Well, perhaps a buchner flask, with the yeast culture in, attached to an upturned measuring cylinder, full of water, and over water. This will be measuring CO2 production. Do for various PH levels. I suspect the use of the indicator is to check the PH buffer is at the correct PH.

A pic of possible set-up: http://herbarium.usu.edu/fungi/funfacts/respiration.jpg

I’m also working on measuring the respiration of Carbon dioxide fom yeast, but instead of using the myth as a indicator I’m using it to actually measure the carbon dioxide. If you look through the web you would find out that the more dioxide you have in something the blue myth will actually turn to a yellow color that indentifies the carbon dioxide. So if you were able to use a spectro(measuring device for light and wavelengths) you could find the differences of the carbon dioxide the yeast is producing.

Suspended flask/Graduated cylinder and tubing is how we gauged the the O2 in mL Incrimnents.

Its quite common p[ractice to use this as a means, just have about 3-4 people in your group to keep viable and accurate measurements, also test 3 times if needed and make sure they correspond with one another. Wow did they just fly past the Aspectic techniques with you kids these days? We had an hour lecture on the matter.