Incidence of Toxin Producing Bacteria in Milk and Milk Products

Milk and milk products is a very good source to support the growth of microorganism. Their presence may cause health hazards. Considering its unhygienic aspects in view, the present study was undertaken to judge the occurrence of toxin producing microorganism. A good number of milk, curd, ice-cream and khoa samples supplied to Tura town (Head quarter of District West Garo Hills, Meghalaya) were assessed for their total bacterial, clostridial and staphylococal counts. Out of total clostridia and total coagulase positive staphylococcus count about twenty percent were identified as clostridium botulinam and ninety percent as staphylococcus aureus respectively. These isolates, pure and identified cultures of these organisms were incubated in litmus milk for one week for production of toxins. Heat stability of toxins were determined by heating the inoculates at 75, 85, and 100.c for five minutes. Toxicity of toxins produced by these microorganisms was tested by intra peritoneal injection and orally feeding to mice and seen that 1.5 c.c intra peritoneal injection was lethal dose. Heating of inoculates at 85.c for five minutes has partially inactivated botulinam toxin, whereas it has not effected staphylococcus enterotoxin. Heating at 100.c for five minutes has completely inactivated botulinam and partially inactivated staphylococcal enterotoxin. It can be concluded from the experimental results that the bacteriological quality of milk and milk products supplied to Tura town is very poor.