By: Cheryl Gray
The air we breathe is home to a free, abundant and primary weapon that wineries use to combat the ever-present threat of oxidation.
That weapon is nitrogen, which makes up about 80% of the Earth’s atmosphere. Winemakers harness the benefits of this colorless, odorless, inert gas to prolong the shelf life of their products by guarding them during production and storage. In short, nitrogen protects what is most important to winemakers—the wine’s taste, aroma, and quality.
The question of how nitrogen functions best in any winery is answered by companies that are experts in the field. Among them is Vacuum Barrier Corporation, a cryogenics industry leader based in Woburn, Massachusetts. VBC designs, engineers and fabricates liquid nitrogen dosing and piping systems for wineries, breweries and other industries across the globe.
The company has a 60-year history of providing its clients with custom-built and standard solutions for liquid nitrogen. Wineries use VBC’s signature Nitrodose injection systems in multiple applications. Its piping systems include the stainless Semiflex, Nitromatic dewar fill and Cobraflex. CobraFlex is a liquid nitrogen hose made of stainless steel, deriving its name in part from its extremely flexible outer wrap. A clean-in-place feature is available for all piping options, as are sensor control separators and modulating valve phase separators.
Jim Fallon is an Application Engineer for VBC. He explains that liquid nitrogen use in wineries is versatile and provides many solutions in real-time, helping to delay or eliminate oxygen contamination before it can start.
“The main advantage of nitrogen is that it’s inert and won’t easily react with other substances. This means it can be used to reduce or delay the oxidation of the product. It essentially replaces a significant amount of the oxygen found in ‘air’ at different stages of the manufacturing and packaging process.”
VBC works specifically with liquid nitrogen to deploy it for common uses such as purging wine bottles before filling and removing oxygen in the headspace before capping. Fallon describes how liquid nitrogen is key in this process, known in the wine industry as flushing.
“Flushing can be an important step in maintaining the freshness of any organic material,” he says. “Removing oxygen from a storage container or bottle will help to extend the shelf life of the product. Liquid nitrogen expands to 700 times its volume as it evolves into a gas. That rapidly expanding gas drives air out of the container.”
Another use for nitrogen in wineries is sparging, which removes the oxygen that has dissolved in wine during various points in production. Since it is inert, nitrogen doesn’t react with the wine and, as a result, won’t alter the flavor and bouquet intended by winemakers. Fallon points to argon as another inert gas that wineries use for sparging. Another option is carbon dioxide, but Fallon warns that its use presents some challenges.
“Carbon dioxide tends to be more reactive and tends to alter the profile of the wine, which may or may not be desired,” he says.
Fallon adds that nitrogen is also typically used in blanketing, which functions just like it sounds. Nitrogen, or argon, covers an area or container to help protect the wine by keeping oxygen out.
O2 N2 Site Gas Systems
Giving wineries the option to generate nitrogen in-house and on-demand is the expertise of O2 N2 Site Gas Systems. In business since 1987, the Connecticut-based company provides a range of generator options, including Membrane Nitrogen Generators and Pressure Swing Adsorption Nitrogen Generators. The company says that adsorption is the physical separation of molecules, not a chemical one.
The PSA generators produced by O2 N2 Site Gas Systems separate nitrogen from oxygen in the air. A PSA generator system performs this task using a pressurized vessel containing either carbon or zeolite. Nitrogen is trapped while oxygen is safely released back into the atmosphere. According to the company, this method provides 99.9995% of nitrogen. Other cost-saving features include an automatic standby mode when no gas is needed. The generator will also continuously check the pressure to make certain that the gas generated matches nitrogen demand.
The company’s membrane technology also uses pressurized air. That air is forced through membranes that act like filters with tiny holes small enough to allow oxygen molecules to pass through, leaving the nitrogen molecules behind. The process continually generates nitrogen at the desired flow and purity levels.
Chart Industries is a global manufacturer offering a wide range of products for multiple nitrogen applications in wineries. The company produces equipment engineered to provide technologically advanced solutions in virtually all areas of industrial gas applications. Its portfolio of products includes not only engineering but also service and repair.
Located in New Prague, Minnesota, the company has a 160-year history of being at the forefront of technological advances. In 2021, it acquired Cryo Technologies, a leading manufacturer of cryogenic systems that Chart Industries has worked with for more than 20 years. The acquisition brings a team of highly skilled, richly experienced engineers and designers with a deep knowledge of cryogenic system design.
Chart Industries manufactures liquid nitrogen dosing systems for several industries, but its primary focus for wineries is using nitrogen for cleaning equipment and product storage. Richard Rosik, Sales Manager for Chart Industries, describes how the company’s products integrate well into wine production, including applications for storage, bottling and cleaning production lines.
“The cleaning of the equipment is very important to ensure a sterile environment as well as line changes from product to product. The Chart Nitrogen Doser is designed for use in these types of environments. Our liquid nitrogen dosers are specifically used to displace oxygen in the headspace by allowing the liquid to vaporize inside the bottle, pushing out the oxygen and other impurities.”
Chart Industries also provides wineries with bulk storage options that preserve wine by protecting it from oxidation through the sparging process. Rosik says the equipment is ideal for these functions.
“Because of Chart’s diversified portfolio, although our nitrogen dosers aren’t specifically used in the sparging process, our Storage and Vaporization equipment is. Our liquid cylinders, MicroBulk and bulk tank offerings are ideal for these applications.”
The company’s bulk tank products range in size from 1,500 to 264,000 gallons and can accommodate maximum allowable working pressures ranging between 175 and 500 PSIG. The tanks come in horizontal and vertical configurations and feature a stainless-steel inner vessel and a carbon steel outer shell with an integrated support and lifting system for easy transport and installation. The insulation system of the tanks promotes high thermal performance, long hold times, minimal life-cycle costs and reduced weight to cut operational and installation costs.
For smaller operations, Chart offers the Perma-Cyl MicroBulk System. This system is designed for small and medium wineries to benefit from onsite gas delivery of liquid nitrogen, with tank sizes ranging from 61 to 1,840-gallon capacities. Its primary function is to cut the cost of time and money lost in the cycle of exchanging cylinders. Things like loss, damage, keeping track of cylinder inventory, even losing the use of residual gas left in the cylinder are costs that are difficult, if not impossible, to recoup.
For more complex operations, O2 N2 Gas Systems provides clients with custom-engineered nitrogen generation systems. The company develops with a cost-savings approach in mind for wineries and other industries that want onsite, on-demand nitrogen generation. It offers all facets of systems design technology, assessing individual client needs for the short and long term.
Whether liquid nitrogen or nitrogen generated from the air, experts say this inert gas is by far the most popular choice for wineries guarding themselves against oxidation. While there are other inert gases to use, such as argon and even carbon dioxide, wineries use nitrogen because of cost, accessibility and the kind of wine they produce.