A sale of Chi, part of the unlisted conglomerate TGI Group, would be the latest investment opportunity in Africa's burgeoning food and drink sector for multi-nationals seeking to cash in on the continent's emerging middle class.

The Lagos-based maker of juices and nectars, milk and yogurt drinks and snack foods is being advised by Citigroup, said the sources, who declined to be identified as the matter is private.

Chi had earlier hired Goldman Sachs to advise it on strategic options in 2012, the sources said.

The company, which could not immediately be reached for comment, has several hundred million dollars in revenue, according to one source. It could be valued at as much as $1 billion, said another source.

A decision is expected later this year on whether Chi's owners will pursue an initial public offering or a sale, said one of the sources.

Chi could be attractive to multi-national drink makers such as Coca-Cola (>> The Coca-Cola Company), PepsiCo (>> PepsiCo, Inc.), Danone (>> DANONE) and Suntory Beverage & Food (>> Suntory Beverage & Food Ltd), as well as private equity firms, the sources said.

Earlier on Friday, French dairy giant Danone said it was buying a 40 percent stake in Brookside, East Africa's top dairy producer for an undisclosed price. Last year, Danone bought 49 percent of a West African maker of frozen dairy products and juices, and also took control of Morocco's top dairy company.

Chi's owner, TGI Group, is an international investment and holding company with diversified interests in a range of emerging markets and industries from poultry and fish farming to frozen foods and juices to oil field services.

Goldman Sachs declined to comment. Citi was not immediately available.

(Editing by David Clarke)

By Martinne Geller and Anjuli Davies