GAS-PRODUCTION DURING THE STORAGE OF SWISS CHEESE

Rindless block Swiss cheese was aged for 90 days and then vacuum-packa ged into retail sized portions before gas production was examined by t he cheese during storage at 7, 12 and 17-degrees-C. Visual inspection of the cheese packages revealed that excessive gas was produced in che ese portions stored at 12 and 17-degrees-C, but cheese samples stored at 7-degrees-C produced little gas even after 28 weeks. The extent of gas production by the stored cheese was determined by measuring the di splacement of water by immersed packages of cheese. The rate of gas pr oduction within the pouches was determined and straight line relations hips were obtained when fit into the Arrhenius model indicating temper ature dependance. Changes in the levels of organic acids (lactic, acet ic and propionic) in the stored cheese were monitored throughout the s torage period. Acetic and propionic acid levels in the cheese increase d substantially as gas production increased in the cheese pouches.