What is wine on tap?
Quick answer
Wine on tap means serving wine from stainless-steel kegs (10–30 litres) through a draught system pressurised with inert gas — nitrogen or a nitrogen/CO₂ blend. Over 3,500 US restaurants used the format in 2024. It cuts the carbon footprint by roughly 40 % compared to glass bottles and keeps wine fresh for 4–6 weeks once tapped.
Detailed answer
Wine on tap sounds trendy, but the concept is ancient — Romans served wine from pressurised vessels thousands of years ago. The modern version took off in California around 2010, led by companies like Free Flow Wines, which processed over 7 million litres in 2024 and supplied 3,500+ venues.
The setup uses stainless-steel kegs (10, 20, or 30 litres) purged with nitrogen to remove all oxygen. An inert gas — pure nitrogen for still wines, a 70/30 N₂/CO₂ mix for sparkling — pushes wine to the tap. The result: zero oxidation from first pour to last, unlike an open bottle that starts declining within 24–48 hours.
The environmental case is strong. A Portland State University study (2020) found that switching from glass bottles to kegs cuts the carbon footprint by 40 % per litre served. A single stainless-steel keg lasts 30+ years and can be refilled over 300 times, eliminating the 550 g of glass in each standard 75 cl bottle. A restaurant pouring 500 bottles a month saves 275 kg of glass waste.
Europe is catching up. The UK had roughly 800 tap-wine venues in 2024. Belgium is earlier in the curve, but forward-thinking wine bars — especially those focused on by-the-glass service — are exploring the format. A well-managed keg system wastes less than 2 % of wine, compared to 15–20 % from opened bottles in a by-the-glass programme.
The biggest hurdle? Perception. Many drinkers still link 'tap wine' with low quality. In reality, respected estates like Bonterra, Scribe Winery, and Jean-Luc Colombo now offer keg formats. The pitch for restaurants is freshness and sustainability — and the economics don't hurt either, with a 20–30 % reduction in cost per glass.
| Criteria | Glass bottle (75 cl) | Stainless-steel keg (20 L) | Bag-in-Box (3 L) |
|---|---|---|---|
| Carbon footprint / litre | Baseline (100 %) | −40 % | −55 % |
| Shelf life after opening | 24–48 h | 4–6 weeks | 4–6 weeks |
| Waste (by-the-glass service) | 15–20 % | < 2 % | 5–8 % |
| Container reusability | Recycling | 300+ refills (30 years) | Single use |
| Consumer quality perception | High | Improving | Medium |
| Cost per glass (restaurants) | Baseline | −20 to −30 % | −30 to −40 % |