Yeast Flashcards
Discusses the function of yeast in fermentation and its impact on beer flavor.
What is the primary role of yeast in brewing?
To create alcohol.
Aside from alcohol, what significant effect can yeast have on beer?
Can impact the beer’s aroma significantly.
What is yeast?
A microorganism that has the ability to create alcohol when consuming sugar.
In additon to alcohol, what else can yeast create?
carbon dioxide
Bubbles!
What are the two main species of yeast used in brewing?
- Ale yeast
- Lager yeast
What are the time and temperature characteristics of ale yeast fermentation?
Ale yeast ferments quickly, and at relatively warmer temperatures.
As opposed to lager yeast.
What are beers fermented with ale yeasts referred to as?
ales
What are beers fermented with lager yeasts referred to as?
lagers
What are the time and temperature requirements for lager yeast fermentation?
Lager yeast ferments slower, and at relatively cooler temperatures.
As opposed to ale yeast.
Comparing ale and lager yeast strains, which has a wider range of strains?
ale yeast
This results in many variations of ales.
Between lager and ale yeast, which contributes more fruity and spicy aromas to the finished beer?
ale yeast
What is Brettanomyces?
Another type of yeast that some brewers may use for added complexity in the beer style.
What aromas can be expected from a beer brewed with Brettanomyces?
Complex aromas, including:
- Ripe pineapple
- Ripe peach
- Farmyard
- Leather
- Hay
- Earth aromas
What type of bacteria may be used to produce some beers?
lactic acid bacteria
This produces acidity (sourness) in beer, and also used in the production of yogurt and kimchi.
Which yeast strains are preferred by the majority of brewers: ambient or cultured?
cultured yeast
Because it is more consistent and reliable for production needs.
