Dr. Breen's Private Reserve is a brand of chemically-altered canned water that is manufactured and bottled by the Universal Union as a secondary means of controlling the human populace.
In order to provide an effective way to covertly wipe the memories of the human population and thus reduce the will to resist their rule, the Combine began canning and chemically treating water for distribution to the the civil populace, naming the overall brand "Dr. Breen's Private Reserve" as an obvious nod to the overall Administrator of Earth.
The chemicals within it are unknown outside the factories that manufacture them, but the effects are obvious, are citizens will begin to forget long-term memories through continued usage. Unfortunately for the citizens, continued usage is unavoidable due to the fact that they are both issued in citizens' rations and are the only legal beverage available to lower-ranking members of the Combine hierarchy, including the human populace.
Dr. Breen's Private Reserve comes in three different varieties, which are issued to different individuals depending on their social status:
Breen's Water (Blue)- The standard variety of Dr. Breen's Private Reserve, it is the most heavily treated with memory-replacement chemicals and therefore has the most negative effects on the mind. It is issued in standard citizen rations and purchased from Private Reserve vending machines, and is the only variety of Breen's Water that standard citizens are permitted to drink.
Smooth Breen's Water (Red)- The variety of Private Reserve issued to the Civil Worker's Union and the Metropolitan Police Force, it contains far fewer memory-replacement chemicals than its standard blue counterpart, conveying a sense of trust by the Combine to those who are permitted to drink it.
Special Breen's Water (Yellow)- The rarest variety of Private Reserve, it is essentially canned fresh water and is completely free of memory-replacement chemicals. A such, it is issued only to the highest members of society, such as Administrators.