| 主权项 |
1. A method for distinguishing from one another, and counting, strains of lactic acid bacteria or Bifidobacteria in a known mixture, which are present in different population amounts in a dairy product, wherein the method comprises:
a) inoculating aliquots of said food product in a series of culture dishes each containing a chemically defined agar M1 medium and at least two chromogenic substrates producing different colorations, each of said substrates being taken up by at least one of said bacterial strains, and not being taken up by at least one other of said strains; and b) optionally, inoculating aliquots of said food product in a series of culture dishes containing a chemically defined agar M2 medium enabling the growth of the lactic acid bacterial strains present in the product to be tested, which strains cannot grow on the M1 medium, and at least one chromogenic substrate taken up by at least one of said bacterial strains; and c) incubating said dishes for the time necessary to form bacterial colonies, and counting the colonies for each of the colorations observed in each culture dish. |
