Stafilokoke u mleku i problemi kontrole mleka u prometu.
1984
Mijacevic Z. | Miljkovic V.
The conditions of staphyloccoci reproduction in milk are investigated. Reproduction of Staph. aureus in milk was investigated at milk cooling temperatures determined by regulations (4'C and 10'C) and at the temperature of 250'C, i.e. the uncooled milk temperature most frequently found. Investigation of staphylococci reproduction was performed with the starting number of 102, 103 and 105/ml. At the temperature of 4 and 10'C during 9 hours the staphylococci population does not reach the number sufficient to make enterotoxin (ET) quantities provable. The same is after 48 hours. At the temperature of 25'C ET is proved in milk after 9 hours, but only with the starting contamination of 105/ml. This means that, apart from temperature, the scope of contamination with staphylococci is important for appearance of ET. Milk samples with higher starting staphylococci contamination under irregular cooling conditions make TN-ase indicative for ET after 34 and 36 hours. TN-ase and ET are not made in the milk kept 9 hours at 4'C. In milk samples kept 9 hours at 25'C TN-ase and ET are proved depending on the starting staphylococci contamination. TN-ase is proved in milk samples after 9 hours with the starting contamination of 104 or after 6 hours with the starting contamination of 105 staphylococci/ml. It is possibile to find samples in which ET is on detection level using TN-ase test.
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