Calculate the pH - microbial survival and growth?
Presence of microorganisms also depends on the pH of the medium. Most bacteria grow optimally near neutral pH (optimum 6.5 - 7.5) and usually do not survive below pH 4.0. Yeasts (3- 8.5, optimum 4.0 - 6.5) and moulds (2 -11, optimum 4.5 - 6.8) can grow at more acidic pH.