How to Clean Old Wine Bottles Safely

The honest answer to how to clean old wine bottles is that you usually should not. Cleaning can inadvertently damage their provenance and marketability. That in turn diminishes their value. You might aim to improve a bottle's appearance. Aggressive or improper cleaning can instead lead to label damage. The Australian Wine Research Institute (AWRI) lists label damage as a factor in visual assessments for heat-related damage. Such physical damage does not necessarily imply that the quality of the wine has also been affected. It will obviously affect the appearance, and therefore the marketability, of the wine, states the AWRI. Instead of cleaning, focus on optimal storage conditions. Good storage preserves both the wine and its exterior. Maintain a cool, dry environment: Amon and Simpson (1986) recommend 15-20°C. Protect bottles from light and excessive humidity. That prevents the issues that might tempt cleaning, such as mold or label deterioration. Prioritize preservation over superficial cleaning. It safeguards your investment and avoids unintended consequences. You can learn more about how external factors impact value on our guide to selling fine wine.

What storage conditions can damage a wine bottle's appearance?

Several environmental factors can visibly affect a wine bottle. Each one can impact its marketability. The Australian Wine Research Institute (AWRI) notes that visual assessments for heat-related damage cover several signs. Those are leakage, closure damage, wine travel or seepage on corks, increased ullage, and label damage. The AWRI also states that physical damage does not necessarily imply that the quality of the wine has also been affected. Such damage includes leakage of wine and/or movement of cork stoppers due to thermal expansion. It will obviously affect the appearance, and therefore the marketability, of the wine. Exposure to excessive humidity can damage wine labels. Damaged labels may hinder identification or hurt potential resale value. Understanding wine ullage levels is also crucial for assessing bottle condition. For a broader view of how market factors influence value, consider exploring the live fine wine market index.

How does temperature affect bottled wine and its closure?

Temperature is a critical factor in wine storage. It directly influences both the wine's quality and the integrity of its closure. Excessive storage temperatures will have a marked effect on the shelf life of bottled wine. They can see rapid ageing and significant deterioration of the product, as stated by the AWRI. Marais (1986) observed faulty flavours and decreasing overall quality after 12 months’ storage of wine at 30°C. Temperatures in excess of 40°C will induce visual and sensory changes to a wine in only a matter of days, according to Ough (1986). In general, any storage place where the temperature exceeds 25°C for long periods and 40°C for short periods can affect wine quality, Ough (1992) notes. Too high a temperature can spoil the wine, in excess of 77°F (25°C) over long periods. The wine may become "corked" and develop off-flavors that taste raisiny or stewed.

Avoid thermal cycling, where temperature varies significantly, Hirlam (2019a,b) advises. Exposure to temperatures significantly greater than ambient can cause leakage of wine. It can also move cork stoppers, through thermal expansion of the wine, according to the AWRI. A study by Chanut et al. (2023) looked at microagglomerated cork stoppers. At 35°C, a temperature easily reached during bottle shipping, a significant transfer at the glass-cork interface started to occur beyond 9 months of storage. At 50°C, this shift already occurred within the first 3 months of storage. It led to tremendous oxygen transfer at the glass-cork interface. That transfer approached the diffusion coefficient of oxygen in the air after 6 months, indicating leakage, Chanut et al. (2023) report. Temperatures that are too cold can make the wine freeze and expand. That pushes the cork out or cracks the bottle. More oxygen then reaches the wine.

What impact does light have on wine and bottles?

Light exposure can significantly affect wine quality and appearance, particularly for light-bodied white wines. Light exposure can affect the taste of a wine. It does so through the production of volatile sulfur compounds, known as ‘lightstruck’ flavour, the AWRI notes. Maujean and Seguin (1983) demonstrated that ‘lightstruck’ flavour is due to the formation of volatile sulfur compounds. Dozon and Noble (1989) exposed still and sparkling white wines, bottled in green glass, to light from fluorescent lamps. That exposure produced the lightstruck flavour. The intensity of the flavour was statistically significant in the still and sparkling wines. That took exposure for 31.1 hours and 18 hours, respectively. In comparison, the same wines stored in clear glass developed a statistically significant level of the off flavour much sooner. That took only 3.3 hours and 3.4 hours, respectively, Dozon and Noble (1989) reported. Sensory assessment of the affected wines used descriptive analysis. It showed a decrease in ‘citrus’ aromas. It also showed an increase in ‘cooked cabbage’, ‘corn’, ‘wet wool/wet dog’ and ‘soy/marmite’ aromas, Dozon and Noble (1989) found.

Direct sunlight or incandescent light can adversely react with phenolic compounds in wine and create "wine faults". Light-bodied white wines run the greatest risk from light exposure. For that reason they often come in tinted wine bottles that offer some protection from light. Wines in clear, light green and blue colored bottles are the most vulnerable to light. They may need extra precautions for storage. Light exposure carries another risk. It can exacerbate copper instability in susceptible white wines, leading to haze, the AWRI notes. The AWRI recommends treating white wines with a copper concentration greater than about 0.5 mg/L as likely to be susceptible to copper haze. Above this arbitrary limit, protection from light will only delay the inevitable. Rankine (1989) indicates that amber glass is most effective in excluding wavelengths below about 450 nm, according to the AWRI.

How important is humidity for wine storage?

