Map-ping the future with cap-ability. (modified and controlled atmosphere food packaging)(includes related article) (Food Manufacturing and Packaging)

With consumers ranking 'fresh' as the No. 1 food concern, processors and suppliers are opening new avenues in MAP/CAP technology and applications.

The strong consumer desire for fresh and minimally processed foods has put Modified and Controlled Atmosphere Packaging (MAP and CAP) at the forefront of today's packaging research and technical achievements. Fresh meats, cut vegetables and whole fruits are being transported, stored and packaged with altered atmospheres. Some reports now indicate that the volume of foods packaged under modified atmosphere (MA) exceed aseptic, retort pouch and hot-fill packaging combined.

A few of the beneficial effects include delaying bloom in red meat and poultry, the ability to provide fresh apples and pears all year-round and extending the shelf life of cheese, fresh refrigerated pasta and fish. Expanding distribution areas through elimination of insects from freshly harvested vegetables has also been successful through MAP.

GAS OPTIONS

Three gases are generally used throughout the food industry to modify the internal package atmosphere; nitrogen (|N.sub.2~), carbon dioxide (C|O.sub.2~) and oxygen (|O.sub.2~). The trick to doubling or even tripling product shelf life is determining the optimum combinations and concentrations of these gases. Each gas serves a specific purpose.

|N.sub.2~ is an inert gas often used in combination with other MA gases as a filler. Atmospheres of 100% |N.sub.2~ equate to vacuum packaging for maintaining meat's pre-bloom color characteristics. Products such as snack foods and nuts also do well in |N.sub.2~-flushed packaging.

C|O.sub.2~ gas adds bacteriostatic and fungistatic properties to packages. Generally 20% to 40% C|O.sub.2~ is used in MAP. Gas levels less than 20% tend not to inhibit microorganism growth satisfactorily and levels greater than 40% can cause package collapse due to the fat solubility of C|O.sub.2~.

 
PRODUCTS & GASES 
 
               |O.sub.2~%      |N.sub.2~%      C|O.sub.2~% 
 
Poultry            --             70-0            30-100 
 
Red meat         60-80             --             40-20 
 
Cured meat         --             80-60           20-40 
 
Cooked meat        --             80-60           20-40 
 
Fish (oily)        --             60-40           40-60 
 
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