Aislamiento de Staphylococcus aureus por el método de Baird Parker a partir de leche en polvo.

There are many media recommended for the isolation of Staphylococcus aureus from foods, but only with some media one can obtain a good growth started with stressed cells. The Baird Parker (BP) medium is considered the best choice to recover stressed cells, however, it is not as good a medium to isolate Staphylococcus aureus from powder milk. Therefore, it is important to count with alternative media to enhance the chance for Staphylococcus aureus to grow from dehydrated products. Thirty-one powder milk samples contaminated with Staphylococcus aureus were analysed by Baird Parker method, employing four culture media: Baird Parker (BP), Baird Parker + tween + MgCl2 (BPTM), Pork plasma with bovine fibrinogen agar (PPF) and Salt Milk agar (SL). Staphylococcus aureus was isolated in SL, 38.7%; in BP, 3.2%; in BPTM, 6.4%; and PPF, 0%.