Nicholas R. Mader. International Centre for Brewing and Distilling (ICBD), Heriot-Watt University, Edinburgh, Scotland; and Fremont Brewing Company, Seattle, WA, U.S.A.
As more breweries continue to develop wild yeast and barrel-aging programs, the
risk for cross-contamination increases substantially. An informational survey
administered to breweries that produce both conventional (Saccharomyces
cerevisiae or S. pastorianus) and wild beers (Brettanomyces spp. or mixed
culture) dissected common methods used to prevent cross-contamination. Feedback
from 16 breweries of various production sizes addressed each brewery’s standard
operating procedures to evaluate similarities and differences carried out in the
following aspects: yeast propagation/handling/pitching, cellaring, filtration,
carbonation, packaging, and quality assurance/quality control. From this
information a baseline for preventing cross-contamination with an adherence to
quality is established for breweries of all sizes. Further, brewery-focused
chemical and hygiene suppliers provided insight toward sanitation and
sterilization procedures, as well as eliminating beer spoilage (or enhancement)
microorganisms such as Brettanomyces. Emerging technologies that improve quality
assurance are also discussed in more depth.