I. What is Saccharomyces Pastorianus?
Saccharomyces Pastorianus is a species of yeast commonly used in the brewing industry for fermenting lager beers. It is a hybrid yeast strain that was originally classified as a separate species from Saccharomyces cerevisiae, the yeast commonly used in ale production. However, recent genetic studies have shown that Saccharomyces Pastorianus is actually a hybrid of Saccharomyces cerevisiae and another yeast species, Saccharomyces eubayanus.
II. What are the characteristics of Saccharomyces Pastorianus?
Saccharomyces Pastorianus is known for its ability to ferment at lower temperatures compared to Saccharomyces cerevisiae. This makes it ideal for brewing lagers, which require fermentation at cooler temperatures. The yeast produces clean, crisp flavors with a smooth finish, making it a popular choice for brewing light and refreshing beers.
III. How is Saccharomyces Pastorianus used in brewing?
Saccharomyces Pastorianus is typically added to the wort (unfermented beer) during the fermentation stage of the brewing process. The yeast consumes the sugars in the wort and produces alcohol and carbon dioxide as byproducts. The fermentation process can take several weeks to complete, during which time the yeast works to develop the desired flavors and aromas in the beer.
IV. What are the differences between Saccharomyces Pastorianus and Saccharomyces Cerevisiae?
One of the main differences between Saccharomyces Pastorianus and Saccharomyces cerevisiae is their optimal fermentation temperatures. Saccharomyces Pastorianus thrives at cooler temperatures, typically between 45-55°F (7-13°C), while Saccharomyces cerevisiae prefers warmer temperatures around 65-75°F (18-24°C). Additionally, Saccharomyces Pastorianus produces fewer esters and phenols compared to Saccharomyces cerevisiae, resulting in a cleaner and more neutral flavor profile.
V. What are the benefits of using Saccharomyces Pastorianus in brewing?
Using Saccharomyces Pastorianus in brewing offers several benefits, including the ability to produce lagers with a clean and crisp flavor profile. The yeast also has a high tolerance for alcohol, allowing it to ferment beers with higher alcohol content. Additionally, Saccharomyces Pastorianus is known for its flocculation properties, which helps clarify the beer by causing the yeast to settle to the bottom of the fermentation vessel.
VI. How can homebrewers incorporate Saccharomyces Pastorianus into their recipes?
Homebrewers can incorporate Saccharomyces Pastorianus into their recipes by purchasing liquid or dry yeast strains specifically designed for lager brewing. These yeast strains are typically available at homebrew supply stores or online retailers. It is important to follow the manufacturer’s instructions for rehydrating and pitching the yeast to ensure a successful fermentation. Additionally, homebrewers can experiment with different fermentation temperatures and techniques to achieve the desired flavor profile in their lagers.