Warburtons has reported a 52% increase in operating profit after diversifying and expanding its range.

The family-owned north-west bakery saw its turnover rise by 7.3% to £562.1m in the year to 28 September 2013.

While faced with an 8.5% rise in the cost of raw materials - resulting from a jump in the price of wheat - the company still saw profits increase to £33.9m.

The Bolton-based company attributes this success to the introduction of sandwich alternatives, such as wraps and sandwich thins, which have provided the biggest line of growth.

In the directors’ report, chairman Jonathan Warburton said: “The Warburtons business has continued to focus on the quality of product and service in order to maintain differentiation in what continues to be a very competitive market.

“Investment is focused on enhancing our capability to meet changing consumer trends. This focus on meeting customer needs continues, in order to ensure we are well-placed to progress in the future.”

“We will remain committed to growth and diversification and continue to invest in our people, innovation and infrastructure, as well as in new growth areas, such as our free-from business.”

The company, owned by the fifth generation of the family, has 12 bakeries across the country and, in March, was granted permission for a £20m revamp of its Burnley site, which will make wraps and sandwich thins.