MINAZ is the abbreviation of Ministerio de Azúcar; the Ministery of Sugar. Traditionally it is responsible for the mills and the export and distribution of the sugar products. Since 1981 both the agricultural and the industrial sector involved in the production of sugar fall under this ministery.
The ministry is of course situated in Havanna. MINAZ has several provincial offices, which report about the sugar mills in their region.
The sugar mills are called Centrals in Spanish, or officially Complejo Agro Industrial. Anyway this is always abbreviated to "CAI".
After the revolution the sugar mills all received a 3-digit number. The mills are numbered from west to east, starting with CAI 102 and ending at CAI 641. As there were only about 155 mills, not all numbers are used.
The first digit of a mill number refers to one of the then 6 provinces it was situated in. See the map for the provincial borders from 1959. Later the provinces have been restructured but the millnumbers have not been changed accordingly. This makes the numbering scheme a bit confusing at present.
A map of Cuba with the 1959 provincial borders and the CAI-numbers.
The mills are mainly named after persons who have played an important role in the communist revolution in Cuba. Especially many members of Fidel Castro's "26th of July" group have a mill named after them. Some mills are named after important historic dates, again mainly dates marking important events during the Fidel's communist uprising in Cuba. It should be noted that the former privat-owned mills have often been renamed after Fidel kicked out the American sugar barons and nationalised the sugar industry. The full renaming scheme can be found on the CubaGenWeb.