If you've ever remarked on the smooth creaminess of a pint of Guinness, you've picked up on the key difference in its carbonation: Nitrogen rather than carbon dioxide. Such 'nitro' beers have become a trend in recent years, with major U.S. breweries and small startups alike offering nitro products. Nitrogen keeps bitterness in check and balances out the hops to make drinkable craft brews, but it also increases the risk for breweries.
How Nitro Beer Works
CO2 is a natural byproduct of the beer brewing process, occurring when the yeast consumes the natural sugars in the wort. Breweries often add additional CO2 when kegging or bottling the beer. The carbon dioxide gas adds flavor, aroma, and those bubbles that fizz against your tongue. CO2 is also slightly acidic, so it can intensify the bitter flavors in a brew. While this might be desirable in a hop-bomb IPA or citrusy hefeweizen, it isn't always complementary to the flavor of the brew.
Nitrogen gas adds carbonation without the bitterness, allowing the beer's natural flavors to remain. It delivers a new drinking experience with favorite brews. Nitrogen is harder to dissolve than carbon dioxide, so the resulting bubbles of carbonation are smaller.
The mouth feel of a nitro beer is smoother or creamier. Dark beers -- stouts and porters -- pair well with nitrogen gas, but the nitro technique can also present a new take on a classic IPA or wheat ale.
While the process of adding nitrogen to beer is similar to carbon dioxide, breweries must take some extra precautions. Nitro beers must be stored in tanks rated to a higher psi, 25 rather than 15. Breweries must also take precautions to ensure that nitrogen isn't leaking out of the supply lines or canisters and onto the brewery floor. Nitrogen gas displaces oxygen from the air, so if it did leak, the room would soon become oxygen deficient. Breathing oxygen deficient air causes confusion, dizziness, respiratory distress, and death via asphyxiation. Since nitrogen gas has no color or odor, breweries need a tool to check for leaks by measuring ambient oxygen levels.
How an Oxygen Monitor Protects Brewery Staff
Since staff cannot tell if there is a leak -- there's nothing to see or smell -- there is no way they can protect their health if a leak occurs. Oxygen monitors provide a safeguard against respiratory distress by measuring oxygen levels. As long as there is no leak, the oxygen in the brewery should remain constant. If nitrogen gas starts to leak, oxygen levels will fall. Before oxygen levels fall to a critical threshold, an oxygen monitor will sound an alarm. There's also a flashing light to get the attention of staff.
When the alarm goes off, workers can exit the brewery floor before the lack of oxygen poses a threat to their health. Emergency personnel can then come and contain the leak.
PureAire offers a robust oxygen monitor with two alarm levels: 19.5 percent and 18 percent, a 90 db alarm, and a bright flashing light. The oxygen deficiency monitor is designed to mount on the wall and features an easy-to-read digital interface, so workers can tell at a glance whether there's a problem.
PureAire's monitors use zirconium sensors, which deliver reliable performance even during thunderstorms, sudden barometric shifts, and other weather incidents. These O2 monitors are designed to last for 10 or more years with no maintenance or calibration, unlike other products that need regular maintenance to remain effective.
Breweries should place one oxygen monitor in the area where beer is bottled and kegged and another where nitrogen is stored. This ensures the entire facility is protected from leaks.
Left Hand Brewery, a pioneer of the nitro beer trend, relies on PureAire products for workplace safety. Learn more about the oxygen monitor form PureAire at www.pureairemonitoring.com.