3M Sensor Labels Monitor Freshness Of Refrigerated Foods

MonitorMark time-temperature labels released by 3M (St. Paul, MN) in December 1998 contain sensors that let consumers immediately see if a package of refrigerated food has been stored for the proper time at the proper temperature. The labels ensure that perishables have been treated properly from the food processor to the grocery store to the home.

Monitoring the temperature of foods is very important because temperature affects product shelf life. For example, a product that lasts for four days at 40°F may only last for four hours when exposed to 120°F—easily the temperature of a car trunk in the summer.

MonitorMark labels are temperature sensitive, changing color from off-white to black over time. The higher the temperature, the faster the label changes color. The indicator color change is irreversible, so it is easy to tell when a product has been exposed to harmful temperatures that may compromise product quality.

MonitorMark labels are applied to packages by food manufacturers during production. This black label indicates that the food has been improperly stored.

3M developed the labels in response to consumers' concerns about the temperature storage of meat and dairy products and to manufacturers' desires for cost-effective, easily applied labels. MonitorMark labels are currently available on prepackaged Cub Foods brand ground beef sold at Cub Foods supermarkets in the Minneapolis and St. Paul, MN areas.

For more information, call 651-737-6501.