Designation for a system or a chemical reaction (artificial word from reduction and oxidation) in which a reaction partner is reductive (eg. oxygen ) and the second oxidative (eg, hydrogen). This means that the reducing agent (hydrogen) gives off electrons to the oxidant (oxygen). In the given example, water is created. With the reduction So basically it's always one too oxidation connected. Both processes together are partial reactions of a so-called redox reaction. These include many combustion and metabolic processes, such as fermentation and the photosynthesis, The wine error Mannitstich is formed by redox reaction of fructose, The wine contains both oxidative and reductive components.