It said ingredient costs would rise after the price of wheat hit a 22-month high last week, with wildfires destroying crops.
But pre-tax profit for the half-year was £18.6m – up 12.3 per cent on the same period last year.
Revenue rose from £312m to £321m.
The company said that despite the setback triggered by wheat prices the company would make progress.
Chief executive, Ken McMeikan said: "We have delivered a resilient first half performance under challenging conditions."