Written by James Shellhammer, Quality Control Program Manager
The Importance of Quality Control
Behind great beer lies a great brewer. While that is true, it’s only part of the story. Look deeper into the processes that lead from beer’s four main ingredients—water, malt, hops, and yeast—to that pint in your hand, and you’ll see that without intention and attention at every step—ingredient sourcing, wort production, fermentation regulation, cleaning, sanitizing, packaging, and storage—that the final product can easily miss meeting the brewer’s vision. Quality assurance and quality control programs aim to ensure that every beer produced meets the expectations of both the brewer and the consumer.
When I started at Silver Branch nearly a year ago, the brewery was barely 6 months old. In that 6 months, Christian and Brett had been successful in starting to build the Silver Branch brand, consumer base, and reputation. As these things grew, so did the realization that Silver Branch needed a quality control program to maintain and improve the reputation that they had been working so hard to build.
A Happy Coincidence
Silver Branch needed a scientist, and this scientist needed a brewery. For nearly a decade prior to joining the Silver Branch team, I was a researcher in biomedical science. In my PhD research, I studied yeast metabolism in response to environmental stress conditions. While I was a graduate student, I used my expertise in yeast biochemistry to become an avid home brewer, and my hobby soon turned into my passion. I spent just over 2 years in Dublin, Ireland as a postdoctoral researcher. While living in Europe, I traveled the continent experiencing different beers and beer cultures, learning about beer history, and dreaming of melding my passions for science and brewing into a career. At Silver Branch, I have been able to turn my dream into reality.
When I met Christian and Brett to talk about potential employment, we ended the meeting with a tour of the brewery. Off to the side, next to a stainless steel sink, there was a cluttered, catch-all table full of tools and parts, and some shelves with odds and ends of scavenged lab supplies from breweries past. It was on this table that they measured the gravity of ongoing fermentations. Now, the sink is still there, but the clutter and old table are gone. For almost a year, I have been slowly building a lab space, turning it from a cluttered corner by a sink that could measure gravity and pH into a small, tidy lab space that is now capable of determining yeast cell number and viability for consistent pitch rates, dissolved oxygen in wort and fermenting and packaged beer, efficiency of sanitation, preparing sterile media, and more.
Develop, Test, Refine, Repeat
Once we had the capability to make measurements and conduct tests, the real work could begin. Quality assurance is focused on ensuring quality in the processes used to make products. With ongoing expansion of the brewery and a constant addition of beer styles, there is a constant need to stay on top of best practices for our cleaning and sanitation procedures, microbe handling, and fermentation protocols. We start with a standard operating procedure, or SOP, usually formed from science-based sources such as the Master Brewers’ Association of the Americas and the American Society for Brewing Chemists. As we repeat procedures, and collect more data, we decide whether our SOPs are sufficient, or if we can make any changes to improve our practices. The process is iterative, and we always strive to become better based on what the data are telling us.
Quality in Every Aspect
Since starting the lab and quality program, we now monitor the progress of each beer from raw ingredients to final package. Ensuring consistency starts with ingredient tracking. Using the same lot of hops and malt from batch to batch removes variability from crop year, terroir, and ingredient processing. Consistent water chemistry ensures the proper body and mouthfeel for a given style. At Silver Branch, we use reverse osmosis to strip ions such as calcium, sodium, magnesium, chloride, sulfate, and carbonate from the town water supply and reconstitute the brewing water with the appropriate ion concentrations for the beer style. Perhaps the most important ingredient to keep tabs on is yeast. Yeast is alive and always trying to survive. However, the ideal conditions for yeast to thrive are not the same as the ideal conditions for making beer. Fermentation in the brewery is stressful on yeast in many ways–among which are temperature, pH, pressure, and alcohol concentration–so someone in the brewery (me) has to make sure that an appropriate balance is struck between the conditions for happy yeast and those for delicious beers.
In a brewery, oxygen is a double-edged sword. High levels are critical at the beginning of fermentation to help yeast grow and reproduce. Low levels, as low as possible, are critical in maintaining the shelf life of finished beer by limiting oxidation of alcohol and components from malt and hops. Fortunately, yeast will consume nearly all of the oxygen in wort. Unfortunately, oxygen can be picked while transferring the beer from the fermenter to the bright tank, and also during packaging. We’ve recently purchased high-range and low-range dissolved oxygen meters to make sure we are hitting our marks at each step of the process.
Once the beer is finished and packaged, it is time for quality control, that is, making sure the product meets consumer expectations. In the past few months, we’ve begun to build our sensory analysis panel. We’ve started weekly tastings of packaged beer of each brand that has been stored warm or cold for set amounts of time. We asses each sample for its trueness to brand, any off flavors, and its warm- and cold shelf life. At the end of a tasting session, we discuss any recipe or process modifications to hone in on our vision for particular brands and whether each brand still meets our quality standards.
Onward and Upward: Next Steps in Quality for Silver Branch
In the next few weeks, our new CODI canning line will arrive! This will be a huge upgrade over our current canning line. It will package three times faster and provide the perfect fill in every can. Counterpressure filling will virtually eliminate oxygen pick-up, extending the shelf life of Silver Branch beer. The new kit will also include a date stamper, so be on the lookout for “born on” dates on upcoming releases to know that you’re getting our freshest beer.
In the next couple of months, I hope to expand our capabilities in microbiology. Right now, we’re limited to cell counts and viability testing for yeast. Handling multiple yeast strains always presents a risk of cross-contamination with other brewing strains or wild microbes that are present in the brewery and on our skin and clothes. Fortunately, our cleaning and sanitation SOPs are proving sufficient to avoid such problems, but having the ability to do strain purity testing in-house will certainly bring peace of mind and allow for early detection of any issues.
Finally, we at Silver Branch want you to know that delivering a quality product is foremost in our minds, and we are making every effort to make it so. I am personally very proud to hold the position of Quality Control Program Manager at Silver Branch, and I work hard every day to make sure our beer meets our high standards and yours. Stay tuned for upcoming posts covering individual aspects of our quality program in more detail.
