Adds statement on investigation by the Department for Environment Health.

Tests at Malta Dairy Products have established that there was nothing wrong in a production batch which left the dairy on Friday and which has been the source of complaints by several people.

MDP company secretary Martin Grech confirmed to timesofmalta.com that a good number of people from all over Malta had complained that milk which had today's expiry date had gone sour early.

"We have carried out tests on samples of that batch kept in our laboratories and everything was in order. Further tests were carried out by the health authorities and they also found that everything was in order," Mr Grech said.

He could not explain what happened, adding that current high temperatures and a power cut on Sunday may have contributed. However, the problem did not appear to stem from the transportation of the product.

Mr Grech said that people returning their milk cartons to the dairy were having it replaced.

Meanwhile the Department for Environmental Health in a statement this afternoon said it is investigating a number of complaints with respect to the quality of Malta Dairy Products (MDP) milk.

The Department said it was too early to issue any result with respect to samples of milk elevated this morning.