Following up on my experiment with a green laser and olive oil, today I tried to make a more rigorous and repeatable setup and actually measure the reddish fluorescence with a PLOTS spectrometer. I wasn't really successful -- I need to use glass test tubes instead of plastic ones (they scatter the light far too much) and I'm not sure the light is bright enough for our instrument. I'll keep trying; maybe somehow blocking the green light inside the spectrometer would allow it to overexpose enough to get the red light.
Still, it was cool to get such an exact measurement of 532 nanometers for the green light!
Update: It's possible the tiny spike at 564 nanometers in the olive oil sample is fluorescence. It did not show up in the control. I checked the colors of each peak using this wavelength to hexadecimal color calculator and did a visual comparison to the photograph I took here, and it actually seems pretty close!
It's different from what I had described as a "reddish" color, but I wonder if my perception of the color was "colored" by its contrast to the powerful green?
Also take a look at this neat separation of red, green and blue I did in Photoshop: