Going Pro – Troubleshooting

Going Pro – Troubleshooting

Running into problems in the brewery is standard operating procedure. From burnt PIDs to leaky gaskets, adapting to challenges is what makes a brewer professional. Of course, preventative maintenance, training, and good equipment are essential, but what tools can an individual bring to the partnership? Read below for more about troubleshooting problems in the brewery. 

In the post corona world, logistics have seen many hurdles. From gas prices jumping, to container ships backlogging, every aspect of business is straining. Malt suppliers are facing delays, not only in receiving goods, but in getting them redistributed to breweries. Hop producers face usual challenges of seasonality, but recently wild fires have added an additional layer of complexity. Aluminum cans have been more difficult to obtain by import, and an increase in demand has increased the price over the last two years. What can a brewer do when running into logistics problems? 

Be prepared to act quick. Keep a list of preferred vendors around the brewery but include a set of alternative vendors for each item. In the event a label printer is backlogged beyond acceptability, a transition to a less appealing choice may be required for survival. Do not let perfect be the enemy of success. Occasionally working with less-than-ideal circumstances will be required. 

When other vendors are not a viable option, consider your fellow colleagues. As an industry of “friendly competition”, most local breweries are willing to extend a helping hand. The key is to make associations with peers before the time of need arises, and always be willing to reciprocate. Borrowing a sleeve of 202 LOE ends, or a bag of dextrose for that spontaneous Double IPA, can be the difference between making the release date and sitting alone.

A multimeter is an essential brewery tool. With a quick poke it can identify power issues in electrical systems by examining voltage, current, and resistance. Modern breweries increasingly make use of integrated programming controllers and automated actuators, which means more complex circuitry. When identifying electrical issues, it is a good idea to work through the circuitry starting from the main power source. Set the meter to the appropriate voltage settings, DC or AC, and then probe according to the instructions supplied with the meter. Note the value on the meter and reference a known good source for comparison. This could a book, the internet, or another functioning piece of equipment. More advanced users will be able to check circuits for current, resistance, or continuity to determine more intricate problems. 

Burnt PID relays or solenoid coils are a common occurrence. Often these do not even need the use of a multimeter to diagnose, simply a failure of operation is indicative enough. If other working units exist in the brewery, even ones currently in use, make a field replacement to confirm the failure. Then a new part can be ordered for replacement. Order two, since they can fail without warning. Most solenoid valves will allow for a quick and easy replacement of the electric signal coil, it is often a single bolt. Within minutes you can have a band-aid solution to get you through a batch. Need a few parts? Check out Automation Direct

Be sure to have replacement parts available for the highest wear items and keep a good stock of basic tools. Pump seal kits can be a real pain, but they don’t need to shut down operations. Take time during down shifts to familiarize yourself with the equipment. Understanding the fundamental operations can help when deciding alternative solutions. 

PRODUCT

Product can have a number of issues to troubleshoot, but they typically fall into three basic categories. Flavor is perhaps the most important aspect, as this is what separates craft beverages from low-quality mass-produced options. If flavors do not meet expectations and standards, troubleshooting is required. When possible, create a panel of “qualified” tasters who can help identify flaws. Give each panel member two samples of one batch, and one sample of another, to see if the majority can, in fact, identify a difference. Note the opinions and correlate with previous panel notes when possible. 

Some flavors are both blessing and curse, depending on the product. For instance, Iso-amyl acetate creates a lovely banana character in a German Hefeweizen, but that same ester formation can be a strong flaw in other styles. Low pitch rates, stressed yeast, fermentation temperatures or aeration levels can heavily influence the formation, so take notes!  

The first step in troubleshooting flavor is to identify the offensive culprit. Spicy phenols and fruity esters can be from yeast manipulation, but buttery slickness or acetic vinegar may be an indicator of something much worse. Rouge microorganisms can wreak havoc on the flavor profile of any brew, so keep tight procedure logs. In the event of a problem, they can be analyzed for causation. 

Often flavor discrepancies are attributable to a second category, activity or fermentation. When chemical or biological reactions are used to make a product, there is a high chance for variability. Controlling the environmental factors are key to repeatability, but sometimes unknown issues arise. 

Within 24 hours of casting wort to the fermenter, a brewer should expect to see signs of activity. Most obvious is a bubbling bucket, but do not panic if this is not the case. A drop in specific gravity or in pH can indicate early activity by the yeast. Most yeast will reach exponential log phase in 5-15 hours from pitching, but many factors effect this. In the event no activity is present after 24 hours, consider taking actionable measures. 

Slow, sluggish or stalled ferments are almost always due to yeast/microorganism problems. Although the alcoholic fermentation we require is anaerobic, yeast need oxygen for budding cells. If “young” cells are not created early in the brew, the remaining cells will likely “tire” or stress out and stall early. Feeding micro nutrients is a great way to keep yeast healthy over successive generations, but this does not replace the need for dissolved oxygen. 

A good microscope will aid in fermentation diagnosis. Taking a sample of liquid wort, it can be pipetted onto a hemocytometer for further investigation. Methylene blue stain offers a way to visualize the health of yeast, as well as take a volumetric count for extrapolative purposes. Viability should be in the 85%+ range, and average cell densities should be around 10-15 million cells per milliliter per degree Plato, at the peak logarithmic growth phase, in most cases. If cell counts are close to pitching volume, this indicates a potential issue with the inoculation.    

Other areas of concern might include ABV variance. A difference in the stated alcohol content is usually allowable, but only up to a point. In the event a discrepancy is found, purse the cause until it is corrected. To have product tested by an independent laboratory, try BDAS Testing.

There are cases in which the inoculant will fulfill fermentation, yet specific gravity measurements do not show the expected result. This can be for a number of different reasons. Numbers below the expected final value can indicate hyper-attenuation, or possibly dilution. Gravity readings that are above projections show an abundance of sugar dissolved in the wort. When it does not involve microorganism health, causation can stem from high mash temperatures, short rest times, or poor enzymatic action. 

Missing pre-boil gravity points to extraction inefficiencies. Excessive amounts of “gummy” sediment can form in the mashing and lautering process, and if it fully coats the surface of the lauter bed it can prevent proper sparge rinsing. Over mixing in these situations can also lead to a compaction of the lauter bed, preventing permeation of sparge water through the grain. Basically, it locks up the porous nature of the filter cake. Perhaps the worst outcome is a complete “blinding” of the lauter screens, in which small particulate blocks the openings in the false bottom of the lauter tun. This results in a no-flow situation, and can require the most drastic of actions. 

Troubleshooting requires one tool and it is non-negotiable. An applied mind will enable any brewer to develop an acceptable outcome. More importantly, it will prevent future problems from developing. Giving full attention to each issue that presents itself will build the knowledge and self-confidence required to become a master. When all else fails, reach out to the local brewery colleagues. They may have been down this road before!

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