Cooling, storing and quality of raw milk

Full-scale experiments with cooling of raw milk of good initial quality from a herd of 70 dairy cows have been performed under practical farm conditions, with different cooling and storage conditions, including instant cooling in a continuous process versus normal cooling in a batch process. During each milking, the milk was divided equally and successively for different cooling procedures. Quality evaluations (number of bacteria, acidity and oxidation of fat, sensoric quality) indicated that instant cooling/continuous process compared with normal cooling/batch process over 2.5 hours, both to 4 degrees C, resulted in a slightly slower bacterial growth and a slightly slower hydrolysis and oxidation of milk fat. Instant raw milk cooled and stored at 2.5 degrees C maintained a good quality for about one to two days more than when normal cooling over 1.5 hours and storing at 4 degrees C was used.