Most of the aroma and flavors from craft beer are derived from the metabolites of brewing yeasts during fermentation. The yeasts used for brewing in Taiwan are mostly imported, and limited in the use of dry yeast due to its convenient usage and storage. Because the variation of dry yeast is limited, the flavors of the craft beer brewed in Taiwan are restricted in the usage of these dry yeasts. Therefore, isolation and identification of wild yeast used for brewing in Taiwan turned out to be an essential task to explore the flavors of the craft beer. Taiwan is the so-called kingdom of fruits; therefore, various yeasts can be isolated and identified from different fruits. The wild yeasts isolated from fruits can be tamed to be the yeast for craft beer brewing to bring up the new flavors. The small molecules in the aroma of beer can be collected and identified by GC-MS. In a comparison of these molecules from beer brewed by the local isolates and the commercial strains, we can distinguish what is the difference between them and see if the local isolates can bring up the new flavors.

Brewing Yeast, Craft Beer, Beer Aroma, GC-MS