Chocolate agar (CHOC) or chocolate blood agar (CBA)
- Chocolate agar is a non-selective, enriched growth medium.
- It is a variant of the blood agar plate, containing red blood cells that have been lysed by slowly heating to 80 °C.
- Chocolate agar is used for growing fastidious respiratory bacteria, such as Haemophilus influenzae and Neisseria meningitidis.
- In addition, some of these bacteria, most notably H. influenza, need growth factors such NAD (factor V) and hemin (factor X), which are inside red blood cells; thus, a prerequisite to growth for these bacteria is lysis of the red blood cells. The heat also inactivates enzymes which could otherwise degrade NAD.
- The agar is named for the color and contains no actual chocolate