Rapid and accurate quantitative analysis of fermentation gases by Raman spectroscopy

► Raman spectroscopy was used for determination of O2, N2, H2, CH4 and CO2. ► The Raman ratio was proportional to the pressure of the sample. ► The mole fraction was obtained by calculating the ratio of partial pressure to the total pressure. ► The mole fractions in gas mixtures can be determined by Raman spectroscopy.