Science: Cryovac

In 1937 a French scientist named Maurice Piettre, when he arrived in the U. S. for a conference on food processing, told of new wrapping material then being tried in France for refrigerated meats. The material was latex—pure natural rubber altered just enough to be workable. The trick sounded good to Dewey and Almy Chemical Co. of Cambridge, Mass., which was already using latex to make low-cost balloons ($2.25) for high-altitude meteorological and cosmic ray observation. The company's researchers set to work devising a commercial method for wrapping poultry and meat in latex.

To wrap a chicken they now stretch a latex bag over the top of a hollow metal cylinder. From the bottom air is withdrawn, sucking the bag in, until it forms a neat lining on the cylinder's walls. The chicken is popped in, air is exhausted from the bag, its mouth is closed. Then as the bag is dipped in warm water, it shrinks to fit skin-tight and almost invisible around the chicken.

Advantages claimed for this are prevention of moisture losses (hence weight losses), prevention of "freezer burns," long periods of storage for quick-frozen foods at higher (hence cheaper) temperatures. For its product Dewey and Almy has chosen the name "Cryovac," which means cold and empty.

Last week "Cryovac" bags were being tested for consumer appeal by four packing companies. A difficulty: some people have a prejudice against rubber as a food wrapper. Dewey and Almy is confident that this will be overcome, since their latex is odorless, tasteless.