Nonenzymatic browning during storage of infant cereals

The browning indicators furosine and color were determined in infant cereals and infant cereals containing powdered milk to evaluate the utility of these parameters for monitoring storage. Studies were made on seven infant cereal samples including both gluten and gluten-free products. Samples were stored under laboratory conditions at 28degreesC for four or 16 weeks; or under modified water activity conditions at 25degreesC or 55degreesC for one, two, three, or four weeks; or under industrial conditions in air or nitrogen atmospheres at 32degreesC or 55degreesC for one, three, six, or 12 months. Furosine levels increased during the storage of infant cereals containing powdered milk under all time, temperature, and water activity (a(w)) conditions assayed, except drastic conditions (55degreesC, a(w) = 0.65). Color values increased in infant cereals with gluten (7-cereal and 8-cereal samples), regardless of milk content, when they were stored under drastic conditions (55degreesC or 25degreesC with normal or modified water activity). However, the gluten-free infant cereals (rice-corn and rice-corn-soy samples) that have a characteristic yellow color showed no increase in color during storage. The extent of the Maillard reaction was greatest in the infant cereals that included milk in their formulation.