method is economical, simple in execution. Moreover, its results give specific
qualitative indicators in terms of red color isolated typical colonies of Salmonella.
We consider this method to be the productive strategy for improving the
horizontal method of Salmonella detection in milk and dairy products alongside with
other methods of safety determination (determination of the total number of
microorganisms, determination of coliform bacteria, Listeria, Staphylococcus) [5, 7,
13, 15].
The advantage of this method is reliable red color indicator sofisolated and typical
Salmonella colonies.
Such strategy of improving the horizontal method of Salmonella detection in milk
and dairy products differs from other methods by using the research suspension, which
is prepared in the ratio of 1:5 (samples of milk and dairy products in the amount of
10−11 cm
3
(d) and 50−55 cm
3
of preview concentration medium (buffered peptone
water), and further incubation of received suspension for 16±2 hours at the temperature
of 35±1 °C and subsequent selective concentration. The received culture in the quantity
of 0.06−0.07 cm
3
is transferred into test tube that contains 5.0−5.1 cm
3
RV medium
(chloride of malachite medium of green Rappaport-Vassiliadis) and 5−6 cm
3
of this
culture are also put in a flask containing 50−51 cm
3
of selenidecystine medium. These
two sawing mediums are kept in the thermostat at the temperature of 41±1 ° C for about
23±1 hours and at the temperature of 35±1 °C for about 23±1 hours. After that the
culture received two mediums is inoculated with the help of electronic circuit on the
surface of Petri cup in quantity of 2.0–2.5 cm
3
, which contains a solid selective medium
(carbolic acid red brilliant green agar-agar). And we exposure it at temperature of 35±1
°C for 23±2 hours to get isolated typical Salmonella colony of red color in terms of
changing the medium from pink to red color.
The method of coagulase-positive staphylococci detection in milk and dairy
products is aimed to develop the strategy of improving the horizontal method of
coagulase-positive staphylococci detection in milk and dairy products by changing the
quantity of research suspension.
The experiment is done with the help of research suspension, which is prepared
in the ratio of 1:5 (samples of milk and dairy products in the amount of 10−11 cm
3
(d)
and 50−55 cm
3
of selective medium of previous concentration (Giolitti-Cantoni broth
and Tween 80), followed by incubation of received suspension for 18±2 hours at the
temperature of 35±1 °C. After that the culture of received suspension in the quantity of
1.0−1,1 cm
3
is inoculated on the surface of Petri cup, which contains Beard-Parker agar
medium, by rubbing with the help of spatula of inoculumon the surface of agar. Agar
is dried in a cup with closed lid for 10−12 minutes at room temperature (20±2 °C).
Then the process of incubation takes place: a cup of Petri is put upside down at the
thermostat and is left for 24±1 and 48±1 hours at the temperature of 35±1 °C to receive
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