By Chris Jennings
For the Oregon Beer Growler
The process of fermentation is a wondrous one. As brewers, we only have so much control over the outcome of a batch. Much of the work is done by yeast, and we simply strive to create an environment for that yeast to flourish. Besides adding a bunch of sugar for the yeast to metabolize, there is another ingredient that’s often overlooked on the homebrew level: oxygen. Yes, oxygen is bad in a finished beer, giving it a cardboard-like flavor. However, it’s crucial for the beginning of fermentation. Having the right amount of oxygen dissolved in your wort is going to noticeably affect the completed brew. The yeast will reproduce better, fermentation will be faster and the finished beer will be cleaner.
Now that you know that oxygen is beneficial, how do you get it into solution? The easiest and least invasive way to get oxygen into the wort is to either shake your fermenting vessel (not recommended with glass carboys) or by allowing the wort to splash as it flows into the fermenter. These methods are easy and cheap and it’s also next to impossible to get too much oxygen into the fermenter.
Another method involves an oxygen tank (available at some hardware stores) and a diffusion stone (available at most homebrew supply shops). The stone should be connected to a hose that comes off of the regulator on the oxygen tank. When the tank is opened, the tiny holes in the stone force oxygen into the batch. With a pure gas supply, there is the risk of over-oxygenating. If this happens, fermentation will be rapid but the yeast can stall and fail to clean up off flavors such as diacetyl and acetaldehyde — presenting the unwanted essence of buttery popcorn or green apple.
The amount of dissolved oxygen needed is approximately 1 part per million (ppm) for every degree plato. For instance, if you have a beer with a starting gravity of 1.065, your plato is 15.9, so you would need just under 16 ppm of oxygen. There are a handful of ways to measure dissolved oxygen in a solution. The most expensive method is a handheld electronic meter, which comes with a probe that’s inserted into the wort in order to extract oxygen and provide a reading. Unfortunately, this also removes oxygen from the batch, so if you try to obtain another reading from the same spot, the number will be lower.
Another, less-expensive option for measuring is a colorimetric test. This can be found at most aquarium supply stores and works like a chlorine test for a swimming pool. Simply add some wort to a vial, dilute it with water and then add a chemical that will turn the solution a different color (usually blue). Compare this shade to the provided chart and you’ll have a measurement. Of course, this won’t work well on dark beers.
The least-expensive way to measure is simply to experiment, which is what homebrewing is all about anyway! Start by adding small amounts of oxygen with each batch until you notice an improvement in your beer. Record the length of time you allowed the oxygen to bubble or how long you shook your fermenter and then make that a common practice. Once you’re in the right range, you’ll only need to take readings every couple of batches to ensure you’re still on track.
Nasal Blaster [AG]
Nasal Blaster [Extract]
By Andi Prewitt
Of the Oregon Beer Growler
Not every homebrewer has a mass spectrometer to play around with. Or a gas chromatograph, which together can detect and identify chemicals in beer. Of course, not every homebrewer has access to the pros, advising them about quality control and assurance. That makes Adam Fleck the envy of every stove-top and back-deck-burner beer maker in Oregon because he has all three.
While a sensory panel for many a homebrewer consists of a “panel” of buddies heaping on praise while looking to score free beer, Fleck has the equipment and training to conduct sophisticated analysis of his own creations. He’s taken that methodical approach on the road to assist small and midsize breweries with the science aspect of the business. And while there are plenty of companies that provide data on everything from IBUs to DMS, what sets Willamette Valley Mobile Testing apart is Fleck’s ability to bring the lab to a brewer’s doorstep. There may be a growing number of portable canning and bottling services in the craft industry, but the notion of the traveling chemist is still new. A natural reaction to Fleck’s innovative approach might be, “That’s cool!” To which Fleck would respond: “Well, it’s either that or it’s really stupid because no one else wanted to do it because they weren’t crazy enough.”
While it certainly took some bravery to launch a business for which there was no model, the risk appears to be paying off. Fleck has a growing number of breweries from Eugene to Seattle he’s contracted with, including Ancestry Brewing, Black Raven Brewing Company, Culmination/Ruse Brewing and Diamond Knot Craft Brewery, to name a few. He offers multiple services, such as sterility and cleanliness checks, yeast viability assessment and cell count along with tests for everything from water chemistry to pH and hop aromas to off flavors. Shaun Kalis, founder of Ruse and brewer at Culmination, which share the same space, said Fleck conducted dissolved oxygen analysis for that facility to help ensure there wouldn’t be any oxygen pickup in the lines. Following that experience, he believes Fleck’s expertise can benefit brewers who don’t have a Breakside or Widmer budget to invest in expensive equipment.
