Safety Of Chilled Foods

April 2000Safety Of Chilled Foods

By: Bruce M. FloydContributing Editor

  As the U.S. food market moves increasingly toward "fresh" foods, the market for chilled foods is also growing rapidly. In the foodservice area, menu items are often partially prepared outside the restaurant, either in company-owned commissaries or by third-party processors. Some of these items are ready-to-serve, such as salad-bar items, while some need further preparation in the kitchen prior to serving. Minimal processing is the key, so that the food appears "freshly" made.

  In addition, more people are consuming convenience foods and eating in restaurants. Fewer meals are prepared from scratch, fewer people know how to cook, and home meal replacement (HMR) has made it possible to pick up dinner on the way home and reheat it in the microwave. All these factors contribute to the importance of making sure chilled foods are as safe as possible.

Clean living

  Thanks to improved processing facilities from farm to table, the cleanliness of the basic food supply has improved. The basic foods consumers eat have a longer shelf life and less filth (bugs and excreta) than in the past. Food is processed in larger plants and shipped longer distances due to advances in processing and packaging technology. Modified atmosphere packaging (MAP), other packaging advances and improved processing techniques allow significant increases in the shelf lives of perishable products.

  As the food supply has become cleaner, however, E. coli 0157:H7 and L. monocytogenes have become a general public-health problem. In other words, reducing harmless microorganisms to extend shelf life has contributed to the current food-safety problem. According to James M. Jay, Ph.D., adjunct professor, department of biological sciences, University of Nevada-Las Vegas, prior to 1982 there were only three cases of foodborne illness traceable to ground beef. "The gist of microbial interference relative to the safety of fresh foods is that a product that contains, say, 105 cells/g of harmless micro biota is less likely to allow low numbers of pathogens to proliferate than one that contains, say, 103 cells/g," he says in an article entitled "Do Background Microorganisms Play a Role in the Safety of Fresh Foods?" in the December 1997 Trends in Food Science and Technology.

  Meanwhile, the number of "at risk" people is not limited to a small percentage of the population. Listeria, for example, puts all pregnant women at risk. The government defines "at risk" people as children, the elderly, and persons with weakened immune systems, which includes those with HIV and those undergoing chemotherapy, as well as pregnant women.

  Its a good idea to test for harmful pathogens in food. Keep in mind, however, that the testing procedure must address the risks associated with a particular food and delivery system. (For more information, see "Testing for Foodborne Pathogens" in the July 1999 issue of Food Product Design.) To become acquainted with the various harmful microflora that could be living in chilled-food products, consult the FDAs Bad Bug Book, available online at http://vm.cfsan.fda.gov/~mow/ intro.html, or hire a microbiological consultant with experience in your industry.

Chilled-foods round up

  The chilled-foods category encompasses the following products: