What's the deal with thermoduric bacteria?


The customer is always right and never more so than now for dairy. Competition for market share doesn’t just come from the dairy aisle but from the so-called alternatives  to milk and milk-based foods. So, as dairy companies strive to improve taste, eating quality and shelf life of their products, they are embracing technology to drill down into what really impacts the quality of the milk they process.



Moving from TBC (Total Bacterial Count) to Bactoscan saw a shift from measuring only the bacteria which formed colonies when grown in culture to a more sophisticated, and significantly quicker, measure of all bacteria in the milk. This allowed us to understand more about the total amount of bacteria in milk but not which types of bacteria were present. The development of a measure of thermoduric bacteria – heat resistant bacteria – has allowed processors to identify where milk contains bacteria which survive the pasteurisation process so can impact shelf-life and taste of the end products, and in extreme cases health of the consumer even after processing.

Now, a number of milk processors, and retailers, have moved to start to measure these bacteria and act on the level within milk in the same way as they would Bactoscan or somatic cell count.

But what are thermoduric bacteria and how do you control them on farm? As noted, thermoduric bacteria are a group of organisms that can survive high temperatures whether in processing or on farm in the cleaning process and spore forming (and pathogenic) bacteria such as Bacillus and Clostridium are commonly implicated in high thermoduric counts.

Thermoduric bacteria are prevalent in the cow’s environment accumulating in silage, slurry, soil and bedding. Housed cows are typically seen as being more at risk but soil contamination from cows at grass should not be overlooked. The bacteria find their way onto cow’s teats before being transferred onto the milking equipment and then into raw milk meaning that pre-milking routine is more important than plant cleaning  in controlling the presence of these bacteria.

As the main, initial cause of contamination comes directly from teat surfaces, care should be taken to keep cow housing as clean as practically possible and to adopt some form of thorough teat disinfection routine in the parlour, prior to cluster application. Lack of good teat hygiene at this stage is the primary reason that milk supplies can become contaminated with spore-forming bacteria.


Once these bacteria find their way into the milking equipment they can create a biofilm where micro-organisms stick to each other and then onto surfaces, creating a residue which is invisible and often difficult to remove.


Implementation of a pre-milking routine is paramount to ensure teats are clean and dry before cluster attachment.  The benefits are multiple as not only will the right pre-milking routine lead to improved hygiene, but also quicker milk let down, increased yield, improved teat health and reduced milking time as shown by many studies.



Pre-milking products range from sprays, to dips to foams so how do you know what is best? Using a product which has a fast and efficient kill time, lifts and removes dirt from the skin and works even in the presence of milk (for those cows with natural rapid let down mechanism) should be the aim. PreGold from the UdderGold range meets all of these requirements.

As a foaming product it works via immersion of the teat and uses up to 50% less product than a dip and 75% less than a spray making it economical as well as efficient – studies have also shown foams to be 50% more effective than a dip. The unique mode of action of PreGold with its micro-bubbling action means that the active ingredient (chlorine dioxide) has an explosive release lifting dirt from the teat surface which also helps leave the teat dry post-wiping, again reducing the ability of any external dirt travelling toward the teat opening during milking.




Combining a unique mode of action with a quick (under 20 seconds) kill time across a broad range of bacteria, viruses and other pathogens ensures more thermoduric bacteria are removed from cows’ teats pre-milking. This reduces contamination of milk and the milking plant at the initial steps (see sidebar for more steps on thermoduric bacteria control strategies).

Thorough, and effective plant and bulk tank cleaning supports the control of thermoduric bacteria in milk but prevention of bacteria entering the cluster, and subsequently the bulk milk supply, is key to controlling thermoduric counts. Addressing cow environment, cow cleanliness and teat (and udder) hygiene are primary to addressing the challenge and ensuring your pre-milking routine maximises both cleaning and stimulation will give multiple, tangible benefits.


For more information on our products or to find a local stockist please contact us.