Coffee retailer Starbucks Corp. (SBUX) now only serves Fairtrade certified coffee in its espresso-based beverages at stores in the U.K. and Ireland, the company announced Wednesday.

Starbucks is the world's largest buyer of Fairtrade coffee, and the switch to Fairtrade in the U.K. and Ireland will boost the incomes of farmers in Latin America, the origin of most of its Fairtrade coffee, the company said.

The move follows Cadbury PLC's (CBY) decision to make its dairy milk chocolate bars with Fairtrade certified cocoa and Tate & Lyle PLC's (TATYY) commitment to achieve Fairtrade certification on its retail sugar.

-Sarah McFarlane, Dow Jones Newswires; sarah.mcfarlane@dowjones.com