What type of keg do I need to dispense beer or beverages on tap

|David Varela Naranjo
Tipos de barriles para dispensar cerveza y bebidas por grifo en instalaciones profesionales y domésticas - Install Beer
Practical guide · Choosing a keg and dispensing system

What type of keg do I need to dispense beer or beverages on tap

Choosing the correct keg is the first step for a beer or beverage on-tap installation to work well. The keg determines the coupler, gas, pressure, cooling, tubing, connectors, tap and cleaning. That’s why it’s not advisable to buy loose components without first knowing which beverage will be served and in what format it will arrive.

Metal keg KeyKeg Cornelius Cask Bag in Box PET CO₂ and pressure Cooling and cleaning
Tipos de barriles para dispensar cerveza y bebidas por grifo
Metal kegs are still the most common format in hospitality, but they are not the only option for dispensing beverages on tap.

What type of keg do I need and which is best suited for me

To dispense beer or beverages on tap you can use a metal keg, KeyKeg, Cornelius, cask, Bag in Box, PET keg or tank. The choice depends on the beverage, carbonation, volume, gas, pressure, cooling, coupler, cleaning, logistics and on whether the system will be domestic, professional or for events.

Quick answer: which keg to choose for your situation

For commercial beer in bars and restaurants, the most common option is the reusable metal keg. For craft beer, wine, vermouth, kombucha, cider or mead in non-returnable distribution, KeyKeg or a keg with an inner bag may be of interest. For trials, homebrewing and small batches, the Cornelius is usually the most practical format. For cask ale, cask is used. For wine, vermouth, cocktails or still drinks, Bag in Box or a tank can be considered.

The decision should not be based only on litres or price. You must check coupler, gas, pressure, cooling, tubing, tap and cleaning.

Guide contents

Quick table: which keg do I need

Use or beverage Recommended format Main advantage What to check before buying
Bar or restaurant with commercial beer Reusable metal keg Widespread format, robust and compatible with regular suppliers. Valve type, A/D/G/S/M/L coupler, CO₂ or blend, cooling and cleaning.
Homebrewing or product trials Cornelius / Corny Keg Easy to fill, clean, carbonate and reuse. Ball Lock or Pin Lock, gas, liquid, regulator, tubing and tap.
Craft beer with no container return KeyKeg, PolyKeg, Petainer or other PET Lighter logistics, useful for distribution or export. Coupler, maximum pressure, whether it has an inner bag and how it is depressurized.
Wine, vermouth or a beverage sensitive to oxidation KeyKeg, Bag in Box or compatible tank It can limit contact with oxygen if the system is well designed. Inert gas, temperature, materials, cleaning and rotation.
Kombucha, cider or mead Cornelius for testing; KeyKeg or compatible keg for hospitality Allows you to validate carbonation, pressure and service on tap. Acidity, sediment, residual sugar, pressure, tubing and tap.
Cask ale or traditional English service Cask Traditional service by gravity, cask tap or hand pump. Temperature, ventilation, hand pump, sparkler and fast rotation.

Reusable metal keg

The reusable metal keg is the classic format of the brewing industry. It is common in bars, restaurants, breweries, events and distributors. It is usually made of stainless steel and works with a compatible keg coupler and gas pressure to push the beverage.

There are European formats, wider and lower, and DIN formats, narrower and taller. Common volumes range between 20, 25, 30, and 50 liters, although other formats may exist depending on supplier and market.

Barriles metálicos de cerveza conectados en instalación profesional
Metal kegs in professional installations: the usual format in bars, restaurants and high-turnover breweries.
When to choose it
  • Beer from a traditional supplier.
  • Hospitality with regular rotation.
  • Events with commercial kegs.
  • Installations with container return.
  • Systems with coupler and CO₂ already defined.
What you need
  • Coupler compatible with the valve.
  • Gas regulator.
  • Gas and beverage tube.
  • Proper cooling.
  • Tap and line cleaning.

Cornelius keg or Corny Keg

The Cornelius keg, also known as Corny Keg, is very popular in homebrewing and product testing. Unlike commercial metal kegs, it is not tapped with a type A, D, G or S coupler, but with specific gas and liquid connectors.

The most common systems are Ball Lock and Pin Lock. It is important to distinguish the gas connector from the liquid connector, because they do not serve the same function and must not be interchanged.

PET kegs, KeyKeg and kegs with inner bag

PET and single-use kegs have become especially widespread for craft beer, export and alternative beverages. They can reduce weight, simplify logistics and avoid returning containers. However, not all plastic kegs work the same way.

Some formats work with the beverage in direct contact with the container, while others incorporate an inner bag. In systems like KeyKeg, the beverage can be separated from the propellant gas, which can be interesting for wine, vermouth, kombucha, cider, mead or other sensitive drinks.

Barriles PET y barriles de un solo uso para cerveza y bebidas
Plastic and PET kegs: lightweight options for distribution, export or projects with no returnable packaging.

