Many foods are very sensitive for oxygen, which is responsible for the deterioration of many products either directly or indirectly. In fact, in many cases food deterioration is caused by oxidation reactions or by the presence of spoilage aerobic microorganisms.
Oxygen scavengers effectively prevent oxidative damage in a wide range of food constituents such as
*oils and fats to prevent rancidity,
*both plant and muscle pigments and flavors to prevent discoloration (e.g., meat) and loss of taste and
*nutritive elements, e.g., vitamins to prevent loss of the nutritional value.
The use of oxygen scavenging packaging materials means that oxygen dissolved in the food, or present initially in the headspace, can potentially be reduced to levels much lower than those achievable by modified atmosphere packaging.
Example of oxygen scavenger: ascorbic acid. Ascorbic acid is known for its reducing properties and assumedly acts with dual function in this system, both as acidifier promoting CO2 formation and in addition as an O2 scavenger.
Ascorbic acid and ascorbates used in oxygen scavenging applications because they oxidize in air, scavenging molecular oxygen. The reaction can be accelerated by the use of transition metal catalysts and light.
The antioxidant action of ascorbic acid may also be of benefit in packaging of food products with high fat contents, slowing down lipid oxidation and development of rancid taste and odor causing quality deterioration.
Oxygen scavengers
