Wineries Turn to Nitrogen as the Superhero of Industrial Gases.
By: Cheryl Gray
Nitrogen use in winemaking is a carefully orchestrated and scientific process. Its chief role is to guard against the adverse effects of oxidation, which diminishes both the quality and shelf life of wine. Consider the vinegar-like taste of a wine left opened or unfinished for too long and immediately understand why wineries use nitrogen to prevent oxygen exposure during production and storage.
While multiple inert gases are available to prevent oxygen from coming into contact with wines, experts say that the choice of which industrial gas to use is linked to cost, availability and the type of wines produced. Nitrogen is a popular choice because it is in ready supply, making up roughly 80% of the Earth’s atmosphere. That means it is available at an attractive price versus other industrial gases.
Penelope Gadd-Coster is Executive Director of Winemaking at California’s Rack and Riddle Custom Wine Services. She told The Grapevine Magazine that cost and efficiency are the reasons her winery opts to use nitrogen.
“It is an inert gas, inexpensive…and there are generators for nitrogen, so outside gas companies are not needed,” she said.
Like Gadd-Coster, proponents of nitrogen use in winemaking point to multiple benefits derived from deploying nitrogen gas generators, which allow wineries to produce nitrogen gas on demand. That, in turn, can help boost productivity. The use of a nitrogen gas generator also eliminates the safety risks associated with high-pressure gas cylinders. Additionally, those in-house generators bypass vendor issues that might include price increases, long-term contracts, delivery schedules, surcharges and tank rental fees.
There is also the benefit of low energy use, resulting in more stable long-term costs. The option to expand is attractive, too, since, with nitrogen gas generators, there is room for adding extra capacity to accommodate a winery’s growth.
On Site Gas Systems, Inc.
One of the global leaders in gas generating technology is On Site Gas Systems, Inc., based in Newington, Connecticut. Its President and Founder, Francis X. Hursey, was among the veteran scientists and engineers who developed pressure swing adsorption oxygen technology for NASA’s Project Apollo space program, which sent the first humans to the moon. Hursey has received multiple patents in non-cryogenic gas technology, medical products and nitrogen applications. After developing PSA oxygen technology for the Apollo Breathing Air Team, Hursey would use that same core knowledge to launch On Site Gas Systems in 1987.
Michael Montesi is Sales Manager of Commercial Products for On Site Gas Systems. He told The Grapevine Magazine about the design and features of one of the company’s latest nitrogen generators for on-site use.
“We offer a newer unit called the Nitroblast that is specifically designed for the beverage industry,” he said. “The main innovation of this product is the compact size and all-in-one product integration. That is very cost-effective for the small user that might have been prevented from purchasing a nitrogen generator in the past.”
Montesi said that nitrogen systems manufactured by On Site Gas Systems are based on continuous innovation, which ensures that the company is not only staying ahead of the curve but also defining it. He pointed to a research and development team whose members have decades of experience knowing how to deliver innovation without making it complicated.
“We specialize in systems designed, sized and built for the correct purity, pressure and ﬂow for each application,” said Montesi. “Our philosophy is to keep the simple processes simple and make complex processes less complex. This way of thinking has formed the basis for our product reputation–safe, continuous, flexible systems that provide cost-saving, reliable gas generation.”
Parker Hannifin is another global industry front-runner manufacturing compressed air treatment and gas generation products. The company produces a wide range of membrane module and pressure swing adsorption nitrogen gas generators. It’s been selling nitrogen gas generators to the wine industry for three decades.
Randy Peccia is Product Sales Manager for Parker Hannifin in its Industrial Gas Filtration and Generation Division, based in Lancaster, New York. He explained how both membrane and PSA technologies allow users to generate on-site nitrogen gas with a compressed air source.
“Membrane technology uses bundles of hollow-fiber contained within a tube. The fiber walls selectively separate compressed air by permeating oxygen, water vapor and other waste gases to the atmosphere,” Peccia said. “Nitrogen molecules are retained within the walls of the fibers resulting in the delivery of nitrogen gas of 90-99% purity to the application. Some membranes are capable of achieving 99.5% purity. With no moving parts, membrane modules are a cost-effective, reliable and safe solution to on-site nitrogen gas generation.
“PSA is a regenerative technology that uses columns filled with carbon molecular sieve to separate compressed air,” he said. “In the ‘online’ columns, oxygen and other waste gases are selectively adsorbed by the CMS, allowing nitrogen gas of 95-99.999% to pass through to the application. The CMS in the ‘offline’ columns is regenerated by releasing the pressure in the columns and venting the waste gases to the atmosphere. This constant swing in pressure between columns is why the technology is called pressure swing adsorption.”
Peccia told The Grapevine Magazine that PSA technology is the primary candidate for wineries because of the purity levels it allows users to achieve. He added that depending upon the amount of nitrogen used at a given winery, Parker Hannifin’s PSA nitrogen gas generators can deliver, at minimum, a 12- to 18-month payback with low energy usage and stable gas costs. Peccia detailed the most common uses of nitrogen in wineries: sparging, flushing and blanketing.
“During the fermentation process, oxygen will naturally dissolve into the wine. Sparging is a process where very fine bubbles of nitrogen are passed through the wine to remove dissolved oxygen. It is important to note that red and white wines differ in chemistry, and because of this, the use of nitrogen gas sparging may differ in production. For example, some wines require a certain amount of CO2,” he said. “To avoid removing CO2 below the required level, a mixture of CO2 and nitrogen is utilized for sparging. This is most common in production of white wines but required for some red wines.
“During production, wine is transferred between multiple containers via pumps and hoses before becoming a finished product and sealed into a bottle. This adds the risk of oxygen exposure. Nitrogen is used to flush out oxygen within storage tanks, barrels, transfer pumps, hoses and bottles to prevent unwanted oxidation. Flushing is also used during bottling before a bottle is filled with wine.
“Nitrogen can be used to blanket the ullage, or headspace, of partially filled containers used throughout the production process. Headspace is the result of not filling a container from top to bottom. This space helps to compensate for the expansion and contraction of the wine due to changes in ambient temperature. Headspace is also a factor during bottling where there is a space between the bottle seal and the wine. Blanketing the headspace of a container before a bottle is sealed helps to eliminate oxygen exposure,” said Peccia.
Bars and restaurants use nitrogen gas in wine dispensing, reducing the risk of oxidation in a bottle of wine before that bottle is empty. That means those businesses can stretch the shelf life of a bottle of wine for one to two months instead of throwing out spoiled wine and, in the process, losing money on an unusable product.
Safeguards are a must when it comes to using nitrogen. Rack and Riddle’s Gadd-Coster explained why wineries have to exercise caution to protect their workforce. “It does displace air in enclosed spaces and so is dangerous in that respect. Enclosed space protocols need to be respected.”
Suffocation is a genuine threat to workers if a nitrogen gas leak goes undetected. For this reason, most wineries use gas monitors, portable sensors and other gas detection technology designed to protect workers from oxygen depletion. Illinois-based PureAire Monitoring Systems services a vast array of food and beverage clients, including wineries. The company has a wide range of monitors for specific needs with features that promote ease of operation and longevity, such as a digital screen displaying an instant-read of oxygen levels and a zirconium oxide sensor cell. Its dual oxygen/carbon dioxide model includes both the zirconium oxide sensor cell and a non-dispersive infrared sensor cell.
The use of nitrogen gas is a part of nearly every food and beverage processing industry, including winemaking. For a product whose optimal result depends on the right combination of artisanship and science, wineries are using nitrogen to heighten the taste and quality of their wines as well as their profits.