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Visitors to our brewery in Chico, California, often comment about the rows of cylindrical columns affixed to the top of the building. There they stand, rows of fermenters in rank and file, like silvery pillars in an acropolis of steel.
Fermenters are possibly the most important feature of a brewery. Inside these tanks is where billions of yeast cells transform sugary wort into beer—literally, the place where beer is born.
Proper fermentation is key to quality beer. If something goes wrong there, every other variable in the alchemy of brewing is for nothing. We dedicate a lot of time and effort to monitoring our fermentations and watching as the yeast does its work.
When the brewery was in its infancy, we used repurposed stainless steel dairy tanks with open tops as our fermenters. These open tanks are well suited to the unique brand of American ales we developed at Sierra Nevada. As the brewery grew we added larger, closed tanks that are easier to clean and have more sophisticated temperature controls, allowing us to make a wider variety of beers including lagers, which require longer storage at cold temperatures.
We know just how important these tanks are, and when it came time to purchase the fermenters for our new brewery, quality was paramount. Each tank was fabricated to our exact specifications. Ken and Brian Grossman flew to the manufacturer in Germany to inspect them individually as they were being built.
After their arrival on site, getting these massive tanks upright and into their footings proved a challenge all its own. The tanks sit in a poured concrete structure with openings in the ceiling to accommodate the conical bottoms of the fermenters. The tanks—some up to 60 feet tall—were lifted by massive cranes and placed securely in their moorings. We installed walkways atop the tanks for cleaning and maintenance and, like our Chico facility, we intend to install valves designed for the release and capture of CO2 from fermentation, which we recycle back into the brewery for things like tank pressurization and bottle filling.
Altogether, we installed 28 tanks, which can accommodate a whopping 793,000 gallons of beer. This additional capacity will bolster our total production and take some strain off of our brewery in Chico. While much smaller in scale, our North Carolina brewery will be an important key to our production.
These fermenters—collectively known as the cellar—mark an important step in the commissioning of our new brewery. As the months progress, we’ll complete a labyrinth of piping and bring our brewhouse online and, soon enough, these tanks will be filled with the inaugural wort. The yeast will carry on and do its work, just as it has in Chico for 33 years.