Hanna, who has been chairman for five years and on the board for 11 years, told shareholders of his plans to retire at AG Barr’s annual general meeting yesterday.
Non-executive director John Nicolson has become deputy chairman and will replace Hanna as chairman when he leaves at the end of December.
News of his departure came as the Scottish drinks company reported that total sales increased by 5.2 per cent in the 15 weeks to 11 May compared with the same time last year.
The performance was a slight slowdown on the six per cent growth in first seven weeks of the year but ahead of the overall market, which according to Nielson grew in value by 1.9 per cent in the same period.
Chief executive Roger White said increased spending on marketing and advertisements ahead of the Glasgow Commonwealth Games had helped to boost its core brands.
The company, which also makes Rubicon and Orangina, said that while the economy had improved, the retail environment remained as competitive as ever. It said margins were in line with its expectations and remained confident on its full-year targets.