61. Utilizing gas chromatography with time-of-flight mass spectrometry to monitor the aging process in bottled beer

Elizabeth Humston-Fulmer (1), Joseph Binkley (1), Gail Harkey (1) ; (1) Leco Corporation, Saint Joseph, MI, U.S.A.

Technical Session 17: Beer Aging
Tuesday, August 16  •  3:30–5:15 p.m.
Plaza Building, Concourse Level, Governor’s Square 14

Chemical analysis of the aroma analytes associated with a product or process can provide useful information for understanding a sample and are a good complement to other traditional analyses such as sensory panel information. Here, we investigate the chemical changes associated with the aging process of bottled beer. Fresh control samples were stored appropriately, while aging was accelerated for other bottles of the same sample with storage at elevated temperatures to generate simulated aged samples. Fresh samples and the samples effectively aged for different durations of time were analyzed side-by-side using headspace solid-phase microextraction (HS-SPME) as a sample preparation method. This technique collects and concentrates volatile and semi-volatile analytes in the headspace of each sample just prior to analysis. Gas chromatography coupled with time-of-flight mass spectrometry (GC-TOFMS) was then employed for chemical analysis. GC-TOFMS is a non-targeted analytical technique that provides comprehensive data that can be mined for specific target analytes of interest and also reviewed for inherent trends and differences in the data without specifying target analytes in advance of acquisition. From these data, specific time course trends were observed and the associated analytes were identified through library searching of the full mass range spectral data.

Elizabeth Humston-Fulmer received her B.S. degree in chemistry from the University of Pittsburgh and her Ph.D. degree in analytical chemistry from the University of Washington. She currently works at Leco and uses GC-TOFMS and GC×GC-TOFMS for a variety of food and beverage analyses.