Occurrence of listeria monocytogenes in bulked raw milk and traditionally fermented dairy products in Uganda

Bulked raw milk, locally processed yoghurt (LPY) and Bongo, a traditionallyfermented dairy product sold at most informal milk cooling points in Uganda, were assessed for occurrence of Listeria spp. and Listeria monocytogenes. Total plate counts (TPC), holding temperature, pH and titratable acidity were also determined in all the milk products at the point of collection using standard methods. A total of 40 samples of bulked raw milk and 30 for each of LPY and Bongo were examined. Listeria spp. was higher in bulked raw milk than in fermented milk. Listeria spp.were detected in 60% of bulked raw milk, 30% of LPY and 15% of Bongo samples. Bulked raw milk had significantly higher (