The Characteristics of Saccharomyces Pastorianus (S189) Yeast

Saccharomyces cerevisiae var. diastaticus, also known as s189 , is a yeast strain that is commonly used in . This yeast is different from other strains of Saccharomyces cerevisiae because it is able to consume dextrins, which are complex sugars that other yeasts cannot break down.

S189 yeast is a top-fermenting yeast that is known for its ability to produce beers with a high level of attenuation. Attenuation refers to the degree to which the yeast consumes the sugars in the wort during fermentation. S189 yeast is able to ferment sugars that other strains of yeast cannot, resulting in a beer that is drier and more effervescent than other styles.

The ideal fermentation temperature for S189 yeast is between 68-72°F (20-22°C), althogh it can tolerate temperatures as high as 80°F (27°C). This strain of yeast is best suited for brewing Belgian-style saisons, farmhouse ales, and other light, effervescent beers.

One of the unique characteristics of S189 yeast is its ability to produce a range of fruity and spicy aromas and flavors. This yeast is known for producing notes of banana, clove, and pepper, as well as hints of citrus and tropical fruit. These flavors are often more subtle than those produced by other strains of yeast, making S189 yeast a popular choice for brewers looking to create complex, nuanced beers.

When using S189 yeast, it is important to be aware of its tendency to continue fermenting in the bottle or keg. This can result in overcarbonation and potentially dangerous levels of pressure. Brewers should take care to ensure that their beer is fully fermented and properly conditioned before packaging.

S189 yeast is a versatile strain that is prized for its ability to produce complex, effervescent beers with a range of fruity and spicy aromas and flavors. While it requires some care and attention during the fermentation and conditioning process, the end result is a beer that is sure to delight any enthusiast.

Saccharomyces Pastorianus S189 Yeast 1687875089

What Temperature Should S189 Yeast Be?

S189 yeast is best used at a temperature range of 12°C – 18°C, which is equivalent to 53.6-64.4°F. It is important to maintain this temperature range for the yeast to perform optimally and produce desirable results. It is recommended to use a thermometer to ensure that the temperature is within this range. This temperature range is ideal for achieving a fermentation rate of 80 to 120 g/hl. To summarize, the recommended temperature range for S189 yeast is 12°C – 18°C (53.6-64.4°F) for optimal results.

What Yeast Is Best For Beer Fermentation?

There are several yeast strains that can be used for beer fermentation, each with its own unique characteristics and flavor profiles. However, the most popular yeast strain for beer fermentation is Saccharomyces cerevisiae, also known as brewer's yeast. This yeast strain is well-suited for a wide range of beer styles, including ales, stouts, and porters.

Another yeast strain that is commonly used for beer fermentation is Saccharomyces pastorianus, also known as yeast. This yeast strain is responsible for the production of lager beers, including pilsners, bocks, and märzens.

In addition to these two main yeast strains, there are also other yeasts that can be used for beer fermentation, such as Brettanomyces, wich is often used to create sour beers.

Ultimately, the best yeast for beer fermentation depends on the specific beer style that is being brewed and the desired flavor profile. Brewers may experiment with different yeast strains to find the one that produces the desired results for their particular beer recipe.


S189 yeast is a bottom-fermenting yeast that is widely used in the production of various beer styles, including Pilsners, lagers, märzens, and bocks. It has a high tolerance of 9-11% and a recommended fermentation temperature range of 12°C – 18°C (53.6-64.4°F). This yeast is known for its ability to produce clean and crisp flavors in beer, with a characteristic sulphurous aroma. It is a popular choice among brewers due to its reliable performance and consistent results. So if you are planning to brew a bottom-fermented beer, s189 yeast is definitely worth considering.

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Thomas Ashford

Thomas Ashford is a highly educated brewer with years of experience in the industry. He has a Bachelor Degree in Chemistry and a Master Degree in Brewing Science. He is also BJCP Certified Beer Judge. Tom has worked hard to become one of the most experienced brewers in the industry. He has experience monitoring brewhouse and cellaring operations, coordinating brewhouse projects, and optimizing brewery operations for maximum efficiency. He is also familiar mixology and an experienced sommelier. Tom is an expert organizer of beer festivals, wine tastings, and brewery tours.