Turnover increased to £327.6m compared to £291.9m in the same period 2006, the company reported yesterday in an interim financial statement.
Sales volumes rose by 5.2 per cent to 745.6m litres in the six months to 29 September.
Operating profit rose by 10.4 per cent to £19.3m compared to the same period in 2006.
Operating margin was 5.88 per cent, compared to 5.72 per cent during the same period last year.
Robert Wiseman, the company's chief executive, said a new processing plant in Bridgwater will begin production next month, allowing the company to meet the rising demand.
"The slow but steady recovery in margins enjoyed over the last few years is due to the improved efficiencies within our supply chain," said Wiseman.
"This has undoubtedly been assisted by the stability in contracts with our multiple retailer customers."
The company cited as operational highlights during the year the start in July of a contract with Sainsbury to own label organic products.
The company has also established dedicated supply groups for Tesco and Sainsbury.
To secure its raw milk supply Wiseman increased by 37 per cent, or 7 pence per litre since February.
A new milk haulage depot opened in Market Drayton is delivering further efficiencies, the company said.
The company also noted the benefit of the increased contract with the Co-operative Retail Trading Group from July 2007.
In March 2007 the company began supplying Booths for the first time.
Another advance was made by segregating a milk supply group just for Tesco's own label products.
Tesco pays a premium price to dairy farmers in the group.
The company also reported the strengthening of its position in the organic market.
In addition to a packing arrangement for the Rachel's organic brand with Horizon Organic Dairy, the company has started supplying Sainsbury's own label organic dairy products from 1 July.
Wiseman's started supplying organic dairy products to Tesco from November 2006.
The company reported that it now supply these major customers with organic volumes in line with its share of their own label milk.
The company's brands continue to show good growth.
Sales of 'The One' rose 37.5 per cent in the six month period compared to last year.
Sales of 'Pure', Tesco's own brand of extended shelf life milk, and 'Puriti', Wiseman's own brand, recorded a sales growth of 30.3 per cent on the same period last year.
"The focus of attention at our dairies has been keeping up with record demand from our customers," Wiseman reported.
The Bridgwater dairy remains on target to achieve production prior to Christmas in a phased start up.
The new £75m dairy will reach its initial capacity in late spring 2008, Wiseman's stated.
"This new dairy will set the standard for the rest of the industry in terms of efficiency, both operationally and environmentally, and will also allow our two major English dairies to cease seven day working and return to a more cost effective pattern of production," the company stated.
"We will also see a significant reduction in trunking costs as we cease shipping milk to and from the south west of England."
On the horizon, Wiseman faces an investigation by the Office of Fair Trading into price fixing among dairy companies supplying fresh process milk to retailers in Scotland.
The company has disputed the findings and is awaiting a response from the OFT.