Adding vitamin E to irradiated meat could help reduce unpleasant odours and colours that put consumers off, according to a study presented at the American Chemical Society's annual conference held this week in Boston, USA.
Irradiating meat to prolong its shelf life can change its colour and smell in an unappetising way that the food industry is keen to correct, said Dong Ahn, a chemist at the University of Iowa. Many irradiated meats give off a sweet smell, he added.
"The first thing people look at is the freshness date, but colour and odour are very important in people choosing their meat products," Ahn said.
According to Ahn the look and smell is a major reason why less than 1 per cent of all meat sold in the US is irradiated. The US Department of Agriculture approved irradiating poultry in 1992 and red meat in 2000. Food irradiation is still unapproved in the European Union.
Exposing raw and refrigerated meats to radiation can kill bacteria and delay its spoilage by up to five days, Ahn said. The smell and colour changes occur when radiation causes oxidation.
Ahn was able to reduce changes in colour and smell by adding antioxidants, such as vitamin E and the sesame oil derivative sesamol, and double-packaging the food to reduce its exposure to air. These additives would have to be approved by the USDA and the US Food and Drug Administration before they could be sold.
Radiation kills bacteria such as E. coli, salmonella and listeriosis, all of which are potentially lethal meat contaminants.