What is the principle of the spread plate technique?

The spread plate technique is used to isolate and quantify viable microorganisms in a liquid sample containing one or multiple microorganisms of the same or different species. This is done by preading a specific volume of the sample onto a suitable soldier culture medium. Each of the microorganisms will form its own distinct colony on the surface of the medium. These colonies can be visually observed and counted in CFU/mL, to assess the microbial load in the sample. After the incubation period, a successful spread plate will exhibit uniformly distributed and distinct colonies covering the entire surface of the culture medium.