APT Agar (All Purpose Tween Agar) – CAT: AS‑1120
High‑Performance Lactic Acid Bacteria Medium for Food Microbiology & Probiotic Research
 
Overview
APT Agar (All Purpose Tween Agar), CAT: AS‑1120, is a non‑selective, highly enriched solid microbiological medium optimized for the cultivation, isolation, and enumeration of heterofermentative lactic acid bacteria (LAB). It is especially suited for Lactobacillus, Pediococcus, Leuconostoc, and Weissella species recovered from meat products, fermented sausages, dairy, beverages, and other complex food matrices.
Originally developed by Evans & Niven (1951) and later refined by Deibel et al., APT Agar remains a reference medium in food microbiology, probiotic culture maintenance, and ISO 15214‑aligned LAB enumeration protocols.
 
Why Choose APT Agar AS‑1120?
Tween 80 supplementation provides oleic acid esters essential for fastidious lactobacilli.
Balanced formulation of tryptone, yeast extract, glucose, mineral salts, and citrate ensures robust nutrient support.
Promotes typical LAB colony morphology (small, round, smooth to rough) for reliable identification.
Proven performance in routine food quality control, probiotic research, and starter culture recovery.
 
Main Applications
Cultivation and isolation of LAB from meat, sausages, cured meats, fermented foods, and beverages
Enumeration of Lactobacillus and Pediococcus in food quality control and shelf‑life studies
Growth and maintenance of probiotic strains and starter cultures in dairy and beverage fermentation
Recovery of heterofermentative LAB strains that grow poorly on MRS Agar or Acid Broth
 
Key Features & Benefits
Highly enriched, Tween 80–supplemented formula for excellent growth of oleic acid‑dependent LAB
Supports characteristic LAB colony morphology for easier recognition and differentiation
Compatible with microaerophilic or anaerobic incubation (5–10% CO₂ or anaerobic jars)
Trusted in food microbiology workflows, including ISO 15214 reference methods for LAB in meat products
 
Typical Composition (per liter)
Tryptone – 10.0 g
Yeast Extract – 5.0 g
Glucose – 10.0 g
Tween 80 – 1.0 g (≈ 1 mL)
Sodium Chloride (NaCl) – 5.0 g
Triammonium Citrate – 2.0 g
Dipotassium Phosphate (K₂HPO₄) – 2.0 g
Magnesium Sulfate (MgSO₄·7H₂O) – 0.8 g
Manganese Sulfate (MnSO₄·H₂O) – 0.14 g
Ferrous Sulfate (FeSO₄·7H₂O) – 0.04 g
Agar – 15.0 g
Final pH: 6.7 ± 0.2 at 25 °C
 
Preparation Instructions
Suspend 51.0 g dehydrated APT Agar in 1 L purified/distilled water.
Add 1 mL Tween 80 separately if not pre‑incorporated.
Heat with agitation; boil for 1 minute until dissolved.
Avoid overheating (Tween 80 is heat‑sensitive).
Dispense into containers; autoclave at 121 °C for 15 minutes.
Cool to 45–50 °C, mix gently, and pour into sterile Petri dishes.
 
Incubation Conditions
Temperature: 30–32 °C (commonly 30 °C or 35 °C depending on strain)
Time: 48–72 hours
Atmosphere: Microaerophilic or anaerobic (5–10% CO₂ incubators or anaerobic jars)
 
Storage & Stability
Dehydrated medium: Store tightly closed below 30 °C, dry and protected from light
Prepared plates: Store at 2–8 °C, protected from light; use within 4 weeks
 
Intended Use
APT Agar CAT: AS‑1120 is intended for professional laboratory and food microbiology use only. Not for human or animal consumption, clinical diagnostic use without validation, or household applications.
 
Ideal for:
Food testing laboratories
Probiotic and starter culture producers
Academic microbiology labs
R&D facilities requiring reliable LAB recovery and enumeration