All beers are at their best on the day the keg is filled at the brewery. As days go past the freshness reduces. In general, the fresher your keg draft beer is, the better it tastes. Keg beer will remain fresh if dispensing with CO2, while maintaining the proper temperature and pressure: For non-pasteurized draft beer about 45-60 days. For pasteurized draft beer about 90-120 days.
When dispensing keg beer with a party pump (air), any draft beer will remain fresh for no more than 8-12 hours
For quality assurance, most breweries now print a freshness date on the cap or side of each keg. Depending on the brewery, this may either be a “born on” (filled) date or an “expiration” date, read the label carefully. While the shelf life for each of the brewers may differ, days in inventory before it reaches you are factored into the shelf life of the keg.
For example Non-pasteurized beer has a shelf life of 45-60 days. Here is an example of a keg’s life:
- Days 0-10 (Transit / Satellite Warehousing)
- Days 10-20 (Distributor Warehouse / Retail Delivery)
- Days 20-60 (At Retail / Home)
So the average keg has 25-40 days of shelf life at retail or in a home. Breweries recommend not drinking draft beer past the freshness date. Don't forget that air contains oxygen, and oxygen is an enemy of beer!