To produce long-lasting and great tasting wines, winemakers need to ensure that the product stays fresh for as long as possible. By integrating nitrogen into the process, industrial gas suppliers such as Oxair Gas Systems Ltd (Oxair) are developing technology that helps preserve colour, flavour and aroma of any wine prior to corking or capping the bottle.
When improperly preserved, wine can be subject to oxidation, bacteria and spoilage. By introducing nitrogen during the bottle or can filling process to displace the natural oxygen present in the headspace of the containers, winemakers can better control oxidation, increasing the shelf life.
Onsite nitrogen generating technology such as pressure swing adsorption (PSA) systems can provide manufacturers with nitrogen on tap throughout the three stages of the production process: flushing, sparging and blanketing.
Flushing: When grape juice and wine is channelled through containers, pumps, vats and hoses, higher quantities of oxygen and bacteria can build up in the equipment. By flushing out the components with nitrogen oxygen is displaced, preventing oxidation reactions.
Sparging: During fermentation and aging, oxygen can dissolve in the wine. To release the oxygen, nitrogen is bubbled into (or ‘sparged’) into the brew.
Blanketing: When nitrogen is used to create a layer, or blanket, above the surface of the wine that protects it from the lighter oxygen molecules.
According to Oxair, its technology enables producers a greater degree of self-sufficiency in addition to cost benefits against handling of liquid nitrogen tanks, allowing them to turn supplies on and off as and when required.
“This means they can accommodate seasonal or fluctuating production schedules, such as the surge in demand seen during pandemic lockdowns and the effects of climate change on wine-growing regions,” said the company in a statement.
Commonly used in a range of industrial sectors, including marine, electronics, food and beverage, metal fabrication, pharmaceuticals and oil and gas, PSA technology produces inert gas at low pressure, removing the safety hazards associated with high pressure gas cylinders and bulk cryogenic liquefied gas.
It works by allowing molecules of oxygen to diffuse into the pore structure of the adsorbent (often made from zeolite), while nitrogen molecules flow upwards to the top of the adsorber vessel.
Once the regeneration stage is reached, the adsorbed components are released into the atmosphere and the process is then repeated.
“Nitrogen generators and membrane units give winemakers complete control of a permanent supply of nitrogen rather than being at the mercy of deliveries, which can be affected by poor transport connectivity and extreme weather events,” said David Cheeseman, Director at Oxair.
“Using the equipment eliminates oxygen ensuring fabulous tasting wine from every harvest.”