action of antioxidants, the metabolism of fermenting yeasts and bacteria, and the behaviour of leavening and preservative systems. Analytical methods that track oxidation-reduction status help processors predict shelf life and stability.