Determining flavors and “defects” in beer by headspace trap/gas chromatography/mass spectrometry (HStrap/GC/MS)

Analytical Session
Lee D Marotta, PerkinElmer
Co-author(s): Andrew Tipler and Tom Kwoka, PerkinElmer, USA

ABSTRACT: Beer is a popular beverage produced by the fermentation of hopped malt extracted from barley and other grains. Some compounds (flavors) have a positive effect on aroma (attributes) and some have a negative effect (defects). This presentation focuses on a new method that enables the investigation and characterization of flavors and defects of beer in one analysis using HStrap/GC/MS. Classically, this analysis is performed on four separate detectors. This new method employs one detector (MS) to provide the solutions required for the production and testing of beer. The outcome is a more cost-effective, accurate means to ensure the validity and quality control of the product. Other benefits include enhanced productivity, attaining more information from a single analysis, and requiring less bench space. The following experiments and results are discussed: quantitation of dimethyl sulfide (DMS), 2,3-butanedione (diacetyl), 2,3-pentandione, and t,2-nonenal; characterization of several types of beers; fermentation profiling; analysis of raw materials; and aging studies.

Lee Marotta has been employed by PerkinElmer LAS for 20 years as a GC, GC/MS application specialist. Throughout the years, she has helped customers select the appropriate instrumentation for their specific needs and has provided application solutions for both internal and external customers to satisfy stringent analytical requirements. PerkinElmer has provided her the opportunity to work with people in all industries who utilize the technique of gas chromatography/mass spectrometry, assisting customers with method development and troubleshooting support. In addition, she has expertise in sample introduction techniques such as thermal desorption and headspace. Prior to PerkinElmer, Lee worked at Exxon Corporate Research and Hoffman-LaRoche as a method development chemist for gas chromatography.