Relationships between the variability of the global quality of cow's milk in Morocco and milking conditions

摘要

The evaluation of the quality of bulk milk obtained from 76 dairy farms in Morocco has shown a great variability of its physical (pH and density) and chemical (fat content, proteins and urea) parameters. In numerous cases, the value of these parameters has revealed poor rearing practices and even frauds (watering, skimming). The evaluation has also indicated that milk hygienic criteria used in this study (aerobic plate count, total and faecal coliforms) were even variable. A follow-up study of farmsand their housing conditions has allowed differentiating four types of milking conditions: "mechanical and clean", "manual and clean", "manual and relatively clean", and "manual and dirty". These different types of practices were found to have an impacton the hygienic quality of milk, particularly on the fecal coliforms count, which increased significantly from " mechanical and clean' to "manual and dirty " milking conditions. These results suggest a closer monitoring of the milking conditions as meansof classifying milks and the interest of using milk pH, as an easy and cheap indicator of the milk hygienic quality because of its high correlation with the hygienic criteria.