Yeast is the life force for making beer. Although this ingredient is by far the most mysterious to home brewers it is has so much influence on the flavor that some breweries maintain their own strains and keep them on lock down...top secret. These microorganisms are hungry, and they love sugar. The bi-product of this appetite is simple: alcohol, co2, and energy (heat).
Before the power of yeast was truly realized, the fermentation and production of alcohol seemed to be magical occurrence. Aging wort left open to the elements would gather natural yeasts from the air and atmosphere. These yeast had the same common objective as the strains used today, to eat. However the old world approach obviously has its disadvantages. Everything else in the air, including oxygen, bacteria, and other organisms also found its way into the wort. This reduced the predictability of the flavor.
Yeast for brewing comes in two major classifications for brewing; top fermenting and bottom fermenting. They are names as such due to the where they settle during the fermentation process. Although the definition of an ale and lager is not based on the yeast, these types of beer do generally use the varying types. Lagers are generally brewed with bottom fermentting yeast. And this is due to their vitality at different temperatures (lagers ferment at cooler temperatures).
Yeast is very often recycled and reused after brewing. For the homebrewer the technique is simple and can be accomplished by saving some beer from the bottom of the fermentation tank. For the breweries its similar, however the equipment is generally designed for easy extraction. The reuse varies on the quality of the preservation and extraction process. For homebrewers this can be from 4-6 times. The professional brewery can go as high as 10-12. After this the risk of ruining a batch by not having enough active yeast starts to become too great.
- Attenuation: 73-80%
- Famous for its clean flavors, balance and ability to be used in almost any style ale
- Accentuates the hop flavors and is extremely versatile
- This yeast is famous for its clean flavors, balance and ability to be used in almost any style ale. It accentuates the hop flavors and is extremely versatile.
- This lactic acid bacteria produces moderate levels of acidity and sour flavors found in lambics, Berliner Weiss, sour brown ale and gueze.
- Attenuation: 75-82%
- Flocculation: Low
- Optimum Ferment Temp: 70-75°F
- Alcohol Tolerance: Medim-High
- White Labs WLP677 Lactobacillus Delbrueckii Yeast Bacteria
White Labs is one of the industry leaders in commercial yeast propagation. Now you can use exactly the same yeast and bacteria strains used by hundreds of popular commercial craft breweries at home on your own beers. White Labs liquid yeasts can be pitched directly into 5 gallon worts up to 1.055 or used in a yeast starter for larger batches or stronger beers.
Strain Specifics: WLP677 Lactobacillus Delbrueckii
This lactic acid bacteria produces moderate levels of acidity and sour flavors found in lambics, Berliner Weiss, sour brown ale and gueze.
- Attenuation: > 80%
- Flocculation: Medium
- Optimum Ferment Temp.: 68-75°F (20-24°C)
- Alcohol Tolerance: Medium-High
- Classic cider yeast. Ferments dry, but retains flavor from apples. Sulfur is produced during fermentation, but will disappear in first two weeks of aging. Can also be used for wine and high gravity beers.