Oxygen-sensitive products, packaging

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). 

One major advantage of the package is that it contains no head-space because the top seal is actually formed through a column of sterile product. This lack of headspace offers some protection, at least initially, to oxygen-sensitive products. 

An oxygen-sensitive product is packaged in a multilayer barrier pouch containing an inner EVOH layer, tie layers on either side of the EVOH, and outer layers of PR The total thickness of the PP in the film is 3 mils. Does it matter whether the structure is ... 

In cases where oxygen sensitive products are packaged, special layers providing a barrier specifically to the passage of oxygen are needed and used, in the form of co-extruded multilayered structures [17]. For the gas barrier to be successful, it should be able to ... 

Mylar M30. Used both in unsupported form, or as a component of a lamination, and can be run on both form/fill/ seal and overwrap equipment is particularly well suited for the packaging of long-shelf-life or moisture-and oxygen-sensitive products such as processed meats, salty snacks, cakes, candy, nuts, and pharmaceutical and other non-food items,... 

Example Estimate the film thickness t for a plastic pouch containing an oxygen-sensitive product, provided that not more than 5 cc of oxygen can allowed to permeate the package during six months. Assume the pouch area A = 400 cm, and the material permeability P = 165 cc micron/m day atm. 

Solution Since this is an oxygen-sensitive product, the headspace partial pressure of oxygen is near zero, Pj == 0 atm, and Ap across the package can be considered constant during the shelf hfe, therefore, Eq. 11.10 can be applied. 

Nitrogen flushing is still the major application of MAP but the level of about 0.5% oxygen is already below the economic minimum achievable and, depending on the physical form of the food, it is often desirable to achieve lower levels, especially if the aim is to avoid antioxidant or preservative use (Abe and Kondoh, 1989). Estimates of the maximum tolerable oxygen uptake by some foods for a shelf-life of 1 year at 25°C have been tabulated by Koros (1990). This varies from 1-5 ppm for instant coffee, 5-15 ppm for dried foods and snacks and 50-200 ppm for oils that normally contain antioxidant. Aseptically packaged juices and dairy products are also very oxygen-sensitive. 

Proteins are mostly hydrophilic, being very sensitive to humidity and highly soluble in water which constitutes an important limitation to their use in food packaging applications. However, some of them such as com zein, soy, or whey proteins extracted from the by-products of food industry have desirable properties as biodegradabihty and barrier power to oxygen for food packaging. In particular, com zein is obtained... 

The betalains serve as another example. They are very sensitive to different technological factors. They can only be maintained in foods with short shelf lives, produced with minimum heat treatment, and packaged in a dry state under reduced levels of light, oxygen, and humidity. Betalains have several applications in gelatin desserts, confectionery, dry mixes, poultry, dairy, and meat products. ... 

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