July 17, 2015 by fhsteinbart
When the uproar about WLP 644 began last December, there was much debate about whether it was a true Brettanomyces culture or not. Omega yeast labs determined that the Genotype was that of Saccharomyces cerevisiae. While it’s still gave the advertised flavor and aroma profile only blends number two and number three were true Brettanomyces cultures. What this really boils down to is whether are not the brewer obtains the desired flavor and aroma components as found in their beer. In this context I believe that more depth of complexity can be obtained by careful blending of different yeast species. While most home brewers are accustomed to brewing with singles strains of yeast, certain flavor and aromatic components can be accentuated by using careful inoculations of wild yeast and/or bacteria. This is where Brettanomyces comes in as another tool in the repertoire of beer brewers. These cultures can also produce large amounts of ethyl lactate and ethyl acetate along with some acetic acid. These cultures can remain active for as long as 16 months on average. So if you want to really get a sour beer without the presence of Brettanomyces you can always add up to 10% acidulated malt to the grist and perform a lactic acid rest (105°F~113°F) and then use a no boil method to producer sour beer. If you wish to halt further souring activity you can alternatively pasteurize the wort first then inoculate with your single or multi-strain yeast.