Anyone familiar with the art of making sourdough bread knows about sourdough starters and the care required to bring one back to life after periods of dormancy. Sensory panels are no different, in that they require some love after periods of reduced production. As many organizations look towards ramping up production again, here are couple of factors to consider.

Keeping You and Your Panel Safe

As panel leader, you can come into contact with many people every day, so make sure to take care of yourself while being mindful of other’s safety.

• Follow official guidelines, wear applicable PPE, and maintain a safe physical distance.
• Maintain rigorous cleaning regimens by wiping down surfaces and increasing glassware wash temperature and frequency.
• Consider scheduling your panelists to participate at staggered times to limit the amount of people in a single space.
• Minimize the use of shared surfaces by propping doors open and requiring panelists to perform their evaluations using personal devices.
• Use scent-free cleaners to disinfect your space. If this is not possible, use fragrant cleaners at the end of the day and less-potent alcohol wipes during panel.

Panelist Calibration

Give your panel a kickstart by running a quick ‘welcome back’ training. Revisit your brand profiles, discuss any at-risk raw materials (see water and C02 below if applicable), and review potential off-flavors.

In panel, focus on what matters most. While panelists are dealing with their own new realities, attention spans will be limited, so choose samples carefully and focus on getting product released.

Water Quality (If Applicable)

When fully operational, water is constantly being flushed through production systems, but after weeks of inactivity, water can remain in holding vessels, pipes and tanks. This stagnant water provides a perfect environment for mold to develop, so the first order of operation is to flush the system and CIP tanks. Luckily, the stagnant water in holding vessels can be used to CIP, so no water should be wasted in this process. Once sparkly clean and water vessels are replenished, taste water from different areas to make sure it’s free of earthy, musty and metallic flavors.

Tip: Get into the routine of tasting water every day. Run TTT tests for water on your panel and before mashing in to flag potential problems with filtering systems, heating systems, city water supplies and holding vessels.

CO2 Quality (If Applicable)

One of the many unforeseen problems we are currently facing is a carbon dioxide shortage. This means you may need to change suppliers and quality could be variable. An easy method of evaluating CO2 quality:

• Bubble CO2 from the system through distilled water in an inert bottle (make sure not to pressurize the bottle).
• Allow the CO2 to bubble thorough the water for at least 5, and up to 15 minutes.
• After bubbling, seal the bottle and taste with your panel.

Common CO2 defects include mercaptans, acetaldehyde and various phenolics and sulfurs.

Yeast Health (If Applicable)

Just like an unfed sourdough starter, yeast slurries are sluggish and can produce off flavors if not treated properly. After long periods of down time, it is ideal to start fresh with new props or new lots from your supplier. If you cold stored yeast while away, you may be able to use it after measuring viability and yeast count.

Brooke Bell of Goose Island recommends using no lower than 90% viable yeast and to ideally make a one-off as flavor derivations should be expected in the first batch.

“Consider rocking out a simple Pale Ale with low ABV and BU’s to use as a fresh harvest source.” She adds, “If you’re going to dry hop, do it after the yeast is harvested.”

Fermentation off flavors result from stressed yeast (sulfidic, acetaldehyde), yeast death, or early flocculation (autolysis, diacetyl). Tasting in the middle of fermentation is unreliable, so an easy way to catch poor yeast health in fermentation is to monitor pH and arrest fermentation once the pH begins to rise, indicating autolysis.

Once the fermentation is complete and the product stabilized, taste for defects in maturation while adjustments can be made. Finally, taste the batch again once before packaging to verify trueness to target and absence of undesirable flavors.

Long-Term Benefits

Although the coming weeks and months may require some special care and attention, it is also a unique opportunity to embrace change and adopt new best practices that will benefit your program far into the future. We wish you a safe and productive return!

DraughtLab offers practical and approachable Sensory Analysis Solutions that deliver real-world value to food and beverage companies. Visit our website or reach out to us at info@draughtlab.com to learn more!