Effect of Low-Temperature Cleaning on Microbiological Quality of Raw Milk and Cleanliness of Milking Equipment on the Farm

Abstract
Milking equipment on four farms each in the St. Paul. Minnesota area and the Ithaca, New York area was cleaned at wash solution starting temperatures of 120, 130, 140, 150, and 160 F. The effect of wash solution temperature on raw milk microbiological quality was determined by the Standard Plate Count (SPC), Psychrotrophic Bacteria Count (PBC). Coliform Count (CC) and Laboratory Pasteurized Count (LPC). Cleanliness of the farm milking equipment was determined by microbiological counts (SPC, PBC, CC) of circulated sterile water, visual examination and determination of residual calcium on the equipment. Statistical analysis of the data indicated that Klenzade farm detergents and Agway farm detergents can be used at temperatures such that the final wash solution temperature does not drop below 105 F and have no significant effect on cleaning performance, microbiological quality of raw milk or microbiological status of the milking equipment.