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In this section: Laboratory Methods (Food)

BAM Media M91: MacConkey Agar

Media Index for BAM

January 2001

Proteose peptone or polypeptone	3 g
Peptone or gelysate	17 g
Lactose	10 g
Bile salts No. 3 or bile salts mixture	1.5 g
NaCl	5 g
Neutral red	0.03 g
Crystal violet	0.001 g
Agar	13.5 g
Distilled water	1 liter

Suspend ingredients and heat with agitation to dissolve. Boil 1-2 min. Autoclave 15 min at 121°C, cool to 45-50°C, and pour 20 ml portions into sterile 15 × 100 mm petri dishes. Dry at room temperature with lids closed.

DO NOT USE WET PLATES. Final pH, 7.1 ± 0.2.

Original Source: Bacteriological Analytical Manual, 8th Edition, Revision A, 1998.

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