incubated at 30 C for 72 h ; total and faecal coliforms on Violet Red Bile Agar (VRBA) containing lactose as carbon source, incubated at 37 and 44 C, respectively, for 24 h; moulds and yeast on Sabouraud Chloramphenicol Agar, incubated at 23 C for 72 h. 2