Industry: Food and Beverage
Instrument: HT3 Static and Dynamic Headspace System
The Analysis of Commercial Beers by Dynamic Headspace
In the analysis of alcoholic beverages such as beer, there are three main categories of volatile analysis: alcohols/esters, aldehydes, and sulfur compounds. The sulfur compounds are an impurity byproduct of the fermentation process that typically requires an additional detector to the GC or at least a sulfur specific column. The unique flavors and aromas associated with foods and beverages are due to the presence of complex
combinations of volatile organic compounds. In this analysis, there is no single compound that gives a food product it’s distinctive flavor and smell, hence, the desire to have an even more comprehensive flavor profile for each product. The focus of this paper is on alcohols and esters. Largely, the chemical makeup of beer comes from its raw materials of production (i.e. malted barley, hops, and water) or during its alcoholic fermentation process; therefore it is important to be able to analyze the product prefermentation and postfermentation. In that same breath, the malt and yeast are significant characters in beer, but equally significant is the quality of both the water and hops. Regulating the alcohol levels is essential, not just because there are alcoholic content requirements, but also because they are the immediate precursors to the more flavoractive
esters. Similarly, regulating acetaldehyde levels is critical as consistently high levels could indicate poor yeast quality.
Headspace analysis of volatile compounds offers many benefits, such as simpler sample preparation and a cleaner injection technique for the GC which reduces system contamination from high concentrated samples. By incorporating EPA approved trapping techniques, the HT3 Headspace sampler is now capable of offering purge & trap analytic performance. This application note will describe the methodology and present a comprehensive compound list for each alcoholic beverage.
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