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.
