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  • Solving Problems and D.O. Issue is Laid to Rest

    Weve faced a lot of challenges as a young businessmany of our own making with inexperience and ignorance mostly to blame. We are far from perfect, but one thing I can say about our organization today is that we have developed our own set of core values, and more importantly, we have learned to follow those values to help us weather storms quickly. One of our core values is transparency. So, in the spirit of extreme transparency I would like to share some details of a recent quality control issue we had with dissolved oxygen in our packaged beer. If your eyes are glazing over you might want to stop here, and Ill spare you the details. To sum it all up, we have new equipment and ever-improving procedures in place to ensure only quality product is leaving our brewery.

    The first indication of a problem was from a longtime customer, who told us that although she loved the brewery, she would no longer be buying our beer. She claimed to be detecting a lot of diacetyl in a some of her favorite brands and it was off-putting. This customer seemed to know a thing or two about beer, so we didnt ignore it. But our initial reaction was, admittedly, one of denial. We took out several QA samples and did taste testing. We ran samples through our protocol for package air testing and forced diacetyl tests. No one at the brewery had detected any issues and we hadnt received any other feedback from the market to suggest this was a problem. So, we wrote it off and decided as a team that it was nothing of concern. After all, we had processes and procedure that would prevent and identify any issues early. We wrote her an email explaining our quality control regimen and that we werent able to detect the problem. Basically, we said sorry youre detecting this, but we aren’t seeing anything, so it must be something else youre picking up.

    Problem solved. High five. We’re awesome… Nope.

    Every batch gets several cans held back for sensory testing. We hold these cans in different conditions to simulate how our product might be treated in the market. Some cold, some hot, some in flux between hot and cold. Then we have a sensory panel and try to pick up off flavors or any changes in the product over time. This is done for quality assurance and to maintain an accurate best buy date for our product in the market. During one batch testing about a week after we decided nothing was wrong, we cracked open a can and there it wasa whiff of diacetyl. Some people are very sensitive to the smell, which is identical to butterscotch. I have done countless off flavor tasting—both at brewing school (Siebel Institute) and at the brewery on a regular basis. I know that I am not particularly sensitive to diacetyl. So, when I poured the beer out into a glass with Ben, our head brewer, and I got a butterscotch bomb, we knew there had to be an issue. Because of regular batch testing, we knew there were no beer spoilers present like pediococcus that can sometimes be mistaken for diacetyl. And we were already doing regular forced diacetyl tests after cold crash and package, and nothing was showing up. We opened more cans than usual to see if we could find the problem again. A few hundred cans later we noticed a pattern, which was that there was not much of a pattern at allbut a problem was clearly there. It was particularly present in the hazy New England style IPAs we had been doing as of late. Random cans were showing up with a buttery taste and dark color. These NE IPAs, because there is more residual yeast and protein left in the beer, tend to be particularly susceptible to D.O. pickup. We were already testing our package air and not picking up any problems, but everything was leading to oxygen pickup during packaging. And it seemed like the problem wasn’t isolated, but actually getting worse. We started to get feedback from our customers noticing the same thing. So we turned to technology. We had Anton Paar demo a D.O. meter and we knew we needed it. We could measure D.O. accurately and instantly at every point of our process, including packaging. It was completely unaffordable to us, but we decided that we had to have it as part of our regular testing, because otherwise we would be flying blind. The meter wouldn’t solve our problem, but if we could identify it, we would be able to know immediately if the problem returned.

    Sometimes, we focus on the wrong things. The problem right in front of our face is often not the real problem--it's a symptom. In this case, D.O. was just a symptom of inadequate standard operating procedures in our packaging process. For a company that prides itself on quality and rigorous protocol this is a hard pill to swallow. But once we did, we worked tirelessly to improve everything about the way we operate. At first, we held out hope that the issue would be one simple problem… a leaky valve, a gasket, co2 purity, etc. Once we replaced every part we thought could be causing the issue, the problem persisted. The reality was much different. We had nothing in place to ensure that things were being done the right way. And we didnt even know what the right way was anymore. It had been five years since any of us were trained on our canning line. We had a belief that we were doing it the right way, but the evidence was proving otherwise. So, we had Wild Goose, our canning manufacturer, send someone down to look at the problems and retrain our staff. The company is tremendous. They replaced the flow sensors on our five-year old machine free of charge, because they started using a better version. They worked with us for two days to make sure the problem was solved. Heres a complete list of every change we made and equipment we purchased over the course of six weeks:

    New canning line flow meters

    New fill valves

    New fill-head gaskets

    Software update

    Reworked fill manifold, fill tube placement

    Replaced CO2 lines to canning line and bright tank

    Changed pre-rinse timing

    Changes co2 purge timing

    Increased testing protocol

    Included regular DO testing throughout the run.

    Changed date coder to indicate can#

    Changed cellar protocol to minimize turbidity during transfer

    Slowed speed of canning conveyor

    Adjusted temperature of beer entering canner. 

    Rewrote Standard operating procedures for canning startup and shutdown.


    At the end of the day it was not one problem but a host of problems, all stemming from the fact that we stopped trying to learn and improvewe had become complacent. Now we have data to back up everything we do. We have operating procedures that ensure were putting out great product and we can identify problems quickly when they occur. The best part of it all is that this has inspired everyone in our company to look at all aspects of our production to see what we can improve, and Im excited to see what we can accomplish now with this new mindset.

    Quinby Chunn, owner, and the team at Southern Prohibition Brewing Co.

    Thank you for your continued business, and we hope you can join us February 3rd for our Space to Face IPA can release at the brewery. This beer is phenomenal, and we are excited to put it in quality cans for you to take home.