Humidity plays a role in preserving cork enclosures and preventing label damage. Wines with cork enclosures need some degree of humidity to stop them drying out. That holds even when bottles lie on their sides. Should the cork begin to dry out, it can allow oxygen to enter the bottle. That oxygen fills the ullage space and may spoil or oxidize the wine. However, excessive humidity can also damage wine labels. Damaged labels may hinder identification or hurt potential resale value. Wine experts such as Jancis Robinson note that 75% humidity is often cited as ideal. They add that very little research definitively establishes an optimal range. Tom Stevenson recommends keeping wine out of a refrigerator. The refrigeration process often includes dehumidifying, which can quickly dry out corks. Alexis Lichine contends that low humidity can still be detrimental to premium wine quality. The risk is the cork drying out. The Comité Champagne recommends high and constant humidity, between 60% and 80%, for storing Champagne bottles. Chanut et al. (2023) note that cork-based closures need relative humidity above 50% for good elasticity. Above 80%, the risk of mildew formation on the outer surface of cork increases.

Does bottle orientation affect wine aging and cork integrity?

Bottle orientation during storage has drawn research attention. Recommendations vary depending on the wine type. For most wines with cork enclosures, storing bottles on their sides is common. The practice is thought to keep the cork moist and prevent it from drying out. However, research in the late 1990s suggested a slight angle instead of a completely horizontal position. That angle lets the cork keep partial contact with the wine, so it stays damp. It also keeps the air bubble formed by a wine's ullage at the top. The result may be a slower and more gradual oxidation and maturation process. The AWRI cites Mas et al. (2002). They investigated the impacts of different alignments on bottles sealed with six different closures, for a white and a red wine. After 24 months, wines stored upright had higher yellow/brown colour (measured by OD420nm absorbances) than those stored horizontally. The differences were not significant. The study showed higher oxidation for upright samples sealed with agglomerated cork stoppers. White wine samples showed elevated acetaldehyde levels from the 3-month timepoint onwards, Mas et al. (2002) found. Skouroumounis et al. (2005) investigated the developmental characteristics of a wooded Chardonnay and a Riesling. Bottle orientation (horizontal or upright) had little effect on the chemical composition and sensory properties of the two wines across a 60-month period.

For Champagne and other sparkling wines, upright storage is a common recommendation. The internal pressure from the trapped carbonic gas provides enough humidity and protection from oxygen. Caterer Magazine claims that the Comité Interprofessionnel du Vin de Champagne (CIVC) shares this preference. It found that Champagne stored on its side aged more quickly. Oxygen seeped in after the Champagne corks lost their elasticity through contact with the wine. However, the Comité Champagne itself still recommends storing Champagne on its side in a cool, dark, draft-free place with generous humidity. A study by Chanut et al. (2023) tested two storage positions. Vertical storage puts the stopper in contact with the vapor phase; horizontal storage puts it in contact with the liquid phase. Position had no significant influence on the oxygen transfer through microagglomerated cork stoppers. The same held at the glass-cork interface, over a 24-month aging period at 20°C.

What are the effects of vibration on stored wine?

Anecdotal information suggests vibration contributes to accelerated aging with adverse effects. This remains an area with relatively little research data. A study cited found that vibrations of different frequencies have distinct effects on wine chemistry. This study concluded that "Vibration could be used to accelerate the ageing of wine, but in most cases, this may lead to negative effects on wine quality. Therefore, to store red wines with limited changes in physicochemical properties, vibrations should be minimized." The Comité Champagne recommends protecting Champagne bottles from vibrations during storage.

What are the recommended ideal storage conditions for fine wine?

To best preserve fine wine, combine stable temperature with appropriate humidity. Add protection from light and vibration. Amon and Simpson (1986) recommend keeping the cork in contact with the wine. They also advise a cool (15-20°C), dry location, according to the AWRI. The AWRI's Technical Note TN09 recommends insulated and/or temperature-controlled storage. Those conditions minimize fluctuations in both temperature and humidity. Most experts, such as Jancis Robinson, recommend constant temperatures between 50 and 59°F (10 and 15°C). Tom Stevenson speculates that 52°F (11°C) may be the most ideal temperature for storage and aging. Karen MacNeil recommends keeping wine intended for ageing in a cool area at a constant 55°F (13°C). Wine tolerates temperatures as high as 69°F (21°C) without long-term negative effect.

For humidity that climate-controlled wine storage maintains moderate levels of 55% to 75%. That range avoids cork shrinkage and leakage in dry conditions, and mold and contamination in overly moist ones. The Comité Champagne recommends a constant temperature of between 10 and 15°C for Champagne. It also advises high, constant humidity between 60% and 80%. The Comité Champagne further advises protection from light, vibrations, and odours. In the cellar, corrugated boxes or wooden crates protect wines from direct light. These conditions are crucial for fine wine investment and proper wine storage. You can also use our landed cost calculator to understand the full cost of acquiring and holding wine.

Summary of Recommended Storage Conditions

Factor	AWRI (General)	General guidance	Comité Champagne (Champagne)	Chanut et al. (Cork Study)
Temperature	Cool (15-20°C), minimize fluctuations	Constant 10-15°C (J. Robinson), 13°C (K. MacNeil)	Constant 10-15°C	20°C stable, 35°C causes interface transfer >9 months, 50°C causes leakage >3 months
Humidity	Dry location, minimize fluctuations	Moderate (55%-75%)	High and constant (60%-80%)	>50% for cork elasticity, >80% risk of mildew
Light	Avoid exposure, amber glass effective	Store in corrugated boxes/wooden crates, tinted bottles	Protected from light	Green bottles offer greater protection
Orientation	Cork in contact with wine (Amon & Simpson)	On side (general), slight angle (some research), upright for Champagne	On side	No significant influence on oxygen transfer (microagglomerated corks at 20°C)
Vibration	Avoid thermal cycling (Hirlam)	Minimize (study cited)	Protected from vibrations	Vibrations can impart sensory modifications (study cited)

Understanding the nuances of wine storage and how external factors impact your bottles is key to preserving their value.