Acid Broth – CAT No: AS‑1104
 
Overview
Acid Broth is a non‑selective, low‑pH liquid medium formulated for the isolation, cultivation, and maintenance of acid‑tolerant lactic acid bacteria including Lactobacillus, Pediococcus, Leuconostoc, Oenococcus, and related genera. With a controlled acidic environment (pH 4.8–5.2), the medium inhibits Gram‑negative bacteria, Bacillus spores, yeasts, and molds, while supporting vigorous growth of lactobacilli and other aciduric species.
 
Applications
Selective enrichment of lactic acid bacteria from mixed populations
Isolation of Lactobacillus spp. from yogurt, cheese, sauerkraut, sourdough, wine, and beer
Cultivation of Oenococcus oeni in winemaking
Maintenance of acid‑tolerant starter and probiotic cultures
Testing acid resistance of bacterial isolates
 
Key Features
Low pH provides natural selectivity for aciduric organisms
Nutrient‑rich formulation supports rapid, dense growth of lactobacilli
Widely used in food microbiology and probiotic research
Cost‑effective and simple preparation
 
Composition (per liter)
Tryptone (Pancreatic Digest of Casein) – 10.0 g
Yeast Extract – 5.0 g
Glucose – 10.0 g
Tween 80 – 1.0 g (≈ 1 mL)
Dipotassium Phosphate – 2.0 g
Sodium Acetate·3H₂O – 5.0 g
Ammonium Citrate – 2.0 g
Magnesium Sulfate (MgSO₄·7H₂O) – 0.2 g
Manganese Sulfate (MnSO₄·H₂O) – 0.05 g
Final pH: 4.9 ± 0.1 at 25 °C (adjusted with lactic acid or HCl after autoclaving)
 
Preparation
Dissolve 35.25 g of basal components in 950–980 mL purified water.
Adjust volume to 1 L and mix thoroughly.
Dispense into tubes or bottles.
Autoclave at 121 °C for 15 minutes.
Cool to 50 °C, then aseptically adjust pH to 4.9 with sterile lactic acid or HCl.
Mix well before use.
Alternative: Some laboratories autoclave at pH 6.8–7.0 and lower to 4.9 aseptically after cooling.
 
Storage & Shelf Life
Dehydrated medium: Store below 30 °C, dry and protected from light.
Prepared broth: Store at 2–8 °C; use within 4 weeks.
 
Incubation
30–37 °C under microaerophilic or anaerobic conditions
Typical incubation: 24–72 hours
 
For laboratory and research use only. Not for diagnostic, therapeutic, or food applications.