Monitoring the Hygiene of Raw Milk from Farms to Milk Retailers

Milk from dairy cattle is a good source of nutrients for humankind around the world. In Thailand, milk from dairy farms is generally transported to milk collection centre (MCC) and then transferred to milk processing plant. However, some milk from MCC is sold to local milk retailers. The quality of raw milk is very important for people's health. Therefore, the aim of this study was to monitor milk hygiene during transfer from dairy farms to the MCC and from bulk tank milk to milk retailers by counting the microorganisms in raw milk using standard plate count (SPC) method. Raw milk samples of 15 dairy farms in Maha Sarakham province were collected in summer (Mar-Jun), raining (July-Oct) and winter (Nov-Feb) seasons. After milking, raw milk was collected for SPC test. Additionally, the time for milk transportation, environmental and milk temperatures in milk bucket were also recorded. Those parameters were repeatedly recorded at MCC before being poured into the bulk tank. Cooled raw milk in the bulk tank was sampled before packed in 5 kg plastic bag and carried to 9 milk retailers in town. The results found that the average of time for milk transport from dairy farm to MCC was 76.29 min. Milk temperatures decreased from farm to MCC for all seasons. The SPC of milk at farm in summer (5.812 log10CFU) was higher than in raining (5.743 log10 CFU) and winter (5.713 log10 CFU) (P<0.05) seasons. The SPC from farm to MCC significantly increased (P<0.05) in all seasons. The average of time for milk transportation from MCC to milk retailers were 89.44, 178.00 and 156.11 min (P<0.05) in summer raining and winter, respectively. In conclusion, more attention should be paid to milk hygiene and temperature from milking in the farm through milk retailers, especially in the summer. The microorganism could grow rapidly during milk transportation from farm to MCC in raining season. Thus, cooling down the milk or rapid delivery of milk bucket to MCC should be considered seriously.