SUGAR FREE AGAR

Description

Butter may be contaminated in the manufacturing process, from contaminated water sources, air or unsanitary equipment. Yeast, moulds and coliforms do not survive pasteurization and are rarely found in butter made under sanitary conditions. Estimates of the number of coliforms, yeasts and moulds or Enterococci in samples of butter taken at various stages of processing are useful in tracing the source of contamination. Sugar Free Agar is prepared as recommended by the International Dairy Federation and is based on the formulation developed by Ritter and Eschmann for the detection and enumeration of contaminating bacteria in butter and other processed dairy products. Psychrotrophic 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.