Table of Contents
- Oenological gas formula for wine preservation
- Why argon protects wine after opening
- Choosing a cartridge for wine preservation
- Frequently asked questions
Understanding which oenological gas formula is used in wine preservation cartridges matters to anyone seeking to maintain quality after opening. The formulation explains how oxygen is displaced, why the blend was developed, how it protects wine at a chemical level and which cartridge suits still or sparkling wines, from the first pour to the last.
Oenological gas formula for wine preservation
This formula is the result of oenological work carried out with a specialist gas supplier operating at an industrial level.
The 80% argon and 20% CO2 blend in each argon capsule
Those asking which oenological gas formula is used in wine preservation cartridges will find a consistent industry answer: a food-grade blend marketed as 80% argon and 20% carbon dioxide, developed specifically for still wines. Wikeeps uses a specification of 79% argon and 21% CO2 in its still-wine cartridges, produced in collaboration with Linde Gas. The cartridges are manufactured in the EU to oenological standards, with the OIV gas analysis methods providing further technical context. The full technical detail sits with the oenological gas formula in Wikeeps cartridges.
- Argon proportion: At 79–80% of the blend, argon forms the primary inert barrier above the wine surface. It displaces oxygen without reacting with the liquid.
- CO2 proportion: The 20–21% carbon dioxide component is calibrated to limit the loss of dissolved gas from still wine, supporting freshness without introducing carbonation.
- Oxygen contact: Together, the two gases push oxygen-rich air out of the headspace and limit contact between atmospheric oxygen and the wine surface.
- Standards compliance: The blend is sourced through Linde Gas and produced in the EU to oenological standards.
The specification of 79% argon and 21% CO2 reflects the precision required for this application. The slight difference from the marketed 80/20 figure has no practical consequence for the wine, but it shows that these cartridges are engineered products rather than commodity cylinders. In practice, the difference comes down to consistent gas sourcing and the integrity of the sealing process, which maintains compression at 205 mPA inside each 21 ml unit.
Why food-grade gases matter
The choice of a wine preserver chemical for direct contact with a consumable product carries real regulatory importance. Only food-grade gas, tested for contact with food and beverages, should be used in wine preservation. That requirement keeps contaminants out of the bottle along with the protective atmosphere.
Replacing food-grade gases with industrial-grade alternatives can introduce impurities that alter a wine’s aroma and potentially compromise its safety. The Wikeeps formula is sourced through Linde Gas and manufactured in the EU to oenological standards. An unused cartridge stays effective for as long as its container remains intact.
How the formula limits oxidation
Once opened, wine begins to oxidise. The argon and CO2 blend displaces oxygen-rich air from the headspace of an opened bottle, replacing it with a dense, inert atmosphere that limits further contact between the wine surface and atmospheric oxygen. Independent laboratory testing in France found that, when correctly applied, the blend can preserve opened wine for more than 30 days while maintaining taste, aroma and freshness.
Argon cannot reverse oxidation that occurred before the gas was applied. A wine left open for several days before treatment will not recover its original profile. Conversely, applying the system after every pour renews the protective layer and extends the drinking window. Warmer storage accelerates residual oxidation, so suitable conditions and compatible stoppers also help achieve the preservation period of more than 30 days.
Why argon protects wine after opening
Argon protects wine through both physics and chemistry. Its density, chemical inertness and behaviour inside a closed bottle make it particularly well suited to wine preservation among commonly available inert gases. These properties explain why an 80/20 argon-CO2 blend is used in many still wine preservation cartridges instead of a simpler alternative.
Argon’s dense protective layer
Argon has an atomic mass of approximately 40 u, compared with 32 u for oxygen and 28 u for nitrogen. At approximately 1.38 times the density of air, argon gas sinks towards the wine surface and can displace oxygen. Density alone does not guarantee a stable layer in an opened bottle, however: an argon wine preserver works best when the bottle stays upright and the gas is renewed after each pour.
After each pour, a measured gas injection restores the protective layer above the wine. Oxidative reactions are therefore slowed, which matters most for delicate varieties, Pinot Noir, aged whites and other aromatic still wines that are particularly vulnerable to oxygen contact. Argon has no odour and does not react with the liquid, so the wine keeps its flavour and aroma; oenological uses of inert gases also rely on these properties.
Why CO2 is included, compared with a Coravin capsule
A pure argon capsule is effective for preserving wine, yet the 80/20 blend provides an additional advantage for still wine. Without CO2, a purely argon atmosphere can gradually draw dissolved gas from the wine, producing a flatter, more astringent profile. The calibrated proportion helps limit that loss and maintain freshness during the preservation period.
The Coravin wine preservation system uses pure argon to dispense wine without removing the cork, with a needle passing through the cork and the natural cork resealing after the puncture. Wikeeps cartridges are compatible with Coravin-type systems, using the same 21 ml cartridge format and identical food-grade gas specifications. As a result, the oenological gas blend offers a genuine alternative for owners of those devices. More detail is available on the oenological gas blend used in Wikeeps cartridges, including how gas selection affects preservation outcomes.
Argon compared with other gases
Nitrogen, at 28 u, is lighter than both argon and oxygen. In an open bottle, it circulates through the headspace rather than settling into a stable layer, so more gas is required to achieve comparable protection, which means more gas waste. Purging a bottle with nitrogen can work in closed dispensing systems where oxygen is evacuated first, but it is less efficient for pour-by-pour service at home or in restaurants. Pure CO2 presents a different issue: it dissolves into still wine, forming carbonic acid and adding unwanted fizz that changes texture and aroma.
