Compact Dry LS | Listeria spp

Compact Dry LS plates provide a simple, reliable screen for Listeria spp. throughout the food-production chain—from raw materials to finished goods and environmental swabs. Each pre-sterilized dish contains selective agents and chromogens. Target organisms grow as light-blue to blue colonies, while most background flora are suppressed, giving you quick visual confirmation. Compact Dry LS streamlines Listeria monitoring, delivering clear results that keep HACCP and sanitation programs on track. Key Benefits Distinct chromogenic read-out – colored colonies are easy to spot; white/yellow colonies (non-Listeria) are ignored. Flexible 24–48 h incubation – choose 24 h for rapid release or 48 h for maximum sensitivity. Ambient-stable & stackable – store at 1 – 30 °C; low-profile plates maximize incubator space. Broad application – ideal for high-risk ready-to-eat foods, dairy, produce, seafood, and environmental monitoring programs. Incubation parameters Step Temperature Time Resuscitation (ENV) 20 °C 1 h Plate incubation 35 – 37 °C 24 ± 2 h (up to 48 ± 3 h for increased sensitivity) pH tip: Adjust the product (or 1 : 10 dilution) to pH 6 – 7 with 0.1 – 1 N NaOH (acidic) or HCl (alkaline) to ensure optimal colony development. Performance Countable range: 1 – 300 CFU per plate (1 mL inoculum). Result interpretation: blue colonies = presumptive Listeria; confirm per ISO 11290-2 if required.