Toward New Polymeric Oxygen Scavenging Systems: Formation of Poly(vinyl alcohol) Oxygen Scavenger Film

摘要

Active packaging is a term that refers to the use of package to do more than merely protect the food from the outside environment. Amongst active packaging, oxygen scavengers can prevent oxidative damage to flavour and colour in a wide range of foods. They offer advantages in maintaining quality and extending shelf life. We thus present the use of a cobalt(II) complex with the ligand L-threonine as a new oxygen scavenger. This complex, in addition to its high reactivity with oxygen after water activation, can be obtained easily in large amounts and does not react with oxygen in solid state. Thus, the incorporation of the Co(Ⅱ)(L-Thr)_2 (OH_2)_2 natural complex in organic polar polymer (poly(vinyl alcohol)) by casting process was conducted. The reactivity towards oxygen of the obtained films was evaluated by oxidation kinetics monitoring using ultraviolet-visible spectrophotometry as a function of time and relative humidity. Oxygen consumption of the active film was found equal to the complex alone (2.5 mg of O_2 per gramme of complex) after water activation (90.5% relative humidity).