The 80/20 argon-CO2 blend is the right choice when preserving wine over several sessions and weeks, particularly in still wines where oxidation and loss of dissolved CO2 both matter. In practice, food-grade argon offers the density and inertness needed for reliable cartridge-scale protection. The same principle underpins Wikeeps: a controlled gas barrier protects wine from repeated oxygen contact without changing its character.
| Gas | Atomic/molecular mass (u) | Forms stable barrier? | Suitable for still wine? | Risk to wine |
| Argon (80%) | 40 | Yes, dense, settles above wine | Yes | None, inert, odourless, non-reactive |
| Carbon dioxide (20%) | 44 | Partial, dissolves into wine | Only in calibrated blends | Carbonation if used pure |
| Nitrogen | 28 | No, circulates in headspace | Limited | Higher gas consumption; decarbonation risk |
Choosing a cartridge for wine preservation
Selecting the correct cartridge begins with the wine style: still or sparkling. These two categories require different gas formulas, and using a still-wine cartridge on Champagne, or the reverse, can compromise the wine’s character.
Still and sparkling wine preservation formulas
Sparkling wine preservation calls for a different formula: Bubbl. cartridges use a food-grade gas blend of 80% CO2 and 20% nitrogen, creating a protective atmosphere that limits oxidation without disturbing the wine’s effervescence. The details for Champagne, Cava, Prosecco and other styles are covered under the oenological gas formula in sparkling wine cartridges.
The sparkling-wine formula works under controlled pressure through the Smart Cap system, maintaining bubbles and aromas for more than one week.
- Still wines Use 80% argon and 20% CO2 to displace oxygen and support freshness for more than 30 days with a compatible stopper.
- Sparkling wines Require 80% CO2 and 20% nitrogen, injected at controlled pressure to preserve bubbles and aroma for more than one week.
- Delicate reds and aged whites Benefit from the argon-dominant formula because aromatic compounds are particularly vulnerable to brief oxygen contact.
- Champagne, Cava, Prosecco Require the Bubbl. cartridge and Smart Cap system; the still-wine argon formula is unsuitable for preventing the loss of effervescence.
Each still-wine cartridge from Wikeeps contains 6.5 g of compressed gas in a 21 ml unit, and a single capsule pours and preserves at least 18 glasses of wine across three 75 cl bottles. Each Bubbl. cartridge, by contrast, preserves at least five opened 75 cl bottles of sparkling wine.
Cartridge quality and storage
Cartridge integrity directly affects preservation performance. A quality cartridge should pass a simple shake test with no internal rattling, and show no rust spots, greasy residue, burrs or dents around the gas outlet. Its plastic sleeve cap must also seat cleanly in the dispensing system. Wikeeps cartridges are manufactured in the EU from stainless steel and chromed steel, supplied in packs of five or ten units, and recyclable as household metal waste once empty.
Storage conditions matter too. Keep cartridges in a cool, ventilated area, since heat increases the internal pressure of a compressed-gas unit. Argon is a stable noble gas and does not chemically degrade inside an intact container. As a result, the effective life of an unused cartridge depends on container integrity rather than gas deterioration.
Checking the outlet cap before use is a brief but worthwhile habit. A compromised outlet may indicate gas loss, reducing the number of effective pours per cartridge and weakening the preservation cycle.
Using a preservation system correctly
The Wikeeps Essential Kit includes a French-patented dispenser gun, central dome, preservative caps, spout and filter. It injects an argon-CO2 blend in a controlled manner, allowing wine to be poured while the remaining wine is protected from oxygen. The system is intended for professional and home use, from wine by-the-glass service to occasional bottles, while Wikeeps cartridges use the same format as Coravin-type devices and offer existing users the same food-grade gas formula.
Consistent technique matters as much as cartridge quality to preserve wine across several sessions. Reinject gas after every pour, not only when the bottle is first opened, to sustain the inert atmosphere and prevent the gradual oxygen build-up that shortens wine freshness. From there, store the treated bottle upright in a cool environment, so that the preservation period of more than 30 days remains achievable from first injection to final glass.
Frequently asked questions
What is the best gas for preserving wine after opening?
Argon, about 1.38 times as dense as air, displaces oxygen without reacting with the wine. For still wines, a blend of 80% argon and 20% CO2 works better because the CO2 limits the loss of dissolved gas. Wikeeps cartridges use a specification of 79% argon and 21% CO2, produced with Linde Gas. Nitrogen is lighter and circulates in the headspace, so it gives less efficient protection when a bottle is poured glass by glass.
What gas is used in wine preservation cartridges?
Still-wine cartridges contain a food-grade oenological blend, specified at 79% argon and 21% CO2 in Wikeeps cartridges. Argon has no odour and does not react with the wine, so it leaves flavour and aroma unchanged. Sparkling wine needs a different formula: Bubbl. cartridges use 80% CO2 and 20% nitrogen to keep the wine’s effervescence rather than remove it.
How long can an opened bottle of wine be preserved with an argon cartridge?
Independent laboratory testing in France found that the argon-CO2 blend, when correctly applied, can preserve opened wine for more than 30 days. This depends on reinjecting gas after every pour, using a compatible stopper and storing the bottle upright somewhere cool. One 21 ml Wikeeps cartridge serves at least 18 glasses from three 75 cl bottles.