Is 71B a killer yeast?

Answered by Vince Keith

71B , also known as Lalvin 71B-1122, is indeed considered a killer factor sensitive strain. This means that it is more susceptible to the presence of killer factors produced by other yeast strains. Killer factors are proteins that some yeasts produce to inhibit or kill other yeast strains in their environment.

The term “killer yeast” refers to strains that produce these killer factors, while “sensitive yeast” refers to strains that are susceptible to being inhibited or killed by these factors. In the case of 71B yeast, it falls into the sensitive category.

The presence of killer factors can have significant implications for the fermentation process and the establishment of a dominant yeast strain. When a killer yeast strain encounters a sensitive strain like 71B, it can inhibit or even kill off the sensitive strain, preventing it from becoming the dominant strain in the fermentation.

As a sommelier and brewer, I have come across situations where the choice of yeast strain can greatly impact the outcome of a fermentation. It is essential to consider the characteristics and sensitivities of different yeast strains to ensure a successful fermentation.

In the case of 71B yeast, its sensitivity to killer factors means that it may face more challenges in establishing itself as the dominant strain in a fermentation. If other yeast strains present in the environment produce killer factors, they can potentially inhibit or suppress the growth and activity of the 71B yeast.

However, it is essential to note that the impact of killer factors can vary depending on the specific strains involved and the conditions of the fermentation. Factors such as temperature, nutrient availability, and the timing of yeast inoculation can influence the interactions between different yeast strains.

To mitigate the potential challenges posed by killer factors, some brewers and winemakers may choose to use specific techniques or strategies. For example, staggered yeast additions can be employed to allow the 71B yeast to establish itself before introducing other yeast strains that may produce killer factors.

71B yeast is considered a killer factor sensitive strain. Its ability to establish itself as the dominant strain in a fermentation may be affected by the presence of killer factors produced by other yeast strains. Understanding the dynamics of killer factors and employing appropriate fermentation techniques can help overcome potential challenges and achieve desired fermentation outcomes.