Flavor changes in consumer-packaged Cheddar, processed Cheddar and Swiss cheese during refrigerated storage of the cheese were investigated. Cheddar and Swiss cheese deteriorated relatively rapidly in flavor whether or not exposed to fluorescent light, but the type of deterioration was different between light-exposed and light-protected cheese. Light-exposure tended to hasten deterioration with the development of an oxidized-type of flavor. Processed Cheddar cheese was relatively more resistant to flavor changes than natural cheese, particularly when protected from light. Generally, the rate and extent of flavor deterioration which were related directly to the size of the cheese section were individual cheese properties. Light-induced flavor changes were retarded by packaging the cheese in aluminum-laminated film or in Uvinul D 40 (a film containing an UV light screening material). Coating the cheese surface with Myvacet-700 (distilled acetylated monoglycerides) retarded flavor changes in light-protected cheese.