| Abstrakt: |
In order to determine a suitable temperature and time combination for the proper pasteurization of milk under conditions in Cameroon, the destructive effects of heat on the peroxidase and micro-organisms in local milk were studied. In the first step, fresh milk samples were heated at temperatures of 64–100°C for 1 min. Peroxidase was found to be sensitive to heat treatment at temperatures of 74–76°C and completely destroyed above 78°C. In the second step, fresh milk samples were heated to 74°C and held at that temperature for 15 s, 5 min, 10 min, 15 min or 20 min; microbiological analyses revealed that survival rates were 56.7, 1.5, 0.2, 0.06 and 0.05%, respectively. Peroxidase was completely destroyed after 10 min at this temperature. In terms of microbial quality, there were no significant differences (P < 0.001) between holding times of 10, 15 and 20 min. A heat treatment of 74°C for 10 min yielded milk free of peroxidase and with < 10 000 cfu/mL. It is recommended that raw milk be given at least this treatment to ensure safe milk supplies in Cameroon. [ABSTRACT FROM AUTHOR] |
