Determination of ultra-low milk fat content using dual-wavelength ultraviolet spectroscopy

A precise determination of milk fat content in dairy products is of great practical importance. Several studies have reported methods to determine the milk fat content in commercial dairy products. However, very few of them validated or tested cases where the fat milk fat content was ultra-low. Here we present an approach to determine ultra-low milk fat content. This method involves extracting milk fat using n-heptane and determining its content using dual-wavelength UV spectroscopy. The results showed that milk fat at ultra-low concentrations (i.e., as low as 0.148 g/L) could be extracted completely and quantified accurately using the proposed approach. This method is reproducible and sufficiently precise. We expect that this method can be adapted by industries to determine ultra-low concentration of fat in milk and other dairy products with confidence.