IMPROVED SHELF LIFE ESTIMATION OF UHT MILK BY PREDICTION OF PROTEOLYSIS

During growth in raw milk, many psychrotrophic bacteria produce proteases that can retain activity following ultra-high temperature (UHT) treatment. In this study, casein and skim milk powder assays for detecting very low levels of protease in UHT milk were optimized, and the suitability of azocasein and fluorescein isothiocyanate-casein (FITC-casein) as substrates was investigated. The strongest correlations of protease activity with...