advantages and disadvantages of the serial dilution agar plate technique

īoth spread and pour plate methods are commonly used for microbial enumeration of juice and wine samples. If 30 is accepted as the lowest reliable number to count and a pour plate method uses a 1.0-ml sample, it follows that the procedures described above are unsuitable for any sample that is expected to contain 100 CFU/g or mL), because only 0.1 mL of the. It is important that the number of colonies developing on the plates should be neither too large nor too small.

The plate is then incubated until the colonies appear, and the number of colonies is counted. With the pour plate method, the sample is mixed with melted agar and poured into a sterile plate. With the spread plate method, a volume of no larger than 0.1 mL is spread over the agar surface.

There are two ways of performing a plate count-the spread plate method and pour plate method. Viable Plate Count A viable cell is defined as one that is able to divide and form a colony. Vortex for 30 sec, then perform the usual pour plate method. Swab each strip thoroughly with a premoistened Ca alginate swab and place in Lecithin broth (or other suitable neutralizer). For positive control use sterile DW instead of sanitizer solution.

Advantages and disadvantages of the serial dilution agar plate technique