Dairy Crest said the sale of own label juice operations at Kidlington, Oxfordshire, would incur a one-off charge of £3m.
For the six months ended September, Dairy Crest said its Clover and Utterly Butterly brands had combined volume growth of over 10%. And that St Ivel Gold would be relaunched in October with a new TV commercial.
Cathedral City cheese, Frijj milk drinks and Yoplait yogurt had "performed strongly with double-digit volume growth and increased market share".
The dairy group said consumer demand for mature cheddar had helped reduced excess stock and seen prices rise.
Interim results will be announced on November 12.