Measure Gas Volume

We would like to measure the volume of Carbon Dioxide (CO2) gas emitted from coffee beans after they have been roasted. The setup we have in mind is a measuring cylinder inverted over a water trough, the coffee beans in a conical flask, with a tube running between the flask and the cylinder to capture gas bubbles. Your task however will be to advise us on whether we should be employing a more efficient system (for example gas syringe), how to optimise this system for best results (for example how to minimise water evaporation within the measuring cylinder & CO2 solubility within the water) and how to correctly translate the results taking into consideration such things as CO2 pressure within the measuring cylinder. We would also like to monitor the rate of degassing over time, either visually through taking manual readings at set time intervals or electronically with the help of e.g. an Arduino controlled sensor. You should display a high level of competence and fluency within this field, ideally with experience of gas measurement within a commercial setting or postgraduate level. You also need to be a good communicator.