“Having people like Adam who can do testing and can provide the benchmarks to your company’s standard operating procedures, I think, is a great thing for the brewing community — to make us better and consistent,” Kalis said.
Fleck’s arsenal of instruments is tucked away in what resembles a shiny, black toy hauler. Industrial straps and bungee cords secure his tools as he drives from site to site. One of the most important pieces of equipment looks like a cross between a giant copy machine from the ‘80s and a microwave. That is the gas chromatograph — what Fleck calls his “ace in the hole.” He got experience with it after taking a job in the oil fields of eastern Utah analyzing natural gas and petrochemicals.
“A gas chromatograph to a chemist is like a power drill for a carpenter. It’s kind of a multi-tool, depending on your columns, your injectors, software. [Those] are the bits on that power drill. You can do a lot of things with them. You can do buffing, grinding, sanding, cutting, drilling, screwing, whatever,” Fleck explained. “You’ve just got to change out the end. It’s kind of like a gas chromatograph.”
The technology has been around since the 1950s and is used to separate compounds. Oregon State University’s Environmental Health Sciences Center provides a vivid analogy: Imagine a race at a track meet where the runners begin at the same point — the starting line. However, they’ll finish at different times due to speed. In a gas chromatograph, chemicals are separated by volatility, with more volatile (often smaller) chemicals moving faster than those that are less volatile. The mass spectrometer will then identify the chemicals based on structure.
So, how did Fleck go from using a gas chromatograph in the oil fields to applying the instrument to beer? It all comes back to homebrewing. Turns out, his former boss made beer with a friend and they’d run it through a gas chromatograph to test the alcohol. Fleck decided to explore other uses and discovered the list is huge.
“There’s 2,800 different compounds in beer; 478 affect flavor. And I can get about half of them using my mass spec, so that’s pretty cool.”
When the price of oil plummeted in 2014, Fleck turned his layoff into an opportunity. He relied on the State of Oregon’s Unemployment-Self Employment Assistance, commending the program for providing him with a way to build Willamette Valley Mobile Testing without having to also search for jobs that likely wouldn’t match the wages he made in the oil industry. Another advantage was the unemployment payments that allowed him to pump all initial money made back into the business.
As of June 2016, Oregon had 206 brewing companies and 246 brewing facilities, according to the Oregon Brewers Guild. Those numbers will grow given the amount of applications the Oregon Liquor Control Commission receives for new producers. Plenty of them could use Fleck’s help. Breweries lack quality programs for multiple reasons. Some can’t afford the lab. Others simply don’t have space. And plenty say they don’t need it. But Fleck pointed out that just because brewers believe they’re replicating their processes, doesn’t mean batches will be consistent.
“Their equipment doesn’t always act the same way every time. Their inputs aren’t the same every time,” he explained. “If you don’t measure it, you can’t manage it.”
Fleck contends that “quality and quality control are the next battlefields for craft beer.” They’re factors that increasingly finalize distribution deals, since a quality program provides a better-guaranteed product. The average beer drinker is also more aware of consistency. Fleck said customers are drawn to craft because of the overall experience — part ambience, part novelty and part flavor. Not everyone can identify diacetyl or acetaldehyde, but they won’t hold back if beer quality was “hit or miss” after multiple visits.
“The customer will know when their experience changes. And you’ll hear about it,” Fleck said.
If distributors care and beer drinkers care, the next hurdle is getting more brewers to commit to investing in quality control/quality assurance. Testing services aren’t a tangible purchase like a gleaming new tank or colorful packaging for distribution. But it is one of the most important parts of the brewing process. Fleck is so dedicated to quality, he refuses to test beer submitted to him “because I don’t know how the sample was collected, when it was collected and what has happened to it on transport.” He goes to the source and then tailors a program to fit each brewer’s needs.
Fleck hopes that his one rig will grow into a fleet in the future. There are also plans to expand into distillates, wine and cannabis, the latter of which desperately needs better testing for potency and pesticides, post-legalization. The Portland State University graduate wants to reach out to students at his alma mater by bringing on interns who are majoring in chemistry. However, would-be lab-techs-in-training with spotless GPAs need not apply.
“I was not an A+ student. I don’t want A+ students. I despised A+ students,” he laughed. “I want a student that’s good, but lazy enough to find a better way to do it.”
In the meantime, Fleck will continue to build his client base by meeting new brewers and starting a discussion about quality control.
“The idea of the craft industry is kind of centered around quality. So, yeah. It’s a good product. Why wouldn’t you do it with consistency? You can’t just make great beer once.” Fleck said. “You have to make great beer every time.”
Willamette Valley Mobile Testing
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