Analysis of volatile flavor compounds in top fermented wheat beer by headspace sampling-gas chromatography

Headspace sampling-gas chromatography (HS-GC) coupled with an internal standard method (ISM) was developed to analyze the volatile flavor compounds in top fermented wheat beer in the laboratory. Eight compounds, i.e. acetaldehyde, N-propanol, ethyl acetate, isobutyl alcohol, isoamyl alcohol, isoamyl acetate, ethyl hexanoate and ethyl octanoate were separated and quantified. This method was validated to ensure the quality of the results: the precision was satisfactory with relative standard deviation (RSD) in the range of 1.51%-4.22%, recoveries for all the analytes ranged from 95.15% to 99.85%, and the limits of detection were in the range of 0.0002-0.024 mg/L. Results of real wheat beer samples analyzed using this method showed that the volatile compound concentrations were in the range of 0.08-99.91 mg/L. Results suggested that this method exhibited good reproducibility, selectivity and high precision, and it can be useful for the analysis of routine beer samples.