**5. Culture and identification methods of** *Salmonellas*

For identification of various samples, methods which alternate and support each other. These are:


138 Salmonella – A Dangerous Foodborne Pathogen

broken from the wide edge by a sterile holder. The content is transferred into a sterile beaded jar. Egg white and yolk are mixed by shaking well. Microorganisms are searched by

There are various methods for bacterial analysis in the milk. The most used methods include alive bacteria count in petri plate, direct microscope count, coliform bacteria detection, methylene blue assay, phosphatase assay, turbidity assay and assay for special bacteria

The milk which will be drunk should not include bacteria more than 30,000 and coliform bacteria in 0,1 cm3. 0,01 cm3 of pasteurized milk should not include any coliform bacteria and its pasteurization should be understood by phosphatase assay. Turbidity assay should

The milk which was milked in the morning is kept waiting 9 to 11 hours in the shadow and the milk which was milked at night is kept waiting until the next day. Other samples are tried immediately when they come to the laboratory. Milk that analysis is not performed

2. Fruit juices ( fruit juices including alcohol less than 5 g/1 and SO2 less than 10 mg/1) 3. Fruit juice concentrates (concentrates which were condensed and partially canned and

Mineral water including carbonic acid is microbiologically safe water. They lat for a long

As fruit juices are acidic and sugared foods; yeasts, molds and milk acid bacteria cause spoiling. Microbiological spoiling in fruit juice concentrates is very less. Abovementioned microorganisms also spoil concentrates. Yeasts (Candida saccharomyces, torolopsis species), milk acid bacteria (leuconostoc, lactobacillus species) in lemonades, sodas and cokes cause

1. BEVERAGE BOTTLES ARE TAKEN UNDER ASEPTIC CONDITIONS. Bottle of beverages with carbonic acid is opened 1 hour before, it is heated slightly and the gas

2. Dilutions are prepared if necessary. (from intense textured beverages and concentrates)

4. If there are membrane filters, 100 ml of sample is filtered via water squinch and the

6. Same amount of sample is added into tubes including selenite f medium which was prepared with one portion concentrate. After waiting at 37°C for 24 hours, planting is performed from every tube to SS agar. Furthermore, one cm3 each from tubes are taken and mixed with bismuth sulphide agar and poured into petri plates. When reproduction occurs, it is searched whether it is from *Salmonella* group. (551,602,611)

planting into various mediums.

be positive in sterilized milk.

1. Water (mineral water etc.)

search. These methods are applied to various milks.

immediately may be stored at refrigerator for 24 hours at most.

is drunk by diluting, basic substances and essence)

time. Some microorganisms may exist in them.

**4.10 Microbiological examination of fruit juices and other soft drinks**  Main soft drink is water. These beverages may be classified as follows.

4. Beverages including carbonic acid (lemonades, soda pops, cokes)

Examination of the samples are performed according to the following steps.

3. Samples are planted into or on the medium as 1,0 ml or 0,1 ml.

5. Plates are incubated at 30-32°C for 3 to 5 days and evaluated.

membrane filter is placed on the medium.

**4.9 Milk** 

spoiling.

PROCESS

moves out.

