Canned wine is rapidly gaining popularity in the market, particularly among young consumers who appreciate its convenience, modern design, and recyclability.
This trend is especially noticeable during spring and summer, when outdoor events such as picnics, concerts, and beach outings favor easy-access packaging and individual servings over traditional glass bottles.
The Appeal of Canned Wine
The rise of canned wine can be attributed to several factors:
- Convenience: Cans are lightweight, portable, and do not require a corkscrew, making them ideal for on-the-go consumption.
- Design: The sleek, modern look of cans appeals to younger consumers who value aesthetics and innovation.
- Recyclability: Aluminum cans are highly recyclable, aligning with the eco-conscious values of many consumers today.
The Odor Challenge
Despite its growing popularity, canned wine has encountered a significant marketing challenge: some consumers have reported a rotten egg smell when opening the cans. Although the wine's taste and quality remain unaffected, the unpleasant odor has raised concerns among producers.
Investigation by Cornell University
To address this issue, a coalition of New York wineries enlisted the expertise of Cornell University's food science department. Professors Dr. Gavin Sacks and Dr. Julie Goddard, along with their team, began investigating the problem in 2018. Their research, published in the American Journal of Enology and Viticulture, has uncovered the cause of the odor and is paving the way for innovative solutions.
Identifying the Problem
The Cornell team discovered that the culprit behind the odor is a chemical reaction between sulfur dioxide (SO2) and aluminum. SO2, present in wine in small amounts (between 0.5 and 1 parts per million), serves as a preservative and combats oxidation. However, when SO2 interacts with aluminum over time, it produces hydrogen sulfide (H2S), known for its rotten egg smell.
Dr. Sacks explained, "We noticed that in wines with more than 0.5 ppm molecular SO2, there were considerable increases in H2S, the rotten egg odor, within four to eight months."
Mitigating the Odor
Armed with this knowledge, the Cornell team provided immediate recommendations to winemakers. They suggested aiming for the lower end of SO2 levels to minimize the formation of H2S. However, completely removing SO2 was not a viable solution due to its essential role in preventing oxidation and microbial growth.
Dr. Sacks noted, "We start by suggesting that wineries aim for the lower end of what they're usually comfortable with. Yes, there is a chance of having more rust problems. But the good news is that cans provide an airtight seal. They are not likely to let air in, if canning is done correctly, which is why brewers love them. It's great to prevent oxidation."
Consumer Preferences and Market Trends
Interestingly, the odor issue is more prevalent in white and sparkling wines than in red wines. Red wines typically have lower molecular SO2 levels, which reduces the likelihood of the chemical reaction. Additionally, the perception that canned wine is less serious or premium has led producers to predominantly can white wines, rosés, and sparkling wines—those most susceptible to the odor problem.
Dr. Sacks highlighted this irony, stating, "Molecular SO2 levels are typically lower in red wines than in white wines. There is an irony in molecular SO2 being the culprit for odor in canned wine. Because consumers generally associate cans with less expensive, less serious wines, many companies don't put their red wines in cans."
Innovative Solutions: Polymers and Can Liners
To combat the SO2 issue effectively, the Cornell team has turned to innovative materials—specifically, polymers. With new funding from the US Department of Agriculture's National Institute of Food and Agriculture, they are developing recyclable, food-grade polymers for lining aluminum cans. These polymers aim to prevent the chemical reaction that produces H2S while ensuring the wine remains shelf-stable.
The team has also collaborated with Dr. Héctor Abruña, a professor of chemistry, to design these can liners. Their focus includes maintaining recyclability, keeping manufacturing costs low, and preventing other potential chemical reactions with the wine.
Commitment to Improvement
While the research is ongoing, the Cornell team remains dedicated to enhancing the quality of canned wine. Dr. Sacks expressed his enthusiasm, saying, "I thought aluminum cans were boring until I started working on them. The current generation of wine consumers, who are now coming of age, want a drink that is portable and that they can take to a concert or to the pool. That doesn't describe a wine in a corked glass bottle very well, but it does describe a can very well."
As canned wine continues to capture the market's interest, addressing the odor issue and ensuring the product's quality will be crucial. With the ongoing efforts of the Cornell research team, the future of canned wine looks promising, combining convenience, innovation, and sustainability.