By: Gerald Dlubala
It’s colorless, odorless and virtually undetectable. As a result, nitrogen is one of the most effective tools for winemakers to use as a combatant against oxidation, spoilage and bacteria growth in their wines. As a result, nitrogen can be used in multiple stages of winemaking and has become one of the best tools for winemakers to have at their disposal. The main reason? Nitrogen is inert and does not readily react with other substances around it. Because of that inertness, nitrogen is an excellent choice to help reduce or delay any damaging oxidation that might otherwise occur.
Additionally, nitrogen is preferred for tank blanketing, equipment purging, pump and filter membrane testing, pressure transfers, must-lifting and more. It also plays an essential role in packaging stability, which is critical with the increased production of single-serve and ready-to-drink container packaging. Finally, and perhaps at its most fundamental level for a winemaker, nitrogen is an economical and valuable way to ensure a wine’s integrity and profile properties while also providing extended shelf life.
Liquid Nitrogen (LN2) dosing is just one of the preferred uses in the winery. For preservation purposes, when LN2 is introduced seconds before sealing the filled bottle, nitrogen replaces the headspace oxygen, reducing the oxygen levels by up to 95 to 98 percent, with a 60 percent reduction in total package oxygen.
Chart Industries Inc. As Easy as Point-and-Shoot
“Nitrogen dosing is prevalent in consumer products across the board, including the ready-to-drink and single-serve segment,” said Christina Marrick, the business development manager for nitrogen dosing systems for Chart Industries Inc. “Wineries now have more packaging options, and whether they are filling glass bottles or aluminum cans, LN2 dosing is beneficial, especially if using screw cap enclosures. Bottles sealed with screw caps contain more head space and oxygen than those with a cork inserted. Dosing with LN2 removes roughly 98 percent of the headspace oxygen, leaving little room for any oxidation.”
“Additionally, LN2 dosing pressurizes the container being filled and sealed,” said Marrick. “When dosed, one-part LN2 warms and expands into 700 parts gaseous nitrogen at ambient temperature. That vaporization process adds pressure to the sealed container, providing rigidity to the walls of the filled container and increasing package stability. That increase in structural integrity allows wineries to use lighter containers with up to a nine-gram reduction in average bottle weight. Applied to the production of an average production line, this equates to about 2.6 million in annual savings.”
Marrick tells The Grapevine Magazine that Chart’s LN2 dosing equipment allows for simple, easy-to-use point-and-shoot operation.
“Using LN2 dosing equipment is really pretty simple,” said Marrick. “Our dosers are set once for the application needed and use sensors to pick up the incoming containers. Once they sense the incoming container, the automated dosers dispense a precisely measured amount of LN2 into the container after filling but immediately before being sealed. The trapped LN2 immediately vaporizes, forcing oxygen out of the container while simultaneously creating pressure and adding rigidity to the container. The dosers are modified for different products and containers through adjustment of dosing times or by using different-sized nozzles. Dosing equipment is installed and used in-line, but on casters, that can be easily moved or relocated for use wherever and whenever needed.”
Chart Industries provides an entire spectrum of potential nitrogen use for wineries, from liquid bulk tank storage to specific application delivery and dosing throughout the production, filling and packaging process. They were the first to provide a complete, turnkey, LN2 dosing system, including dosers, valves, piping and phase separators on through to handling your bulk storage solutions, offering a full line of tanks ranging from portable dewars to the most extensive bulk tank storage options. Their standard cryogenic tank is an industry workhorse, able to be customized to a winery’s specific needs. The tanks can be installed in horizontal or vertical configurations and feature a proprietary insulation system, resulting in a lightweight tank with high thermal performance and extended hold times while offering reduced operational and installation costs.
Vacuum Barrier Corporation Dosing to Meet Your Needs
Vacuum Barrier Corporation (VBC) is a global leader in cryogenics, designing, engineering and fabricating liquid nitrogen (LN2) dosing and piping systems. Lisa Angelini, the marketing manager for VBC, tells The Grapevine Magazine that LN2 dosing systems address the oxidation challenges winemakers have during the packaging process.
“Liquid nitrogen dosing is used pre-filling, as a way to purge oxygen from the empty bottle, or post-filling to remove the oxygen that occupies the headspace, and in some cases,” said Angelini, “winemakers use it in both locations. By using LN2 dosing to flush oxygen out of the bottle, you’re preserving the wine’s intended flavor and bouquet while simultaneously extending shelf life. Additionally, winemakers can reduce, rather than eliminate, oxygen to give them added control.”
