Pre-tax profits fell from £1.3m in 2008 to £0.8m in the year to 30 September 2009, according to latest accounts filed at Companies House.
The drop in profit was "mainly due to a decrease in the income from volume through the business and significant price pressure from our customers," the company's directors claimed.
Although volume of product sold had fallen, turnover during the year rose £6.2m to £73.6m. The company attributed the rise to inflation and a switch by customers to added-value products.
It also said the fact there were only 339 days in the 2008 accounting period had affected its figures.
The company expected turnover in 2009/2010 to remain flat or even marginally decrease due to predicted deflation in prices.