Brewer's yeast: A very much alive mushroom
With the mushrooms comes the wort: Only the right yeast transforms cloudy bread into tasty beer. After all, it is the fermentation process that conjures up the alcohol in the beer - and thus gives us a happy tingle on the tongue. Although the microorganisms in brewer's yeast have always played a major role in the art of brewing beer, it was not known for a long time how important they actually are for the craft of brewing. In the German Purity Law, for example, yeast is not even mentioned - it was not until the 19th century that knowledge of brewer's yeast spread.
Saccharomyces cerevisiae, as the yeast fungus is called in technical Latin, belongs to the budding yeasts. Subspecies of this yeast are used both for baking and for brewing beer. But beware! While brewer's yeast can be used to make delicious baked goods, brewer's yeast should never be used for brewing beer. The result is guaranteed to taste awful. Only pure cultured yeast can be used to brew delicious beer of consistent quality.
Brewer's yeast in brewing
When does the yeast actually get into the beer? After the brewmaster (at home or in the brewery) has prepared the so-called beer wort, brewer's yeast is added at appropriate temperatures. In this process, the malt sugar ferments into alcohol and carbon dioxide. Strictly speaking, alcohol and carbon dioxide are byproducts produced by the yeast fungus during the fermentation process. These by-products have a major influence on the taste of the beer.
Pure culture yeasts for the perfect beer taste
At Gastro Brennecke, we always offer pure cultured yeast for brewing beer. Pure cultured yeast - this means that quality and taste are consistent with these yeasts. This is not a matter of course, because yeast is dynamic and stubborn, so that only pure-breeding yeasts lead to reliable taste experiences when brewing beer.
We differentiate our pure culture yeasts into two types:
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top-fermenting brewer's yeast: it ferments at average temperatures of 15 to 20 °C. As a mnemonic, you can remember the higher fermentation temperature; however, top-fermenting yeast gets its name from the fact that it forms cell clusters during fermentation, which causes the yeast to float on top of the beer at the end of the fermentation process. Top-fermented beers include ales, kölsch, altbier, weissbier and stouts.
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bottom-fermentingbrewer's yeast: Here, too, temperatures can be used as a guide: Bottom-fermenting yeast ferments already at 4 to 10 °C. However, the name comes from the fact that the yeast settles at the bottom of the vessel after the fermentation process. Bottom-fermented beers were only able to establish themselves internationally after the spread of refrigeration and cooling machines. Bottom-fermented beer styles include lager, pilsner and märzen
In the craft beer scene, more and more young brewmasters are experimenting with different flavors to bring interesting new beers to market. Yeast is a key player in this flavor spectacle: around twenty different yeast varieties are used throughout Germany. Scientists are working to constantly expand the flavor spectrum of the countless yeast varieties.
Brewer's yeast and flavor
The exact flavor composition in beer is highly dependent on the byproducts that the yeast produces during the fermentation process. What does this mean specifically for brewing beer? Well, top-fermenting bre wer's yeast tends to produce more byproducts, which leads to increased flavor diversity in beer. One example of this is the "banana flavor" typical of wheat beer, which is produced by the esters present in the beer. Bottom-fermenting brewer's yeast, on the other hand, produces fewer by-products, so the beer's aroma is more straightforward and unclouded.
The final taste of the beer depends on the one hand on the yeast used, but can also depend on factors such as temperature, combination of different yeast cultures.
At Gastro Brennecke you will find a wide selection of bottom-fermented and top-fermented brewer's yeast. Feel free to try through to find your favorite yeast for your own personal brewing experience!