By what means can growth be detected in a broth culture?

Question

microbiology

Answer 1

the optical density of the broth can be measured using a spectrophotometer.

another possibility, if there is no spectrophotometer available, would be to centrifuge a small portion of the broth and compare the resulting pellet to centrifuged uninoculated media.

a complete answer would also include acknowledgement of the fact that measuring the optical density does not 100% prove that there are bacteria in the media, and something more dianostic such as microscopic examination or spread-plating to verify the presence of bacteria.

Answer 2

The broth will cloud, and typically the smell will change as well. The way to quantitatively test the amount of growth is to centrifuge a known quantity of the broth.

Answer 3

You can use a spectrophotometer or a Klett to get the optical density.