Have You Checked Your Temperature Lately

A recent visit to try to resolve a fluctuating bacteria count showed a poor technique with no resolution.

Without optimal cleaning and disinfection protocols, the milking machine is one of the main vectors to spread mastitis and causing raised bacteria levels on a dairy farm.

With your thermometer, monitor the temperature of the rinse cycle at the return line.

Rinse water temperature below 93ºF (33°C) will allow milk fat to deposit on milking equipment surfaces.

Rinse water temperature above 120ºF (48°C) will denature any remaining protein and create protein films. These films are colourless at first but develop a yellow colour as they build up. Protein films provide contact areas on surfaces where bacteria can grow.

Most dairy farms use a chlorinated alkaline detergent in either liquid or powdered form. Add your detergent to the wash water according to manufacturer specifications.
At this point the client was using excessive amounts of detergent, causing only frustration.
Increasing the amount over and above the recommended rate is pointless.

Why chlorinated? The chlorine increases the solubility of any remaining protein and helps to remove it with the detergent wash water during the wash cycle

The temperature of the chlorinated alkaline detergent solution should be between 160ºF and 170ºF (71° – 82 °C) at the start of the wash cycle. Typically, the wash cycle is at least 10 minutes, but this will vary with each parlour depending on size and type of parlour

It is important the temperature of the chlorinated alkaline detergent wash does not fall below 120ºF(48C) as it leaves the system (check this with your thermometer), because any milk solids either in solution or in suspension may be re-deposited on contact surfaces.
The Clients thermometer was reading 140ºF (60C) however the actual reading was 120ºF (48°C)
On the first pass the temperature had dropped 30ºF (1.1°C)

In all cases, hot water volumes need to be sufficient to allow wash cycles to run at least 10 minutes above 120°F (48°C) if this standard can’t be met, hot water storage volumes must be increased.
A new water heater was fitted and the first month bacteria count had a huge drop and had stabilised.