BacterChrom™ Salmonella Agar Plate

• Milk Powder Samples (Including Milk with and without Probiotics)
• • Samples weighing ≤ 25g:
• Add (x) g of the sample to 9 (x) mL of Salmonella enrichment broth (Can be used: BacterBag™ Buffered Peptone Water).
• Add Supplement Salmonella selective agent at a ratio of 1mL/10g of sample (liquid form) or 1 tablet/ 25g of sample (tablet form).
• Homogenize the sample using a microbiological sample grinder.
• Incubate at 41,5 ± 1,0°C for 16 – 24 hours.
• Take 10 μL of the enriched broth and streak it onto a BacterChrom™ Salmonella Agar
• Incubate at 37 ± 1°C for 24 ± 3 hours.
  • Samples weighing 25 – 50g:
• Add (x) g of the sample to 9 (x) mL of Salmonella enrichment broth (Can be used: BacterBag™ Buffered Peptone Water).
• Add Supplement Salmonella selective agent at a ratio of 1mL/10g of sample (liquid form) or 1 tablet/25g of sample (tablet form).
• Homogenize the sample using a microbiological sample grinder.
• Incubate at 41,5 ± 1,0°C for 16 – 22 hours.
• Take 10 μL of the enriched broth and streak it onto a BacterChrom™ Salmonella Agar
• Incubate at 37 ± 1°C for 24 ± 3 hours.
  • Samples weighing 50 – 125g, dilution ratio 1:10:
• Add (x) g of the sample to 9 (x) mL of Salmonella enrichment broth (Can be used: BacterBag™ Buffered Peptone Water) preheated to 41,5°C.
• Add Supplement Salmonella selective agent at a ratio of 1mL/10g of sample (liquid form) or 1 tablet/ 25g of sample (tablet form).
• Homogenize the sample using a microbiological sample grinder.
• Incubate at 41,5 ± 1,0°C for 18 – 24 hours.
• Take 10 μL of the enriched broth and streak it onto a BacterChrom™ Salmonella Agar
• Incubate at 37 ± 1°C for 24 ± 3 hours.
  • Samples weighing 50 – 125g, dilution ratio 1:4:
• Add (x) g of the sample to 3 (x) mL of Salmonella enrichment broth (Can be used: BacterBag™ Buffered Peptone Water) preheated to 41,5°C.
• Add CSD supplement at a ratio of 1mL/10g of sample (liquid form) or 1 tablet/25g of sample (tablet form).
• Homogenize the sample using a microbiological sample grinder.
• Incubate at 41,5 ± 1,0°C for 18 – 24 hours.
• Take 10 μL of the enriched broth and streak it onto a BacterChrom™ Salmonella Agar
• Incubate at 37 ± 1°C for 24 ± 3 hours.
  •  Food Samples ≤ 25g (Samples > 25g cannot use this method)
• Animal Feed and Pet Food Samples
  •  Samples weighing ≤ 25g
  • Samples weighing 50 – 125g (dry form):
• Production Environment Samples
  • Samples weighing ≤ 25g
• Similar to section 4.1.1.
  • Samples weighing 25 – 50g:
• Add (x) g of the sample to 9 (x) mL of Salmonella enrichment broth (e.g., Buffered Peptone Water).
• Add CSD at a ratio of 1mL/ 10g of sample (liquid form) or 1 – 2 tablets/ 25g (tablet form).
• Homogenize the sample using a microbiological sample grinder.
• Incubate at 41,5 ± 1,0°C for 16 – 22 hours.
• Take 10 μL of the enriched broth and streak it onto a BacterChrom™ Salmonella Agar
• Incubate at 37 ± 1°C for 24 ± 3 hours.

Note:

• The Salmonella enrichment medium after incubation can be stored for up to 3 days at 2 – 8°C before streaking onto agar plates (except for animal feed samples).
• The BacterChrom™ Salmonella Agar plates after incubation can be stored for up to 3 days at 2 – 8°C before reading and confirming results

RESULTS

After incubation for the required time, observe colony growth on the plate surface with the following characteristic features: colony size, color, and morphology:

• Salmonella: Pink to magenta colonies
• Escherichia coli: Colorless colonies
• Enterobacter, Klebsiella spp.: Blue-green to violet colonies
• Proteus: Colorless to brownish colonies
• Gram-positive bacteria: Inhibited