By Laura McGuire Higher porridge and Rubicon sales helped AG Barr record a 25.9 per cent jump in revenue last year to £400m. The company, which is best known for making Irn Bru, reported profit growth of 15 per cent off the back of these numbers. Profit before tax hit £51.3m. As a result, the board has hiked its dividend by over 14 per cent to 15.0p. The drinks maker said its Rubicon brand had an excellent year, with sales up 15 per cent, driven by growth across the full brand portfolio. “Rubicon’s exotic fruit proposition and its vibrant and energetic brand positioning are proving a winning c…