Refers to all microorganisms present in a sample which can tolerate the presence of oxygen and does not have specific growth requirements typically not included in the formulation of general purpose media. In accordance to Food and Drug Administration’s (FDA) regulation, Total Count is considered as one of the release parameters for food (frozen, chilled, precooked, and prepared food), pharmaceutical, and nutraceutical samples. Salmonella is a genus of Gram-negative comprised of only two (2) species, S. enterica and S. bongori. Together, they have more than 2,500 serovars, most of which are pathogenic. Historical reservoirs are birds or poultry but has been isolated in pet, reptiles, and low water activity food such as spices and flour. Based on the standard set by the Food and Drug Administration, Salmonella should be totally absent in all food and environmental samples. No tolerable level was set because it has a low infective dose that can lead to fatal diseases. Salmonella infection is caused by cross-contamination during evisceration of animal, washing and transportation of carcasses and can also occur during raw material preparation. Thus, environmental monitoring procedure should be present in industries like poultry because it is highly susceptible to the contamination.
1. Black to green isolated or fused colonies
2. Medium around the colonies changes to yellow
3. Tailing due to motility
1. No change in plate color
2. Red or reddish-purple colonies
Note: Too high Salmonella count – Plate turns completely yellow without isolated colonies; spots of fused black and green colonies are present.
- The presence of Salmonella in the sample is detected by the combination of 3 different test principles, alkalization of the medium (medium color change to yellow), greening colonies (black also), and motility of Salmonella.
- 42 ±1℃, 20 – 24hours