Ten minutes before you arrive at the Havana Club bottling plant, the sweet smell of molasses already permeates the salty Atlantic air. The smell becomes even stronger as you turn off the old Havana-Matanzas highway and enter the plant's grounds.

Also obvious on closer inspection are broken windows, peeling paint and a general air of neglect that make this rum distillery, said to be the world's largest, appear decades older than its 13 years.Despite the decay, Havana Club's owner, the Communist government of Fidel Castro, is pressing the plant's 860 workers to boost rum exports and pump

dollars into an economy that seems closer to collapse than at any time since the revolutionary leader's rise to power in 1959.

Ruben Rubi Armenteros, head of sales and production for Combinado de Bebidas Santa Cruz, which operates the factory, said production last year totaled 16 million liters (4.2 million gallons), of which 8 million liters were bottled rum and 8 million liters were bulk rum. This year's projections call for a total of 20 million liters, with 10 million liters in each category.

"Although we supply our national rum industry, our principal objective is to export," Mr. Rubi told The Journal of Commerce during an interview that was also attended by the company's protocol officer and the local Communist Party chief.

"About 25 percent goes for local consumption, and 75 percent for export," Mr. Rubi said. "This year, the Soviet Union will buy half of our rum exports."

Other principal markets for Havana Club include West Germany, East Germany, Spain, Italy, France, Canada and Mexico, he said. Because of Washington's 29-year-old trade embargo against Cuba, no Cuban rum - Havana Club or otherwise - may be sold to the United States, even though the Florida Keys lie just 90 miles from Cuban shores.

According to official government statistics, Cuba's total rum output totaled 49.96 million liters in 1988, up from 13.79 million liters in 1970. Cubaexport, the state agency that handles marketing and promotion of the country's chief exports, declined to divulge rum sales, dollar amounts spent on advertising or even estimates of how many Cubans work in the industry.

Mr. Rubi said the Havana Club factory in Santa Cruz is one of only five large rum distilleries and numerous smaller ones scattered across the island.

"All of these are insufficient to supply the national demand, since Cubans love to drink rum," Mr. Rubi said.

Yet one Havana-based foreign observer who asked not to be named said, ''Cuban rum is almost impossible to sell in the free market because Puerto Rico's Bacardi has monopolized that market. Rum was a good bet to sell in the U.S.S.R and Eastern Europe and was cheap to produce, though the quality of Cuban rum started falling six to eight years ago."

Mr. Rubi disputes that, insisting, "Havana Club has six medals attesting to the quality of our rum, including the Marca Estatal de Calidad." If anything, he said, the Communist revolution has put Cuba on the world map as far as quality rum is concerned.

"This factory was founded in 1919, and in the beginning was dedicated to alcohol and aguardiente (spirits)," he said. "During World War II, it was very difficult to produce because of fuel shortages, and by 1959 the factory was practically obsolete.

"In 1960, the plant was nationalized and passed to the people's hands. Production was at a minimum level. In the first years of the revolution, the workers revitalized the factory and increased production to 100,000 liters a day, compared with between 28,000 and 30,000 liters before the revolution."

In April 1976, construction of a new, 995,000-square-meter factory began at the old bottling site. Fidel Castro himself dedicated the plant in September 1977, and it reached full production in 1983.

Using an average figure of 40-proof, total aging capacity at the plant works out to 30 million liters. Each of the plant's warehouses contains 2,800 oak barrels, each of which holds 200 liters. Bulk rum is aged in 500-liter containers and exported to other rum producers throughout the Caribbean and Latin America.

Mr. Rubi said the final product is loaded onto 40-foot Soviet railway containers for transport to Matanzas harbor, where Morflot, the Soviet merchant shipping line, ships the rum to Europe.

"We produce four types of Havana Club: three-year rum, five-year rum, Exquisite - distilled from cane juice - and Silver Dry, a mixer," he said. ''This year, we'll begin producing a seven-year rum." Mr. Rubi added that Havana Club doesn't use chemicals or coloring as does Bacardi, "which has to use chemicals to maintain its high levels of production."

Unlike Puerto Rico, however, where locals can pick up a case of Bacardi at any corner grocery, about the only places Havana Club can be found in Cuba are the diplotiendas (special stores for diplomats), hotels and the duty-free shop at Jose Marti International Airport, where a 750-milliliter (one-fifth of a gallon) bottle sells for between $4.20 and $4.80.

- Larry Luxner