The team from NIZO said that oxidation of fatty ingredients, including well protected poly-unsaturated fatty acids, can now be determined. The Dutch scientists said they have developed a new method to extract all fats from foods such as infant formula, and as such are able to find a reliable peroxide value (POV) can be determined.
However, based on the knowledge of behaviour of proteins and fats in foods, the NIZO team have now developed a unique method that allows the full release and extraction of fats, even those embedded in the food matrix.
Kees Olieman, senior scientist at NIZO, has already applied this method in testing new ingredients: “Now we can help industry in reliably testing new emulsifying technologies or new fat-based ingredients.
“The good news,” he said, "is that it also helps companies to prevent discarding foods that in the past were rejected based on incomplete fat extraction.”
The researchers said that in order to get a reliable measure of the shelf life, all fats therefore need to be extracted. In this way the true peroxide value can be determined. However, they noted that specialty powders, such as infant formula, contain high levels valuable fatty acids that are prone to oxidation. As a result these compounds are encapsulated to protect them from deterioration and unpleasant off-tastes.
The current extraction methods “are no longer sufficient in the case of powders that contain fats with a protective layer,” said the researchers.
“At best partial extraction can be achieved and sometimes no fats can be extracted at all,” they noted.