Shares in Northern Foods have dropped by 18% after the firm issued its second profit warning in two months.
The Leeds-based firm said sales in the past two months had been "very disappointing", with biscuit sales down 12% in January and February.
Sales of pastry products fell 11%, which the company attributed to healthier eating trends.
Northern Foods said it expected annual profits to be in the region of £45m ($77m), down from £62.2m last year.
The company - which employs about 20,000 people in the UK and the Republic of Ireland - makes own-label products for food retailers, and also produces branded foods such as Fox's Biscuits, Goodfella's pizza and Pork Farms pies.
Underlying sales for the first two months of the fourth quarter were unchanged on a year ago, the company said.
While biscuit, pastry and chilled food sales were disappointing, Northern said that its frozen food division had "continued to perform well".
Northern said that it was currently carrying out a strategic review to examine its "business model, product portfolio and cost base" with the results of the review expected to be reported on 31 May.
Shares in Northern Foods ended the session 22.25 pence, or 17.12%, lower at 107.75p.