Results are expected today into whether milk products from a Southland dairy factory are contaminated by E.coli bacteria.
But the owner of the Happy Valley Dairy's factory at Tuatapere said the original sample must have been faulty as other samples tested had been fine.
Food safety officials yesterdaywarned people not to consume Happy Valley milk produced after October 14, because it may contain high levels of the bacteria.
Happy Valley sells its milk to supermarkets, dairies and other shops in the southern South Island.
New Zealand Food Safety Authority yesterday issued Happy Valley Dairies with a direction to recall milk produced on or after October 15.
The authority's compliance and investigation director Geoff Allen said all dairy factories were required to take random microbiological samples of their product and the sample was found to contain high levels of E.coli.
While the cause of the contamination was yet to be established, it was likely pasteurised milk had come into contact with faecal matter, possibly in raw milk or through "some other mechanism" he told The Southland Times.
E.coli could cause serious illnesses, including gastroenteritis, and people with concerns should seek medical advice.
Happy Valley Dairy owner Frans Venekamp said his feeling was the problem had arisen from a sample being too warm as it was tested, because cream produced from the same milk had tested fine.
Further testing was being carried out on milk produced on October 16 and 17 and if those tests showed there was a problem, the company would take steps to fix it, he said.
Results from those tests were expected today, he said.
