Beside being an ordinary fermenter, the present equipment was conceived to sample the medium, to store the samples and to record photographs of the yeasts. Ten sensors were used to measure gas exchanges. During the growth of ScM1 (a Saccharomyces cerevisiae strain) on glucose, we could observe two different linear decreases of CO2 production rates (18.17 +/- 0.12 mmol CO2 h(-2) (g biomass)(-1) and 8.67 +/- 0.12 mmol CO2 h(-2) (g biomass)(-1)), together with a sudden variation of slope during the respiro-fermentative phase.