SHITANDI A., GATHONI K.
Abstract
In many tropical conditions mixing of mastitic milk with
bulk milk may occur posing hazards that could favor growth of Enterotoxin producing
S. aureus. The study investigated the possible production of staphylococcal
enetrotoxins from mastitic isolates using commercial ELISA kits. It also determined
whether there was a risk of staphylococcal enterotoxins being produced to a
hazardous level during milk storage & transportation and evaluated the efficacy
of pasteurisation on S.aurues toxins. The production of enterotoxins was found
in 16.7 % (9 of 54 ) S.aureus isolates obtained from clinical mastitic cases.
During the storage of raw milk at 27°C, S. aurues enerotoxins started to
be detected after 10 h when the viable count was 1.1 x 106 CFU/ml. At a storage
temeprature of 10 oC no enterotoxin was detected upto 24 h incubation. Staphylococcus
aureus toxin in raw milk remained serologically detectable following batch pasteurisation
at 63oC/30min. The results suggest that the mixing of mastitic milk with bulked
milk may pose a threat to human health in tropical temperatures during transportation
of milk as S. aureus enterotoxins may be produced to a hazardous level.
Keywords:
Staphylococcus aureus, enterotoxins, mastitic milk, food safety, Kenya