Oxygen scavenging packaging

Concern for personnel exposure to hydrazine has led to several innovations in packaging to minimize direct contact with hydrazine, eg, Olin s E-Z dmm systems. Carbohydrazide was introduced into this market for the same reason it is a soHd derivative of hydrazine, considered safer to handle because of its low vapor pressure. It hydrolyzes to release free hydrazine at elevated temperatures in the boiler. It is, however, fairly expensive and contributes to dissolved soHds (carbonates) in the water (193). In field tests, catalyzed hydrazine outperformed both hydrazine and carbohydrazide when the feedwater oxygen and iron levels were critical (194). A pubUshed comparison is available (195) of these and other proposed oxygen scavengers, eg, diethyUiydroxylarnine, ydroquinone, methyethylketoxime, and isoascorbic acid. 

Many oxygen sensitive products, including food products, electronic components, pharmaceuticals, and medical products, deteriorate in the presence of oxygen. Both the color and the flavor of foods can be adversely affected. The oxidation of lipids within the food product can result in the development of rancidity. These products benefit from the use of oxygen scavengers in their packaging (67). 

Radiation Sterilization. In addition, the method of radiation sterilization to improve the wear resistance of UHMWPE components has been modified (24). This has typically involved packaging the PE cups either in an inert gas (25), in a partial vacuum or with an oxygen scavenger (12). 

Meyer, R. I. and Jokay, L. 1960. The effect of an oxygen scavenger packet, desiccant in package system on the stability of dry whole milk and dry ice cream mix. J. Dairy Sci. 43, 844. 

Oxygen scavengers can be used to reduce the 02 content in packaged milk powder but this approach may not be cost-effective (Zimmerman et al., 1974). Another approach to reducing the 02 content in the package involves using H2 in the presence of a palladium or platinum catalyst. Although the use of several antioxidants is permitted in the manufacture of edible oils, fats and butter, their use in milk powder is prohibited. 

Another variable is the type of food in contact with the active or intelligent packaging. Here there may be liquid contact (e.g. for an oxygen-scavenging crown cork for beer), dry contact (e.g. a preservative releaser for buns) or semi-solid contact (e.g. an oxygen scavenger for processed ham). 

Akkapeddi, M.K. Kraft, T.J. Socci, E.P. Oxygen Scavenging High Barrier Polyamide Compositions for Packaging Applications. U.S. Patent 6,423,776, Jul 23,2002 Honeywell International. 

Active food packaging is a film or coating that is directly or indirectly in contact with any food surfaces to increase the shelf life or improve the quality of the packaged food. The big classifications fall under either oxygen-scavenging or antimicrobial but other upcoming types such as ethylene-scavenging, moisture absorbers, taint removers, and color and flavor enhancers have also been identified. 

Food packaging additives in the United States include slips, antistats, antioxidants, colorants, antifogs, antimicrobials, and oxygen scavengers. 

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