STORAGE STABILITY OF INTERMEDIATE MOISTURE FOOD PROCESS CHEESE FOOD PRODUCTS

A series of intermediate moisture food processed cheese foods were made utilizing water, nonfat milk solids and propylene glycol to change the water activity to 0.81, 0.86, 0.90, 0.91 and 0.94. The stability of these cheeses was tested over a 6‐month period at room temperature. The cheeses were challenged with three molds (Aspergillus niger, Aspergillus glaucus and Penicillium roqueforti), and two pathogenic bacteria (Staphylococcus aureus and Salmonella anatum). Changes in color, texture, meltability and organoleptic acceptability were followed. The high a_w cheeses (0.90‐0.94) supported the growth of the three molds, while only the 0.94 a_w cheese food supported the growth of Staphylococcus aureus. The lower a_w cheeses (0.81 and 0.86) were stable microbiologically. However, the lowest a_w cheese was initially not acceptable in terms of the other parameters, while the 0.86 a_w cheese became unacceptable after 6‐8 wk. The IMF cheese food at a a_w 0.90 was the most acceptable, with a shelf life of about 5 months.