Not all single-use kegs are used the same way

A single‑use keg must not be reused, refilled or cleaned like a metal keg if the manufacturer does not allow it. Before installing it, confirm maximum pressure, coupler, depressurisation and disposal recommendations.

Cask, wooden barrels, and traditional service

Cask is used for cask ale, real ale and traditional English service. It can be served by gravity, through a cask tap or with a hand pump. It does not work the same way as carbonated beer in a pressurized keg.

There are also wooden kegs for very specific applications, although in modern dispensing they are less common than metal, PET or inner-bag systems.

Barriles metálicos y barriles de madera para cerveza
Metal and wooden kegs: two different approaches to beer storage, logistics, and service.

Bag in Box and tanks for beverages on tap

Bag in Box is not a beer keg, but it can be a useful solution for wine, vermouth, pre-mixed cocktails, syrups, mixers or still beverages. Tanks or service vessels can also be used when working with batches, premix, events or large-volume systems.

The key is that the dispensing system is compatible with the drink. For carbonated or foamy drinks, Bag in Box is usually not the first choice. For wine, vermouth, or cocktails it can work very well if oxidation, temperature, pump, cleaning, and materials are properly controlled.

Which keg to choose according to the drink

Beverage Indicative format Critical system Common mistake
Carbonated lager, IPA or ale Metal keg, KeyKeg, PolyKeg, Petainer or Cornelius depending on scale. CO₂, correct coupler, cooling and line balance. Using incorrect pressure or an incompatible coupler.
Stout or creamy beer Keg compatible with mixed gases. CO₂/N₂ blend, stout tap and pressure. Serving with an unsuitable tap or gas.
Wine KeyKeg, Bag in Box, tank, or stainless system. Oxidation, temperature, inert gas and cleaning. Treating it like carbonated beer.
Vermouth KeyKeg, Bag in Box or tank. Sugar, aromas, oxidation and cleaning. Not cleaning the line frequently enough.
Kombucha Cornelius for tests; KeyKeg or compatible keg for hospitality. Acidity, carbonation, sediment, material and pressure. Using unsuitable materials or pressure.
Pre-batched cocktails Bag in Box, tank or premix system. Viscosity, sugar, pulp, pump and cleaning. Not planning for blockages or intensive cleaning.

Not sure which keg you need?

Tell us what drink you want to serve, what volume you’ll have, and whether it’s for home, bar, restaurant, event, or production, and we’ll help you define keg, coupler, gas, cooling, tubing, tap, and cleaning.

Ask which keg I need See keg couplers

What to buy along with the keg

Need Recommended product Internal link
Connecting a metal keg Coupler type A, D, G, S, M or L depending on valve. Keg couplers
Connect KeyKeg KeyKeg coupler, depressurizer and adapters. KeyKeg and accessories
Connecting a Cornelius Gas and liquid Ball Lock or Pin Lock connectors. Cornelius connectors
Join tubes and components Fittings, connectors, adapters and check valves. Connectors and fittings
Transporting beverage Food-grade tubing suitable for beverage and pressure. Dispensing tubes
Serving into the glass Tap, tower, drip tray and accessories. Tap for beverages
Maintaining hygiene Cleaning keg, adapters and cleaning products. Cleaning and maintenance

Checklist before choosing a keg

  • Define which beverage will be dispensed.
  • Confirm whether it is carbonated, nitrogenated, still, acidic or sugary.
  • Choose format: metal, KeyKeg, Cornelius, PET, cask, Bag in Box or tank.
  • Identify coupler, connector or adapter.
  • Define CO₂, blend, nitrogen, air, inert gas or pump.
  • Check the maximum pressure of the container.
  • Size the cooling system according to consumption and distance.
  • Plan for cleaning the line, tap and connectors.

Frequently asked questions about which keg to choose

Which keg do I need for a beer tap at home?

For home or homebrewing, a Cornelius with Ball Lock or Pin Lock connectors, CO₂ regulator, tubing, tap and cooling system is usually practical. You can also use commercial kegs if you have the compatible coupler.

Which keg is used in bars and restaurants?

The most common option is the reusable metal keg with compatible coupler, CO₂ or mixed gas regulator, cooling and beverage line to the tap.

Is KeyKeg suitable for beer and other beverages?

Yes. KeyKeg can be used for beer, wine, vermouth, kombucha, cider, mead and other beverages, as long as the coupler, pressure, temperature and cleaning are properly managed.

Is Bag in Box suitable for beer?

It is not usually the standard format for carbonated beer. Bag in Box is more suitable for wine, vermouth, syrups, mixers, cocktails or still beverages.

Can Install Beer help me choose the system?

Yes. Install Beer can help you choose keg, coupler, gas, cooling, line, tap and cleaning according to beverage, use and serving volume.

Technical note: exact compatibility depends on container, valve, beverage, pressure, gas, temperature, line, tap and supplier recommendations. Kegs are pressurised vessels and must be handled according to the manufacturer’s instructions.