New wine bottle closure Vino-Lok is taking screwcap and cork prisoners

glass cork 2For a few years now, the screwcap and cork have been battling it out like an Olympic curling match. It’s not particularly riveting for those outside the industry, but wine geeks view it like the gold medal round. Comments often heard about screwcaps: “Easy to open”… “Does it age wine?”… “At least 10% of the wine doesn’t get ruined”. And on and on… the conversation has been repeated endlessly.

But there’s a new classy contestant that’s stealthily coming up the outside lane — really fast. The Vino-Lok (Vino Seal in U.S.), a glass stopper for wine bottles, is putting up a new fight. Invented in Germany in 2004 by Alcoa, it could fulfill the need of a closure for the “connoisseur” (aka wine snob who finds metal closures cheap and lame). Its familiar-sounding advantages come straight from the screwcap playbook: Keeps wine fresh, prevents oxygen from entering the wine and preserves integrity.

But what’s wrong with good ‘ole fashioned cork? A non-toxic chemical substance known as 2,4,6 trichloroanisole — TCA for short — lives in cork tree bark (the stoppers are cut from the skins of mature trees). Bleaching and sterilizing, part of the cork-making process, randomly causes a reaction in the cut cork and releases chemicals that kick off an unfavorable odor. Once the affected cork is placed in the bottle, it intermingles with the wine and the juice takes on the flavor of TCA – wet dog or wet newspaper. Not really scrumptious, eh?

But here’s the worst part – this process takes a while to happen, so the wineries have no way of uncovering the cursed corks until it’s too late – when you pour their wine into your glass. Even though only a small percentage of corks end up contaminated with TCA (from 2 to 10 percent), even 5 percent of a small, 60,000-bottle winery equals 3,000 bad bottles. That’s a helluva lot of waste and customers to lose — because of a 17th century wine closure tradition.

So wineries have been seeking alternatives for years. But the screwcap – despite dogged efforts by wine writers like me who laud praise on it – still wallows in disdain.

Glass corkEnter Vino-Lok.

Words like “elegant”, “innovative” and “fresh” have been used to describe it. It nestles into the bottle like an upscale olive oil stopper, creating a glass-on-glass seal. And it doesn’t require a corskcrew. Dr. Rowald Hepp, winemaker for Schloss Vollrads Winery in Germany, has used Vino-Lok for his award-winning rieslings since 2003. He’s part of a board which researches closures and did comparisons with oak cork, plastic cork, screwcaps and Vin-Lok over a seven year period. He reported that the glass closure showed less variation and more freshness, offering “reliable aging of the wines.”

But will wineries and consumers embrace it? I’ve showed it to several people who find the Vino-Lok chic and different — decidedly more sophisticated than the screwcap. Ed Sbragia from Sbragia Family Vineyards uses it for his whites and you will begin to see it tucked under the foil of more and more white AND red bottles from Australia, California and Germany. But you won’t find it in high-end Italian and Spanish bottles. In an effort to protect their cork production industries, both countries have legislated their quality-designated wines (DOC and DOCG in Italy/ DO and DOC in Spain) must be closed with cork to ensure the award of the designation. But some Italian producers, in what is fast becoming a trend, snub the official regulations and are using glass closures for their lower-level classified (but not lower quality) IGT classifications.

What I learned: Some traditions do change and it’s all about the marketing.



  1. Reminds me of the same glass stoppers we sealed chemical reagents with in organic chemistry lab. hey if it can keep acid potent, it sure is good for wine….sometimes old is new=)

  2. So, how does it work? Insert the glass plug and twist something to lock?
    Very cool.

  3. No twisting… it just fits snugly into the top of the bottle. Glass on glass.

  4. I remember reading about these several years ago. At the time I thought this was a great way to seal a bottle, and I would rate it as interchangeable with cork from a class standpoint. It would look good at tableside, too. I’m surprised more wineries have not adopted these. Do you know how they compare costwise to the Stelvin (screwcap) closures?

    Also, I would be curious as to your personal experience with cork taint. My personal experience is that it is pretty rare. If I were to guess I’d say I notice it in 1 out of 300 or so bottles, a much lower rate than generally posted. Of course, my tasting talents are not as refined as experts in the field, despite the size of my nose.

  5. A winery must make a significant investment in their business in order to make this switch… new bottles that accommodate the Vino-Lok closure and possibly a new bottling line. Much like the stelvin. I don’t know how the cost compares between those two but I would imagine they are comparable.

    As far as cork taint, I experience it quite frequently since I’m very sensitive to the taste and smell of it (and drink frequently). Is it 1 out of every ten bottles? No. But it’s probably 1 out of 50 in my experience.

  6. gerrad callahan

    2 things! they compare poorly pricewise with stelvin (about $1 vs. about $0.30), and the glass on glass issue. that being that cork and glass form a tight (? often) seal, while glass/glass may do the same but where the shape of a stopper might be able to be standardised and precise, the inner neck of a bottle is not as yet so able. that means- will the rate of expansion of the bottle during change of weather match that of the stopper? my physics tells me that is unlikely to be the same allowing room for loss of seal- perhaps! im hoping however that this will prove not to be prohibitive (price) nor the case (leakage) as i think they allow the traditionalists and those interested in avoiding taint – to both be happy.

  7. The price has dropped to .51 per closure making it on par with high end cork. We’ve found similar SO2 levels to screw caps, and the ELVAX O-Ring and cap keep the closure snug in the bottle. It is the top closure by far.

  8. Jeff: do you think American wineries will have the hutzpah to make the switch? Methinks they won’t. So many are still scared of screwcaps but maybe the image of the glass closure can overcome the nervousness. It will be interesting to tell. I’ll ask the winemaker where I work what she thinks.

  9. do all the cusumano nero d’avola vintages have the vino lok instead of cork?

  10. Cindy, likely not. Vino Lok hasn’t been around that long but you’re safe buying a Nero d’Avola from vintage 2009 until 2011.

  11. I found it in a NY wine I buy. I keep the glass corks and use them in corked wine bottles. It fits nice and snug and pops off with a little effort. Also make cute ring holders.

  12. Alright, so I’m going to ask a question, and I don’t mean to sound foolish. As a consumer, I’ve run into these glass corks quite a bit over the last few years, and they are next to impossible to remove from the bottle. Of course, a traditional corkscrew will not work… Is there by chance an easy way to remove them?

  13. Not foolish! Those little suckers are difficult to remove, for sure. I would try running warm water over it before trying to open it, since that might help break the suction power. Make sure you get some water in-between the bottle top and the closure.


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