The effect of using nonchlorine products for cleaning and sanitising milking equipment on bacterial numbers and residues in milk

Seven milking machine cleaning procedures which differed in the working solution content of sodium hydroxide, presence of chlorine, temperature of water, and inclusion of acid and four antimicrobial products used as sanitisers in the premilking rinse water were evaluated. The cleaning system, which incorporated a high working solution of sodium hydroxide (2525ppm) used in cold water combined with a hot (70 degrees C) daily acid wash, had lower total bacterial counts (TBC) (1040 colony forming units (cfu)/mL) than the same detergent product without the addition of acid (1980cfu/mL) (P<0.05). Lower TBC were observed in milk and on equipment surfaces when a sanitiser was applied (P<0.01). Trichloromethane levels in milk were higher when chlorine was used as a sanitiser (P<0.01).