Casein Hydrolysis Test

We used the casein hydrolysis test to determine whether our bacteria are able to hydrolyze or digest casein, which is the major protein in milk.

First we obtained a skim milk agar plate and then we used the aseptic technique to inoculate the skim milk agar plate with a loopful of bacteria from our agar slant culture.





















We then incubated the inoculated plate upside-down at 35 degrees Celsius for two days.

After two days, we unfortunately found out that our test (on the right) was negative because after examining the plate we did not find a clear zone around our bacterial growth, which would have indicated a positive test.