The growing demand for single-serve and ready-to-drink options makes the structural integrity of packaging and extended shelf life an increasingly important part of wine packaging and distribution. A consumer only has to browse the shelves at a favorite retailer to notice the market shift.
“The acceptance of canned wine has opened another door to VBC’s LN2 dosing systems within the industry,” said Angelini. “The same LN2 dosing system that the winemaker uses to reduce oxygen in their wines provides packaging stability and integrity. By adding a precisely measured dose of LN2 to the can of non- or lightly carbonated wine, you’re providing the needed pressure to provide structural support in the packaging, reducing transportation and handling damage due to crushed cans.”
For over 60 years, Vacuum Barrier Corporation serves numerous industries, including food and beverage, beer, wine, coffee, cannabis and more. They are committed to delivering safe, defect-free, custom or standard LN2 solutions for your unique application needs.
Production Needs and Intended Use Determines Nitrogen Storage Choice
Bulk storage vessels and accompanying equipment are equally crucial in using nitrogen and must be appropriately sized and fitted to each winery’s consumption needs. You don’t want your nitrogen supplier to deliver to you more than once a week, so a correctly sized nitrogen storage, delivery and dosage system must be designed to meet that goal. Bulk storage vessels are generally available in two forms, larger bulk tanks and smaller portable tanks called dewars, featuring double-walled construction with a vacuum space between the two walls. That vacuum space allows the tank’s outer surface to remain at ambient temperatures while the inner area can contain and hold the proper cryogenic temperatures. Affected piping systems should be similarly insulated and use the same double-walled, vacuum-spaced design to maintain efficiency. The larger bulk tank installations are predominantly located outside the production structure, while the smaller, portable-style storage units are kept inside the winery, closer to where they are needed.
Alternatively, on-premises nitrogen generators offer on-demand nitrogen when needed. Connecticut-based On Site Gas Systems offers precision-engineered nitrogen and oxygen generators across numerous industries. The company notes that although costs associated with setting up a generator on site are higher initially than other options, their long-lasting nitrogen generators typically recover those initial costs many times over in the long run. An on-site generation source simplifies business and increases workplace safety for wineries currently using nitrogen in their winemaking process or looking into the prospect of nitrogen use. Wineries with nitrogen generators on-site can expect to save between 40 to 80 percent compared to the costs of delivered nitrogen, depending on price fluctuations. Additionally, when sustainability is at the forefront of every decision, eliminating the need for diesel delivery trucks helps to reduce your winery’s overall carbon footprint.
How a winemaker ultimately chooses to obtain and access a nitrogen supply is a decision that is unique to each winery and generally dependent on specific qualifiers, such as the size of the winery, production numbers, the amount of nitrogen the winemaker will use, expected cost and return on investment offered by the different choices.
For example, The Cave Vineyard and Distillery, located in historic St Genevieve, Missouri, runs a 20,000-bottle-a-year operation and does not offer single-serve options. Even though they would like to have their nitrogen source on-site someday, their current production and packaging operations don’t warrant the expense. Instead, like many smaller wineries, they use portable dewars for their nitrogen source. With four dewars on the premises at all times, they use two for purging empty bottles and clearing headspaces of oxygen before sealing. The remaining dewars are used as additional storage to prevent the winery from running out.
Alternatively, the award-winning Augusta Winery in Augusta, Missouri uses nitrogen in all phases of its winemaking and has its own nitrogen generation system on-site to produce nitrogen on demand. While admittedly being costly upfront, the winery says the system paid for itself within three years. Their expanded nitrogen use, including running nitrogen in all related lines to reduce the oxygenation that occurs during routine and standard liquid transfers, helps keep the harmful effects of oxygenation out of their wines at every phase of production, movement, filling and packaging.
Safety Is Always Key
Safety precautions in a production setting are always the primary priority, and the use and handling of LN2 are no different. Nitrogen displaces oxygen-rich air in enclosed spaces, so any enclosed area with a nitrogen leak can create an oxygen-depleted atmosphere. Enclosed spaces always demand specific protocols that must be respected and adhered to by any employee or contractor entering those designated spaces. Wineries and production facilities that use nitrogen in their processes should always use monitors, portable sensors and any other available means of dangerous gas detection technology designed to warn of oxygen deficiencies.