Effects of different heat treatments on the bioactive components, bactericidal and antioxidative capacity of bovine milk

This study investigated the changes in native microbiota, representative bioactive components and functions therefrom of raw milk after heating for 15 s at different temperatures (from 72 to 100 degrees C). When a common high-temperature short time (HTST) pasteurisation (72 degrees C for 15 s) was applied, the total bacterial count was reduced by similar to log 2 cfu/mL relative to the raw milk; the retention of native lactoferrin, IgG, vitamin C and vitamin B-2 in milk was 73.1% and 77.8%, 80.8%, and 97.8%, respectively. As the heating temperature increased, the bacteriostatic and antioxidative capacity of milk decreased with the increasing loss of bioactive components. Furosine level was significantly increased when heating above 90 degrees C, whereas only after heating at 100 degrees C, a limited lactosylation of both alpha-lactalbumin and beta-lactoglobulin was found. This study provided an evaluation on the milk quality after HTST processing, providing a guidance for optimising dairy processing parameters.