An official website of the United States government.

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Survival of Food Pathogens during the 60-Day Aging Period of Hard Cheeses Made from Unpasteurized Milk


<OL><LI>Evaluate adequacy of the minimum aging period of hard cheeses made from unpasteurized milk to eliminate food pathogens. <LI>Evaluate and validate alternative/improved methods to provide the desired level of public health protection. <LI>Validate techniques to monitor and control the processing conditions used in the manufacture of hard cheeses.

More information

An evaluation of the current practice of 60-day aging of hard cheeses made from unpasteurized milk will be conducted. Research is needed to assess whether the 60-day aging process of cheese made from unpasteurized milk is adequate to eliminate foodborne pathogens. Cheddar cheese will be made from milk inoculated with food pathogens (Escherichia coli O157:H7 and Listeria monocytogenes). Food pathogen levels will be monitored during the cheese making and aging period. Heat treatment of 64.4 C for 16s in combination with 60-day aging will also be evaluated. The data will be incorporated into microbial risk assessment models to assist in determining whether this procedure provides an adequate level of public health protection.
In the event that 60-day aging is found to be inadequate to provide the appropriate level of public health protection, an evaluation of alternative control measures would assist the agency in the development of policy in this area. Validation of the effectiveness of current or alternative process control measures used in the manufacture of aged hard cheese would result in a greater assurance of a safe food supply and enhanced public confidence in these products.

Armstrong, Dave
DHHS/FDA - Center for Food Safety & Applied Nutrition
Start date
End date
Project number