A consignment of soy milk found contaminated and destroyed in Japan must have been tainted en route, Vietnamese exporter Vinasoy has said.
Tests by the National Institute For Food Control on Monday did not find coliform bacteria in the Fami Calcium Soy Milk samples it had retained from the export consignment, it said.
But 640 packs imported to Japan by Next Trading company were found to have coliform and ordered to be recalled and destroyed in Chiba city.
A Vinasoy spokesperson said the contamination must have happened during the shipment or distribution process in Japan.
The spokesperson said that Coliform cannot survive the enzyme inactivation processes in which soy milk is heated to 120 degrees Celsius (248 Fahrenheit) and ultra-high-temperature sterilization at 140 degrees Celsius.
A carton of soy milk with coliform would be bloated and go sour in two to four days, and so the factory would have noticed any contamination right away, the spokesperson added.
Japan’s Ministry of Health, Labor and Welfare confirmed the contamination.
But a spokesperson for Next Trading told broadcaster NHK that while the company was “surprised and sorry” to learn about the contamination, it had tested the products based on health ministry standards before distribution and had not detected any coliform.
Since the news broke, Vinasoy has consistently said its product was not contaminated.
It has 25 years’ experience in making soy products and is the industry leader in Vietnam.
It exports to several other markets with high standards such as the U.S. and South Korea.
Coliform, which can be found in water and the feces of warm-blooded animals, does not often cause serious illness, but a person exposed to it could have an upset stomach, vomiting, fever, and diarrhea.