Purdue/2 June 2008

Began milk pH testing. pH tests will occur every four hours between the times of 8:30 AM and 4:30 PM until consumer acceptance level reaches spoiled.

Consumer acceptance will be based off of three non-iGEM team members recommendations.

A digital pH meter was used in the experiments and calibrated before each series of tests.

Three milk samples were tested to account for variability.

Initial pH tests conducted at 12:30 PM.

Sample 1: 6.79

Sample 2: 6.79

Sample 3: 6.79

Probe Calibrated in pH 4.0 and pH 7.0 buffer solution prior to sample 1 reading.

Temperature was not factored into the account, and at most affected the pH of the solution by a factor of 0.1 units.

Second reading of the day at 4:30 PM

Sample 1: 6.69

Sample 2: 6.68

Sample 3: 6.68

Probe Calibrated in pH 4.0 and pH 7.0 buffer solution prior to sample 1 reading.

Edited by Craig Barcus