What is the term used for the bottom of the down tube in a keg?

The term used for the bottom of the down tube in a keg is "sump." In a keg, the sump refers to the area where any sediment or residual beer collects. This is an important feature because it helps to ensure that the beer drawn from the keg is clear and free from unwanted particles, which could impact both the taste and appearance of the beer served.

Understanding the function of a sump is vital for those involved in the serving and handling of draft beer, as it plays a role in maintaining the quality of the beer and minimizing waste. Proper keg maintenance, including awareness of the sump area, is essential for ensuring that kegs are emptied efficiently and that the beer served is of high quality.

The other terms such as "drain," "outlet," and "port" may refer to different components or functions within a keg or the dispensing system, but they do not specifically denote the bottom area where sediment accumulates like "sump" does.