Nitrogen: The secret superpower of the best breweries
November 18, 2021
Beer is better with nitrogen. From preserving the valuable raw ingredient to purging tanks and bottling the final product, nitrogen has been helping out beer longer than we think. But first things first, why does beer need protection? It’s the usual suspect: oxygen, great for respiration, but an enemy of preservation. Oxygen creates the ideal environment for bacteria and enzymes to wreak havoc on the quality of beer.
Before the days of nitrogen generators, we let nature take its course. Thankfully, carbon dioxide (CO2)—a natural by-product of the fermentation process—also serves as a protective, blanketing gas that prevents oxidation. However, beer fermentation doesn’t release nearly as much CO2 as is necessary for this and today most brewers purchase CO2 for this purpose. Given that CO2 is an expensive gas and that nitrogen can outperform in the above role while being cheaper to produce given its low density, it’s no surprise that brewers are beginning to switch to nitrogen.
Superior results at every stage
There’s another reason why nitrogen edges out carbon dioxide: It does a better job of preserving flavours and enhancing taste. It does not interfere with the beer and so, allows the intended flavour to shine through. Poured with the right tap, the foam created by nitrogen is much thicker and more persistent than that created by carbon dioxide, due to the size and behaviour of the nitrogen in the bubbles. All this, of course, might be a matter of preference, but what can’t be debated are the many advantages nitrogen brings to the brew process. Combined with the oil-free air compressors already in place at breweries, nitrogen generators help with the following:
Clearing out tanks between batches
Pressure transfer of beer between tanks
Pushing beer through filtration
Pushing beer to drain counter pressure on bottling machine filler
Storage tank pressurisation with nitrogen
Blanketing bulk storage
Kegging and bottling
If this weren’t enough, the nitrogen generated, in combination with compressed air, can be used for pneumatic valve operations and to keep beverage lines clean and dry. It is also a better option for bottle-drying compared to regular air sources. It must be noted that the nitrogen used across the stages mentioned here must be food-grade and must comply with the regulations and minimum specifications (EIGA/JECFA, Directive 89/107/EEC; FDA Article 21). Pneumatech’s nitrogen generators allow you to set the highest standards of purity for use at your brewery.
Advantages of onsite nitrogen generation
Improves shelf life: Not only does a nitrogen atmosphere limit the shelf life of the valuable raw ingredient (hops) in storage, the use of nitrogen across the brewing process extends the shelf life of the final product.
Lowers cost: Capital investment in onsite nitrogen generators are recovered quickly, given that nitrogen is cheaper to generate compared to traditional third-party gas supply, which also requires several hours of order co-ordination and runs up carbon costs through transportation.
Safety: While high-pressure cylinders present a safety risk and must be subject to rigorous protocols, onsite nitrogen generators are far safer and subject to the same protocol as air compressors.
Saves time: Co-ordinating supply and deliveries of nitrogen supply takes time. Onsite nitrogen generation ensures nitrogen availability on demand.
Limits wastage: When using third-party nitrogen tanks, unused nitrogen is usually ‘blown off’ to prevent the risk of explosions. This results in gas wastage. With onsite gas generation, nitrogen is produced only as required.
When air compressors are used in a brewery for bottling, kegwashing, etc., the compression of ambient air pulls in all the humidity and particulates that are floating around in the air. That concentration of liquid and contaminates will get down stream of the compressor and cause many issues for a brewery of any size.