Sugar Free Agar is recommended for examination of butter in accordance with International Dairy Federation. The microorganisms that do not form the normal flora of butter and other processed milk products can be grown selectively on this medium. Psychotropic and mesophilic gram-negative bacteria also grow well on this medium. Some Lancefield group D streptococci are not able to grow on this medium and hence do not interfere in the total count of the gram-negative bacteria. This medium aids differentiating non-lactic acid contaminants from lactic acid bacteria.
1. International Dairy Federation, 1964, International Standards FIL-IDF 30 2.Ritter P. and Eschmann K. H., 1966, Alimenta, 5 (2): 43 3.Thomas S. B., 1969, J. Appl. Bacteriol., 32: 269