When Good Bugs Go Bad – Contamination Detection in a Mixed Fermentation Brewery
- Posted by ksteblenko
- On June 5, 2017
Fermentation is a science dating back to the first known civilizations on this Earth, and has helped to shape the world as it is today. From bread and beer to sauerkraut and yogurt, fermentation has shaped cultures and traditions across the world. The vast diversity in fermentation is being rediscovered in the beer industry as the craft beer revolution gains momentum and brewers seek out new and exciting ways to brew. Housing these fermentations, however, can easily lead to cross contamination and unintended consequences. Modern breweries must take many steps to both prevent and detect the variety of microbes, both intended and not.
The recent boom in the craft beer industry has allowed many breweries to begin experimenting with a variety of different fermentation techniques. On the East Coast, we’re pioneering a new style of ale, New England IPA, which features an almost opaque level of haziness and an aggressive fresh hop flavor and aroma. Here at Jack’s Abby we employ a traditional German method of brewing, known as “decoction,” in which we heat the mash (grain and water mixture) by boiling small portions of it and reintroducing it to the remainder to slowly raise the temperature and get more enzymatic activation. One of the most exciting new avenues in craft beer, which is actually a very ancient method, is the intentional introduction of wild yeast and souring cultures to produce a tart, funky blend. These beers can be fermented quickly, as a normal ale, or left to sit in barrels or wooden tanks for years to develop a myriad of flavors and sensations.
The largest challenge for any brewery that is beginning to embark on a sour program is the ease at which contamination becomes an issue. The same microbes that are used intentionally to produce a beautiful bouquet of flavors and aromas in a sour beer are the same microbes that can ruin a classic, clean beer when introduced into the yeast strain or the package. Not only can they produce off flavors, but in some instances they are able to produce dangerous amounts of internal pressure in a sealed package or excessive amounts of alcohol, more than what is stated on the label. While changing package formats and maintaining Good Brewing Practices helps to eliminate almost all of the risk associated with these mixed fermentations, detection of the microbes throughout the process still remains as one of the main roles of a Quality Lab.
Balancing adequate testing and affordability is a delicate line to walk as a brewery starts out, and choosing how and when to expand that program can be difficult. At Jack’s Abby, we began with a microscope and a gram stain kit, and we’ve grown to beer spoilage bacteria and yeast specific PCR testing. Changing our detection rates from 5-7 days to 3 hours has a vast impact on our ability to brew beer and maintain our brand identity, while still allowing us to experiment heavily at Springdale by Jack’s Abby. We’re excited to share some of these new batches with you and hope to introduce you to something you’ve never tried before.