Assessment of proteolysis in ultra-high temperature milk using attenuated total reflectance-Fourier transform infrared spectroscopy

This study investigated the suitability of attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) as an alternative technique to assess proteolysis in ultra-high temperature (UHT) milk. Commercial UHT milk samples were stored (5 and 30 degrees C) and analysed for four months. Milk samples were treated with acetic acid and trichloroacetic acid to obtain milk extracts containing peptides. The concentrated extracts were subjected to ATR-FTIR, and the spectrum was obtained. Results were compared with techniques like high-performance liquid chromatography, fluorescamine and 2,4,6-trinitrobenzenesulphonic acid. The present study indicated that ATR-FTIR-based method can be used as an alternative method for assessing proteolysis in UHT milk.